bluuebunny/crossref_metadata_2025 huggingface dataset:
Administrasi Kurikulum
Authors: Putri Novia Elmoza , Afriansyah Hade , Hadiyanto Hadiyanto
Published: May 2019

This article explain about curriculum administration, where curriculum administration is a collection of teaching materials that serve as guidelines for educators in the learning process. The administration of this curriculum aims to assist education implementers from planning dan implementing. Administration of this curriculum is made on the agreement of the parties concerned to achieve national education goals. This article is written using a literature study technique, where the author collect material or data sourced from books journals and other sources related to curriculum administration.
KELOMPOK 8
Authors: HAKIM NANDA DIAN , hidayat  , manalu afrida
Published: May 2019

PKn adalah untuk membentuk watak atau karakteristik warga negara yang baik.Karakteristik PKn sebagai pendidikan konsep, nilai, moral, dan norma dalam pembelajaran PKn.
An introduction to the bootstrap: a versatile method to make inferences by using data-driven simulations
Authors: Rousselet Guillaume A , Pernet Cyril R , Wilcox Rand R.
Published: May 2019

The bootstrap is a versatile technique that relies on data-driven simulations to make statistical inferences. When combined with robust estimators, the bootstrap can afford much more powerful and flexible inferences than is possible with standard approaches such as t-tests on means. In this tutorial, we use detailed illustrations of bootstrap simulations to give readers an intuition of what the bootstrap does and how it can be applied to solve many practical problems, such as building confidence intervals for many aspects of the data. In particular, we illustrate how to build confidence intervals for measures of location, including measures of central tendency, in the one-sample case, for two independent and two dependent groups. We also demonstrate how to compare correlation coefficients using the bootstrap and to perform simulations to determine if the bootstrap is fit for purpose for a particular application. Our approach is to suggest and motivate what could be done in a situation, with an understanding that various options are valid, though they may help answer different questions about a dataset. The tutorial also addresses two widespread misconceptions about the bootstrap: that it makes no assumptions about the data, and that it leads to robust inferences on its own. The tutorial focuses on detailed graphical descriptions, with data and code available online to reproduce the figures and analyses in the article (OSF: https://osf.io/8b4t5/; GitHub: https://github.com/GRousselet/bootstrap).
Manuscript Family Connectedness and Self-Control
Authors: Willems Yayouk , Laceulle Odilia , Bartels Meike , Finkenauer Catrin
Published: May 2019

Objective: Family connectedness is key for the development of self-control in early and middle childhood. But is family connectedness still important during the transitional phase of adolescence, when adolescents demand more independence from their parents and rely more on their peers? The aim of the present study was to investigate the association between family connectedness and self-control, and whether it still holds in adolescence using a genetically sensitive design. Method: Data were used from a large sample of twins aged 14 (N=11,260) and aged 16 (N=8,175), all enrolled in the Netherlands Twin Register. We applied bivariate twin models and monozygotic twin difference models to investigate the association between family connectedness and self-control and to unravel to what extent genetic and environmental factors explain this association. Results: The results showed that more family connectedness is significantly related to better self-control in adolescence, albeit with a small effect size. Twin analyses revealed that this association was mainly explained by common genetic factors and that the effects of environmental factors were small.Conclusions: The current findings confirm the role of family connectedness in adolescent self-control. Importantly however, the results demonstrate that phenomena we see within families seem the product of parent and children sharing the same genes rather than being exclusively attributable to environmental processes.
Applying Crossref and Unpaywall information to identify gold, hidden gold, hybrid and delayed Open Access publications in the KB publication corpus
Authors: Akbaritabar Aliakbar , Stahlschmidt Stephan
Published: May 2019

Identifying Open Access (OA) publications might seem a trivial task while practical efforts prove otherwise. In this project, we wanted to assign OA tags to publications in KB database. We queried KB in-house database up to 2017 (including Web of Science (WOS) and Scopus) for all articles and reviews. We then matched the corresponding DOIs to three sources of OA information: Unpaywall, Crossref and Bielefeld list of gold OA journals. This allowed us to define the OA status for publications. We found close to 14 million publications (articles and reviews between 2000 and 2016) from WOS (69.75% of all) and close to 18 million from Scopus (68.67% of all) with an equivalent DOI in Unpaywall. We matched KB publications database with Crossref data (from April 2018) and found 53 distinct licence URLs, which define in many cases the legally binding access status of publications. We found that more than half a million publications have more than one licence record in Crossref (in contrast to near 8 million with only one record and more than 6 million without a licence URL). We evaluated if these licences were open or closed access. We also matched respective journal ISSNs with DOAJ and ROAD databases and presented a categorization of publications to Gold, Hidden Gold, Hybrid and Delayed OA accounting for uncertainty due to missing licence information via a new sub-category Probable Hybrid OA. We validate our findings via manual checks and a crosscheck of OA information from the aforementioned varying sources. While the manual check on a sample of publications revealed a small but noticeable degree of apparently incorrect meta-information on publication’s OA status, the contrast of OA information from the diverse OA information sources highlights the partially unsteady base for an OA monitoring based on open data.
Electrical Energy Steam Boiler Heat Loss Analysis in Japfa Comfeed Indonesia Tbk, Unit of Sidoarjo
Authors: Priyandana Joseph , Jamaaluddin Jamaaluddin
Published: May 2019

