bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on the Protective Device of Outside Environmental Monitoring System for Refuge Chamber
Authors: Yin Zhong Hui , Zhang Bin Hui , Zhang An Ning , Jing Zi Long , Gu Yu Ming
Published: September 2013

In order to protect the components of monitoring, some measures should be taken when refuge chamber uses outside environmental monitoring system. This paper designs a kind of protective device for outside environmental monitoring system based on related theory analysis and coal mine environment. It can protect monitoring components from gas explosion shock wave. Meantime there is good contact between sensitive element and outside environment to guarantee the normal work of the monitoring system. Finally, this paper builds the model of protective device, and analyses its structural strength.
Research on the Mine Safety Monitoring System Based on Wireless Sensor Network Technology
Authors: Hu Dong Tao , Tao Ting Ting , Liu Zhi Gang , Ren Shao Feng
Published: September 2013

The development of computers wireless network monitoring system mainly includes steps such as the selection of transmission protocol, the calls of database program, data display and automation implementation and so on. The transmission speed of protocol TD-SCDMA is faster. In addition, it also can transmit voice and pure data files. Thus, this article selects TD-SCDMA protocol as transport protocol of wireless sensor networks. On the basis of the software OLEDB, this paper has developed ActiveX Data Object program, and has implemented the safety supervision automation process of wireless sensor network technology. Finally, this paper uses VC++ software to make a numerical simulation experiment on computer programs by taking an example of coal mine gas monitoring. At the same time, through the display on the window, it is the gas concentration monitoring curve that is obtained when the mine safety is abnormal, which provides the safeguard for mine personnel safety and normal work.
Research and Analysis on Injury Factors of College Sports Based on SIIR Survey Instrument
Authors: Li Hai Xia , Zhang Rui Yun
Published: September 2013

In recent years, college is a place where sports injury is the highest and the most frequent. Therefore, it arouses a great concern in the society. In this paper, we use SIIR survey instrument to investigate part of the primary and secondary colleges in Shandong Province. We analyze the determination factors and characteristics of empirical treatment cases of the multiple sports injury. We use data analysis and processing principle of SIIR survey instrument to analyze the characteristics and causes of sports injuries. The multiple regression procedure of SIIR survey instrument is used to build the model. The model is built on the base of the relationship between the age, sex, grade of the students and the injury. We integrate the influence factors of society and college to analyze the sports injury factors. Through the scrutiny of SIIR survey instruments, we can improve the working capacity of the college to prevent sports injuries. We can also reduce the frequency of college sports injuries.
Research and Application of Automation Testing Technology Based on Keyword-Driven
Authors: Guan Xiao Juan , Zhou Cheng , Qian Xuan Yu , Liu Shi Min
Published: September 2013

With all kinds of structured data and unstructured data between intranet and external information network interacted frequently, a kind of safety device has been produced that achieved effective control of information network data access to ensure normal operation of the isolation system and related business and make the data of intranet safe and reliable. In order to ensure that every release version could run stability, automation testing solution based on keyword driven has been designed to realize the separation of test data, test scripts and test logic. The main design were keyword structure and hierarchical key separation. Regression testing has consisted of test Cases configured flexibility and selectively to realize reasonable arrangement of testers and improve test efficiency.
Research and Implementation of Key Techniques of Osgi Integration Testing Platform
Authors: Liu Fa Gui , Peng Yu Song , He Nan , Yang Ying Yi , Yang Jin , Zhang Xiao Ke
Published: September 2013

The innovation and development of software and information technology has stimulated the mature of service-oriented architecture (SOA) platform technology, while the loosely coupled, modular, dynamic loading feature of OSGi service platform has made itself a popular architecture within the SOA community. To embody the advantages of the OSGi framework application with a longer lifecycle and ensure the quality of OSGi applications, we need to run a series of rigorous testing, especially integration testing. Existing tools do not support separation of testing and development, testing records playback or redundant test cases auto-generation. In this paper, we have analyzed the current OSGi testing techniques and tools as well as their inadequacies. Our research into OSGi testing technology has enlightened