In the animal feed industry, steam is used in pellet making machines. In this process, steam from the boiler is distributed to the pellet mill through the pipe. The purpose of this study is to observe the waste of electricity costs of operating a boiler by calculating heat loss in a distribution pipe. The method of assessing heat loss is done by calculating losses caused by heat loss in the boiler distribution. Then make a calculation application model based on the data obtained. From the data analyzed, the amount of heat lost in the non-insulating distribution pipe is 0.766 kJ/s with a loss of Rp 5.628,600 operating costs per month compared to heat loss in an isolated pipe condition of 0.047 kJ/s with losses which cost slightly more than Rp 368 190 / month. This heat loss calculation process is made on an android application by entering the calculation formula on the program and the data that has been obtained.
PELAKSANAAN TANGGUNG JAWAB SOSIAL PERUSAHAAN (Corporate Social Responsibility) SEBAGAI SALAH SATU INSTRUMEN DALAM PEMBANGUNAN DAERAH
Authors: Azheri Busyra
Published: May 2019

Given the limited funds of regional development, it is expected that CSR activities can be usedas an instrument in the regional development. This requires commitment from both parties forcorporate and government to formulate a clear policy, in accordance with the competenciesthey possess. So that CSR is not only beneficial to the corporation but also felt by the peopleand government in regional development.
SEBUAH WACANA HAM TENTANG “HAK ATAS KEPEMILIKAN”
Authors: Kurniawan Nalom
Published: May 2019

Among vatious rights in the human rights discourse. The right of ownership is one of the rightswhich is interesting to discuss. It is because regulations of rights of ownership is not stated inthe derivation of the UDHCR (ICCPR/ICESCR) covenant. Moreover, various concepts andviews on the rights of ownership have different characteristics and uniqueness. Protection ofthe right of ownership may conflict with other rights (public interest).
Lipid Profile in New and Recurrent Ischemic Stroke Patients at Haji General Hospital of North Sumatra Indonesia
Authors: Andina Meizly , Pratiwi Lisa Nabila , Aribowo Fadhilah Ramadhan
Published: May 2019

Introduction: Stroke refers to any sudden neurological disorder that occurs due to the cessation of blood flow through the arterial supply system of the brain. The etiology obstructions are atherosclerosis. There was an imbalance of lipid profiles in patients with ischemic stroke There was an imbalance of lipid profiles in patients with ischemic stroke. The objective of this research is to determine differences between lipid profile in new ischemic stroke patients with recurrent stroke at Haji General Hospital of North Sumatra Indonesia in 2015-2016.Methods: This is a cross-sectional study using total sampling method with a total of 64samples. Secondary data obtained from General hospital Haji Medan. Secondary data collected were data on lipid profile in patients with acute stroke and recurrent stroke by collecting medical records.Results: The result from the acute stroke patients found HDL levels of 33.97 mg/dl, recurrent stroke patients found HDL levels of 35.25 mg/dl. LDL levels in acute stroke patients were 109.56 mg/dl and recurrent stroke patients were 123.16 mg/dl. In new ischemic stroke patient, the average value of triglyceride levels was 143 mg/dl and the average value of total cholesterol was 205.8 mg/ dl. In recurrent ischemic stroke patient, the average value of triglyceride levels was 165.2 mg/dl and the mean total cholesterol level was 180.8 mg/dl.Discussion: There are no differences of lipid profile in new and recurrent ischemic stroke patients at Haji General Hospital of North Sumatra Indonesia in 2015-2016 (p>0.05)International Journal of Human and Health Sciences Vol. 03 No. 03 July’19. Page: 146-149
Failure of Aircraft Engine Crankshaft
Authors: Craft C. Howard
Published: May 2019

A broken aircraft crankshaft and a severely damaged main brass bearing were examined to determine whether engine failure was initiated in the bearing or in the crankshaft. The steel crankshaft failure was a classical fatigue fracture. The bearing had been subjected to extremely high temperatures, as indicated by melting in the brass components and the extreme distortion in the rollers. Microscopic examination on the crankshaft material showed it to be a good quality steel. On the other hand, the chromium plate was thick, porous, and cracked in many places, including the point of the main fatigue crack. It was concluded that the over-all failure was initiated in the crankshaft, and the failure of the bearing resulted from that failure.
Dimpling of Aluminium Sheet
Authors: Wittig Ruth , Rickel Jürgen
Published: May 2019

Countersunk riveted joints in aluminum sheet are widely employed in the aircraft industry. The preparation of the sheet for the riveting process consists either of countersinking where the sheet is sufficiently thick or of dimpling. Metallographic assessment of dimple defects is described in specimens made of clad aluminum sheet of alloy type AlZnMgCu1.5. Addressed are a dimple with partially missing stamped surface (bell-mouth), a cylindrical prominence because the dimpling force was too great and the stamping cylinder force too low, and a dimple with flashes at the top surfaces of the sheet as a result of play between the stamping cylinder and the anvil head (ringed dimple). Frequently, overlapping of several defects occurs, especially with steel or titanium sheet, with the result that it is difficult to identify the defects.
Use of Electron Fractography to Diagnose Cracking in an AISI 4340 Nose Landing Gear Cylinder
Authors: Scott James A.
Published: May 2019

Examination of a cracked nose landing gear cylinder made of AISI 4340 Cr-Mo-Ni alloy steel proved that the part started to fail on the inside diam. When the nucleus of the stress-corrosion crack was studied in detail, iron oxide was found on the fracture surface. A 6500x micrograph revealed this area also displayed an intergranular texture. One of a group of small grinding cracks on the ID of the cylinder nucleated the failure. Other evidence indicated the cracks developed when the cylinder was ground during overhaul.
Failures in Airplane Engine Crankshafts
Authors: Shah Jivan B.
Published: May 2019

This report covers case histories of failures in fixed-wing light aeroplane and helicopter components. A crankshaft of AISI 4340 Ni-Cr-Mo alloy steel, heat treated and nitrided all over, failed in bending fatigue. The nitrided layer was ground too rapidly causing excessive heat generation which induced grinding cracks and grinding burn. Tensional stresses resulting from grinding developed in a thin surface layer. On another crankshaft, chromium plating introduced undesirable residual tensile stresses. Such plating is an unsatisfactory finish for crankshafts of aircraft engines. Aircraft engine manufacturers and aeronautical standards require magnetic particle inspection to detect grinding cracks after reconditioning. Renitriding after any grinding is needed also, regardless of the amount of undersize as it introduces beneficial residual compressive stresses.
Stress Corrosion Cracking of 4340 Steel in Aircraft Ignition Starter Residues
Authors: Kennelley Kevin J. , Daniels Raymond D.
Published: May 2019

Military aircraft use a cartridge ignition system for emergency engine starts. Analysis of premature failures of steel (AISI 4340) breech chambers in which the solid propellant cartridges were burned identified corrosion as one problem with an indication that stress-corrosion cracking may have occurred. A study was made for stress-corrosion cracking susceptibility of 4340 steel in a paste made of the residues collected from used breech chambers. The constant extension rate test (CERT) technique was employed and SCC susceptibility was demonstrated. The residues, which contained both combustion products from the cartridges and corrosion products from the chamber, were analyzed using elemental analysis and x-ray diffraction techniques. Electrochemical polarization techniques were also utilized to estimate corrosion rates.
Failure Investigations of PH 13-8 Mo Aircraft Components
Authors: Roth M. , Lelièvre C.
Published: May 2019

The failures of two aircraft components, one from a landing gear and the other from an ejector rack mechanism, were investigated. Both were made from PH 13-8 Mo (UNS S13800) precipitation-hardening stainless steel which had been heat treated to the H1000 and H950 tempers respectively and then chromium plated. The parts were characterized metallographically and mechanically and were found to be compliant. Detailed fractographic examination revealed that the first stage of both failures was similar: subsurface initiation of numerous cracks with a wide range of orientations and cleavage like features. The cracking was followed by fatigue in one case and catastrophic failure in the other. Hydrogen embrittlement was identified as the most likely mechanism of failure.
Investigation on a Damaged Propeller Blade
Authors: Pussegoda L.N. , Malik L.
Published: May 2019

The paper describes the findings from a damaged propeller blade made from Mn-Ni-Al-bronze, commercially known as Superston 70 (ABS Type 5). The blade had broken at the 0.65 pitch radius location, and the fracture occurred in a brittle mode. The findings reported here point to two potential contributors to the propeller blade failure, viz., the presence of casting flaws at the low pressure side of the propeller blade and service stresses at this surface that reached approximately 400 MPa. This stress value exceeded the yield strength at the corresponding location of the unbroken blade by approximately 40%.
Corrosion-Induced Failures in Aircraft Components
Authors: Shah Jivan B.
Published: May 2019

A steel eyebolt which attached a rear lift strut to the right wing of a helicopter failed by fatigue. As a contributing factor, thread cutting produced sharp notches at thread roots, reducing fatigue life. Also, design fatigue life may have been exceeded as the part was in use about 10,000 h. Cumulative damage resulting from a previous accident could have occurred too. Because of this accident, inspectors were instructed to examine threaded zones of eyebolts by magnetic particle inspection after every 100 h in service. A maraging steel drive shaft of a helicopter also failed because of corrosion (pits), and continuous abnormal misalignment as well. Corrosion probably developed from moisture and water droplets on shaft diaphragm profiles. Improved diaphragm pack seals and coatings made by an electron-coat process (such as a Sermetal finish) are now used in new shafts.
Failure of a Stainless Steel Bomb Fin Retaining Band
Authors: Pepi M.
Published: May 2019

A bomb retaining ring fabricated from type 302 stainless steel unwrapped during a practice flight, causing the bomb fins to deploy. The retaining ring was able to unwrap itself because it was thinner and softer than required. Hardness testing, metallography, and tensile testing confirmed that the component was in the annealed condition and not in the required work-hardened 1/4-hard condition.
Failure of a Steel Bomb Suspension Lug
Authors: Pepi M.
Published: May 2019

Suspension lugs fabricated from AISI 4340 steel used to facilitate loading of bombs onto the underside of military aircraft could not sustain required loads during routine proof load testing. Three failed lugs underwent visual examination, chemical analysis, metallography, hardness testing, scanning electron microscopy, and energy-dispersive x-ray spectroscopy. It was determined that the failures were due to forging defects. Both forging laps and seams acted as stress concentrators when the lugs were loaded during proof testing.
Failure Analysis of Welded Low-Carbon Steel Storage Tank
Authors: Suess Steven J.
Published: May 2019

Welded steel storage vessels used to hold mildly alkaline solution were produced in exactly the same manner from deep-drawn aluminum-killed SAE 1006 low-carbon steel sheet. After the cylindrical shell was drawn, a top low-carbon steel closure was welded to the inside diameter. The containers were then filled with the slightly alkaline solution, pressurized, and allowed to stand under ambient conditions. A small number, less than 1%, were returned because they began to leak in service. Inspection revealed general corrosion and pitting on the inner surfaces. However, other tanks that experienced the same service conditions developed no corrosion. Corrosion was linked to forming defects that provided sites for localized corrosion, and to lack of steam drying after cleaning, which increased susceptibility to general corrosion.
Corrosion Fatigue, Stress-Corrosion Cracking and Hydrogen-Sulphide Attack of AISI 304 Stainless Steel
Authors: Kenny Philip J.
Published: May 2019

Three separate corrosion mechanisms were involved in the failure of an AISI type 304 stainless steel pipe elbow. The major cracks, including the one that penetrated the wall, tend to be wide-mouthed, tapering to a blunt tip, with corrosion products filling much of the crack space. This was characteristic of corrosion fatigue. The second type of cracking originated at some of the major cracks. These cracks were branched and transgranular, which is characteristic of stress-corrosion caused by chlorides. The third crack mode, an intergranular network, was most probably the result of hydrogen sulphide attack. The 13-year service life of the elbow made it difficult, if not impossible, to determine the order of the corrosion mechanisms or the length of time it took to reach the present state of degradation after the initiation of corrosion. Based on the long service life the present material has given, it was recommended that it be used again.
Metallographic Studies of a Reformer Tube Failure Due to Thermal Fatigue
Authors: da Silveira Tito Luiz , Moreira Francisco Solano , Chavez Miriam Conçeicão Garcia , Le May Iain
Published: May 2019

The failure of a reformer tube furnace manifold has been examined using metallography. It has been shown that the cause of failure was thermal fatigue; the damage was characterized by the presence of voids produced by creep mechanisms operating during the high temperature cycle under high local stress. The study indicates that standard metallographic procedures can be used to identify failure modes in high temperature petrochemical plants.
Damages in Gears in the Transmission System of Heavy Duty Tracked Vehicles
Authors: Chatterjee P. K.
Published: May 2019

Failure occurred in the teeth of a case-hardening Ni-Cr-Mo alloy steel spur gear in the transmission system of heavy duty tracked vehicles. The defects were in the nature of seizure on the involute profile. Scrutiny of the transmission system showed there might be choking in the lubricating oil line. Such would cause seizure of the gears and damage. The incidence of such defects stopped after corrective measures were taken.
Mobile Harbor Crane Wheel Hub Fatigue Failure
Authors: Shirokoff J.
Published: May 2019

Failure analysis of a mobile harbor crane wheel hub that included SEM and EDS analyses demonstrated that the mechanism of failure was fatigue. The wheel hub was a ductile cast iron component that had been subjected to cyclic loading during a ten-year service period. The fracture surface of the fatigue failure also contained corrosion deposit, suggesting that cracking occurred over a period of time sufficient to allow corrosion of the cracked surfaces. Replacement and alignment of the failed wheel hub was recommended along with inspection of the nonfailed wheel hubs that remained on the crane.
Failures of Jib Tie-Bar Components of Tower Cranes Manufactured from Rimming Steel
Authors: Hutchings F. R. , Hanley G.
Published: May 2019

A new crane failed during the overload test following erection. A test load of 5 tons at the end of the jib (rated capacity 4 tons) was in the process of being slewed at the time of this failure. Inspection revealed that the collapse had resulted from the opening out of one eye of the rimming steel tie-bar of the main jib at the lower splice. This permitted the pin to pass through and allowed the jib to fall. Examination subsequently revealed that brittle fracture of two of the corner angles of the tower head assembly had also occurred. Had the tie-bar material been of satisfactory quality and/or, if the end that failed had been flamecut instead of sheared, then the damage resulting from the excessive overload would have been limited to yielding of the material in the region of the pin-joint. Such yielding on an overload test further indicated that the scantlings of the pin-joints were inadequate. Two other crane failures showed that failure resulted from the use of rimming steel, and embrittlement of the material was evident.
Prematurely Broken Valve Spring
Authors: Naumann Friedrich Karl , Spies Ferdinand
Published: May 2019

A valve spring made of 4.1 mm diam wire, designed to withstand 10,000,000 stress cycles, fractured after only 2,000,000 cycles. The surface displayed impressions which indicated it had been treated by shot blasting. The spring has broken in two places. Fracture 1 was a torsional fatigue fracture which has started from a lobe-like surface defect and not, as is usual, from a point on the most highly stressed inner surface. Fracture 2, on the other hand, was a bending fatigue fracture with a starting point on both the inner and the outer surface of the spiral. The objective of the shot blasting, to put the surface into a state of even compressive internal stress, which must first be overcome during subsequent bending and torsional loading before the boundary zone comes under tensile stress, was therefore not realized in this case. On the contrary, the shot blasting led to a state of internal stress which favored fracture of the spring.
Cast Steel Pinion Gear Shafts with Insufficient Elongation
Authors: Naumann Friedrich Karl , Spies Ferdinand
Published: May 2019

The specified elongation of 10% could not be achieved in several hollow pinion gear shafts made of cast Cr-Mo steel GS 35 Cr-Mo 5 3 that were heat treated to a strength of 90 kp/sq mm. The steel was melted in a basic 3 ton arc furnace and deoxidized in the furnace and in the pan with a total of 7 kg aluminum. Fracture of a tensile specimen occurred with low elongation and, apparently, also with low reduction of area. In some places it was coarse grained conchoidal. It was found that the exceptionally low elongation of the cast specimens was due to excessive deoxidation by aluminum.
Fatigue Fracture and Weld
Authors: Naumann Friedrich Karl , Spies Ferdinand
Published: May 2019

Thermal and transformation stresses, resulting from welding, adding up with operational stresses can result in failure. Examples involving the crankshaft of a shaft-drive to produce artificial waves in a swimming pool, the joint bar of a dredger cast out of a running non-alloyed steel with 39 kg/sq mm tensile strength, which had been strengthened by welding plate strips on both sides had fractured in service; an axle tube out of 40 Mn 4 after DIN 17 200 from a paper fabrication machine, which had three short longitudinal slits distributed uniformly over its surface; welding to repair worn out bearing or fits, and a broken rear axle tube of a bus are described.
Fractured Three-Cylinder Crankshaft
Authors: Naumann Friedrich Karl , Spies Ferdinand
Published: May 2019

The fracture cause had to be determined in a three-cylinder crankshaft made of chrome steel 34Cr4 (Material No. 1.7033) according to DIN 17200. The fracture occurred after only 150 h of operation. The fracture was of the bend fatigue type which originated in the fillet of the main bearing and ran across the jaw almost to the opposite fillet of the adjoining connecting rod bearing. The fillet was well rounded and smoothly machined. Thus, no reason for the fracture of the crankshaft could be found externally. No material defects were discernible in the origin or anywhere else. No cause for the crank fracture could be established from material testing. Probably the load was too high for the strength of the crank. Tensile strength could have been increased for the same material by tempering at lower temperature. Additionally, the resistance against high bend fatigue stresses or torsion fatigue stresses could have been increased substantially by including the fillet in the case hardening process.
Fatigue Failures, With Special Reference to Fracture Characteristics
Authors: Cottell G. A.
Published: May 2019

Fundamentals of fatigue failure are outlined. Addressed are fatigue crack characteristics, basic crack types, unidirectional bending, alternate bending, rotary bending, torsion, direct stress, and combined stress. Stress cycle, endurance limits, under and overstressing, stress concentration, and surface condition are discussed. Sections are devoted to fatigue crack assessment, corrosion relation to fatigue failure, and the micro-mechanisms of fatigue failure. Materials considered include steels. Photographs of service failures are used to illustrate features alluded to in the text.
Failure Analysis of a Polysulfone Flow Sensor Body — A Case Study
Authors: Jansen Jeffrey A.
Published: May 2019

A failure analysis was conducted on a flow-sensing device that had cracked while in service. The polysulfone sensor body cracked radially, adjacent to a molded-in steel insert. This article describes the investigative methods used to conduct the failure analysis. The techniques utilized included scanning electron microscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, thermomechanical analysis, and melt flow rate determination. It was the conclusion of the investigation that the part failed via brittle fracture, with evidence also indicating low cycle fatigue associated with cyclic temperature changes from normal service. The design of the part and the material selection were significant contributing factors because of stresses induced during molding, physical aging of the amorphous polysulfone resin, and the substantial differential in coefficients of thermal expansion between the polysulfone and the mating steel insert.
Biologically Induced Corrosion and Consequent Fracture of a Pump Shaft Coupling
Authors: Jur Tim A.
Published: May 2019

During a routine start-up exercise of a standby service water pump, a threaded coupling that joined sections of a 41.5 ft (12.7 m) long pump shaft experienced fracture. The pump was taken out of service and examined to determine the cause of fracture. It was apparent early in the examination that the fracture involved hydrogen stress cracking. However, the nature of the corrosive attack suggested an interaction between the threaded coupling and biological organisms living in the freshwater environment of the pump shaft. The organisms had colonized on the coupling, changing the local environment and creating conditions favorable to hydrogen stress cracking. This paper describes the analysis of the fracture of the coupling and provides an example of how biologically induced corrosion can result in unexpected fracture of a relatively basic machine part.
Biologically Influenced Corrosion of Stainless Steel Welds by Water
Authors: Jenkins C. F. , Doman D. L.
Published: May 2019

Corrosion in a closed-loop cooling water system constructed of austenitic stainless steel occurred during an extended lay up of the system with biologically contaminated water. The characteristics of the failure were those of microbiologically influenced corrosion (MIC). The corrosion occurred at welds and consisted of large subsurface void formations with pinhole penetrations of the surfaces. Corrosive attack initiated in the heat affected zones of the welds, usually immediately adjacent to fusion lines. Stepwise grinding, polishing, and etching through the affected areas revealed that voids generally grew in the wrought material by uniform general corrosion. Tunneling or worm-holing was also observed, whereby void extension occurred by initiating daughter voids probably at flaws or other inhomogeneities. Selective attack occurred within the fusion zone, i.e., within the cast two-phase structure of the weld filler itself. The result was a void wall which consisted of a rough and porous ferritic material, a consequence of preferential attack of the austenitic phase and slightly lower rate of corrosive attack of the ferrite phase. The three-dimensional spongy surface was studied optically and with the scanning electron microscope.
Superheater Components
Authors: Furtado H.C. , Le May Iain
Published: May 2019

Some examples of equipment failures involving high temperature operation are presented. They include some steam generator superheater components and a pump shaft that should not have been at high temperature. Metallographic analysis is used to determine the causes of failure in each case.
Stress Cracks in Brass Pipe Couplings
Authors: Kuhn Karin
Published: May 2019

Brass pipe couplings submitted for examination were deep-drawn from disks then annealed and subsequently cold threaded. Chemical analysis confirmed that the specified alloy Ms 63 was used for fabrication. Some of the pipe already showed fine cracks prior to their installation. In most cases however the cracks were detected after a certain period of operation. The intercrystalline course of the cracks indicated stress-cracking as it often appears in brass after heavier cold deformation. The splitting of the couplings could have been avoided by a tempering heat treatment at temperatures between 230 and 300 deg C after rolling the threads. This procedure would have reduced the internal stresses while maintaining strengthening gained by the cold deformation.
Cracked Pipe Elbow of a Hydraulic Installation
Authors: Naumann Friedrich Karl , Spies Ferdinand
Published: May 2019

An elbow of 70 mm OD and 10 mm wall thickness made from St 35.29, and exposed to 315 atmospheres internal pressure in an oil hydraulic shear installation, cracked lengthwise after a short operating period. Because the stress was not sufficient to explain the fracture of this elbow under this pressure, an investigation was conducted to establish whether material or processing errors had occurred. Microscopic examination showed that a ferritic-pearlitic structure in select locations was very fine-grained. Other signs of fast cooling as compared to normally formed structure of the core zone were noted. It was also possible that the pipe was resting on a cold plate during bending or that it came in touch with a cold tool. This apparently caused the strains at the transition to the cross-sectional part that had been cooled more slowly. The location of the crack at just this point gave rise to the conclusion that it was formed either by the sole or contributive effect of these stresses.
Hydrogen Embrittled Hydraulic Cylinders
Authors: Myron Stuart M.
Published: May 2019

Two types of chromium-plated hydraulic cylinders failed by cracking on their outer surfaces. In one case, the parts had a history of cracking in the nominally unstressed, as-fabricated condition. In another, cracks were detected after the cylinders were subjected to a pressure impulse test. Both part types were made of 15-5 PH (UNS S15500) precipitation hardening stainless steel. Hydrogen embrittlement cracking was the likely cause of failure for both part types. Cracking of the as-fabricated parts was ultimately prevented by changing the manufacturing procedure to allow for a reheat treatment. For parts that cracked after pressure testing, excessive dimensional changes precluded the inclusion of a reheat treatment as a manufacturing step, and further failure was averted by carefully employing proper machining practices, avoiding abusive machining.
Steel Hardenability and Failure Analysis
Authors: Miller Brett A.
Published: May 2019

Hardenability evaluation is typically applied to heat treatment process control, but can also augment standard metallurgical failure analysis techniques for steel components. A comprehensive understanding of steel hardenability is an essential complement to the skills of the metallurgical failure analyst. The empirical information supplied by hardenability analysis can provide additional processing and service insight to the investigator. The intent of this paper is to describe some applications of steel thermal response concepts in failure analysis, and several case studies are included to illustrate these applications.
Hydrogen Induced Cracking of a Tappet Adjusting Screw
Authors: Krishna B.V.
Published: May 2019

The electroplated tappet adjusting screws used in diesel engines failed during initial bend testing. The analysis of the failure showed that the fracture was nucleated from the subsurface of the screw. The fracture surface was intergranular at the ID and OD region and microvoid coalescence in the center. The improper baking after electroplating of the screw led to H2-induced blistering/cracking. The high strength of the threaded region of the adjusting screw increased the failure propensity.
Analysis of Porosity Associated with Hanford 3013 Outer Container Welds
Authors: Daugherty W.L. , Cannell G.R.
Published: May 2019

An unacceptable degree of porosity was identified in several closure welds on stainless steel containers for plutonium-bearing materials. The pores developed in the weld tie-in region due to gas trapped by the weld pool during the closure process. This paper describes the efforts to trace the root cause of the porosity to the geometric conditions of the weld joint and establish corrective actions to minimize such porosity.
On-Site Nondestructive Metallographic Examination of Materials
Authors: Simmons John W.
Published: May 2019

Nondestructive metallographic examination of materials frequently must be performed on-site when the component in question cannot be moved or destructively examined. Often, it is imperative that specific microstructural information (i.e., material type, heat treatment condition, homogeneity, etc.) be obtained either before initial use of a component, or before the use of a component can be safely resumed. In this paper, the use of standard metallurgical laboratory equipment, and the procedures required to conduct nondestructive on-site metallographic analyses of engineering materials, is presented. As an example, the materials and metallographic techniques employed in an actual on-site investigation of a gas tungsten-arc weldment joining two large diameter Ti-6Al-4V alloy cylinders are discussed in depth to illustrate what can be accomplished.
Failure of a Press
Authors: Craft C. Howard
Published: May 2019

An automatic press for making burlap bags had been used for several years. The press failed after being shipped by truck for a distance of about 400 mi. The objective was to determine whether failure occurred during or before shipment. The large piece which broke off the press included a section of the ways and a heavy adjustable mechanism which normally rides on these ways. The weight of the broken section was estimated at several hundred pounds. There was no support for the broken piece beyond the point of breakage. The material was a commercial cast iron, and the largest proportion of the fracture area was fresh and bright. It was concluded that this was a fresh fracture which occurred during shipment, and the crack itself was not present prior to shipment. The fact that a material defect of some sort was present and probably determined the location of the crack was apparently not significant as far as its usage was concerned. The failure could have been avoided by providing support underneath the overhanging member.
Failure of a Flange from a High Pressure Feeder Plant
Authors: Kosec Ladislav , Vodopivec Franc , Wolf Bogomir
Published: May 2019

The flanged bearing bush carrying the drive shaft of a feed pump suddenly fractured after about two years of service. The chemical composition was normal for high chromium ledeburitic cast steel, which was corrosion and wear resistant as well as refractory. For unknown reasons the rotating shaft came into direct contact with the flange. Mechanical friction caused a rise in temperature on both contact surfaces. This mutual contact lasted long enough for the temperature in the contact zone to exceed 1200 deg C, at which the flange material became softened or molten. As a result, considerable structural changes took place on the inner wall of the flange. Thermal stresses and excessive mechanical loads due to smearing of the flange material then led to fracture of the flange.
Failure Analysis of Gas Turbine Engine Fuel Nozzle Heat Shields
Authors: Binard S.C.
Published: May 2019

New type 321 corrosion-resistant steel heat shields were cracking during welding operations. A failure analysis was performed. The cause was found to be chloride induced stress-corrosion cracking. Packaging was suspected and confirmed to be the cause of the chloride contamination. A contributing factor was the length of time spent in the packaging, 21 years.
Shear Band Failures in Threaded Titanium Alloy Fasteners
Authors: Hopple George
Published: May 2019

Failure analysis was performed on threaded Ti-6Al-4V fasteners that had fractured in the threads during installation. Scanning electron microscopy (SEM) and optical metallography revealed that the fractures initiated in circumferential shear bands present at the thread roots. The fractures propagated by microvoid coalescence typical of that observed in notched tensile specimen fractures of the same material. For comparison, Ti-6Al-4V fasteners from various commercial sources were tested to failure in uniaxial tension and examined in the SEM. In all cases, the fracture appearances were similar to that exhibited by the fasteners that failed during installation. In addition, results of optical microscopy indicated that the geometry and extent of the shear bands appeared to depend on the fabrication process employed by the individual manufacturers. Causes of shear band formation are discussed along with potential methods to eliminate these microstructural in homogeneities.
Training teachers in robotics for science and technology dissemination: A Brazilian case study
Authors: Marengo Rafael , Ferreira Bruna , Cabral Morgana , MAGALHES RICARDO R
Published: May 2019

There is a high demand for technical professionals in engineering and related areas, but there are not enough professionals to fill these needs, especially in developing countries such as in Brazil. Abilities of communication, teamwork and leadership are part of the graduating engineers’ curriculum, but students normally have a lack of these abilities due to difficulties in STEM (Science, Technology, Engineering and Mathematics). Many solutions can be implemented in order to change this scenario and robotics is an alternative. Based on that, robotics education as teaching methodology leads students to search for problem logical solutions. This paper is aimed on how robotics can help children learn STEM subjects and presents a training system for robotics involving teachers and students from public schools and tutors from university. As methodology, it was tested the knowledge acquired in weekly meetings between engineering students (tutors) and teachers/students from public schools. Results highlighted the introduction of robotics education in public schools learning process. It can imply on improvements for engineering courses and new robot applications in industries.
Bella Akhmadulina and the Sixtiers: Contacts, contexts, and poems
Authors: Bokarev A. S. , Kuchina T. G.
Published: May 2019

The article offers a close look at Bella Akhmadulina’s poetic dedications to her contemporaries: A. Akhmatova, B. Pasternak, A. Bitov, V. Vysotsky, A. Kushner, and B. Okudzhava. The scholars employ two methods: a bibliographical and a philological one. The former helps to reconstruct the context for Akhmadulina’s interactions with her predecessors and her Sixtiers peers, while the latter, applied to her texts, shows the way in which the dedicatee’s personality and their ties to Moscow or St. Petersburg determine the poem’s metaphors and intonation. A detailed analysis of her dedications to friends and older poets reveals customized, dedicatee-driven communication strategies, as well as invariant features of the poetic dialogue between Akhmadulina and a whole of Russian literature.
Imperial Europeism, or Mikhail Katkov’s truth versus Russian society
Authors: Kantor V. K.
Published: May 2019

The author seeks to destroy the myth surrounding the personality of Mikhail Katkov, one of Russia’s most prominent thinkers and journalists, who defended the Russian imperial ideology, believing it to have descended from European views to take root in the local culture. The author invokes two major figures of Russian history and culture: Peter the Great and the poet Aleksandr Pushkin. Katkov argued that Russia owed its successful integration into European history to Peter the Great, who transformed the country into a powerful empire and created an independent space for spiritual experiments. So it no longer seems accidental that Pushkin was referred to as ‘the singer of the empire and freedom’. It was for that reason that Katkov jumps to the defence of the Russian empire, fearlessly opposing the government, no less, who, he thought, had lost touch with reality. Eventually, Katkov was fighting two enemies: Russian nihilists (with Herzen in the lead), who wasted no time undermining the empire, and Russian liberals, who would stop at nothing, even welcome a foreign invasion, in order to bring down the empire (the so-called ‘Polish intrigue’). The author sets out to reconstruct the writer’s true image through his work.
‘Injin gifts’: Interracial exchange and the image of the white avenger in frontier fiction
Authors: Urakova A. P.
Published: May 2019

The essay focuses on the so called ‘Injin gifts’ – a racialist notion that James Fenimore Cooper attributed to his famous frontier hero Natty Bumppo in The Deerslayer (1841). While implying that certain traits of character, as for example vengefulness, was God’s ‘gift’ to the indigenous people, this notion also paradoxically questions the racial boundaries. The ‘gifts’ are both vertical (bestowed by God) and horizontal (liable to exchange) as Cooper’s novel demonstrates. To support this argument, the essay discusses the plot of racial violence and frontier war in the work of Cooper’s contemporaries – James Hall and Robert Montgomery Bird. Both authors introduce a new cultural hero – a white character who kills indigenous people out of revenge. While revenge is justified as an act of counter-violence, it also threatens to blur the racial boundaries since white characters put on the traits and share the spirit of their antagonists. This is especially evident in Bird’s novel Nick of the Woods (1837): Bird’s racist discourse, paradoxically and unwillingly, turns against itself as his white character Nathan Slaughter engaged in the potlatch-like exchange of violence and deaths, ‘mirrors’ the indigenous Americans he is trying to destroy.
O. Kornienko. Play-element poetics in literature
Authors: Kormilov S. I.
Published: May 2019

The author of the book review argues that, contrary to I. Huizinga’s belief, the play mode of 20th c. literature, especially in its earliest and latest periods, is more pronounced. Russian literature, including its non-official variety, is compared with its foreign peers, starting from antiquity (visual poetry). Along with wide-spread play-elements, the author singles out fairly uncommon ones: to illustrate the use of a lipogram, she references G. Perec’s novel La Disparition (1969), whose 300 pages are written without using the letter e, the most common letter in French. She also follows numerous remarkable features of national or ethnic mentalities reflected in speech. The author describes the principles of encoding, common-usage interpretations, text reductions and thickenings, volume restrictions, etc. She pays special attention to the interaction of literature with non-verbal artistic techniques, especially its synthesis with painting (and more broadly, with images) and music. The book gives examples of the Internet penetrating the system of literary genres.
A poet of oxymora. Sergey Gandlevsky
Authors: Safronova E. V.
Published: May 2019

The article is concerned with the works of S. Gandlevsky and analyzes his selected poems collection Rust and Yellowness [Rzhavchina i zheltizna] (2017). Quoting and conducting an ‘image-by-image’ and ‘plot-by-plot’ examination of Gandlevsky’s best known poems (including ‘To find a job at a motor pool’ [‘Ustroitsya na avtobazu…’], ‘On the Death of I. B.’ [‘Na smert’ I. B.’], ‘Something about the jail and separation…’ [‘Chto-nibud’ o tyurme i razluke…’], etc.), the author summarizes the basis of his poetics: the generous use of cento, oxymoron, a plot that centres around a lyrical hero, a ballad-like quality, as well as a combination of the highbrow and the vulgar, and of the classical and the profane in vocabulary and semantics. Without claiming to have discovered something new about the poet, the article provides a valuable summary, a digest of the main reviews of his work and a critical essence of the key motifs of Gandlevsky’s prose and poetry contributing to Moscow text in Russian literature. In addition, Safronova tries to establish the place occupied by the poetics of the Moscow Time [Moskovskoe Vremya] group in general, and its star member Gandlevsky in particular, with today’s readership.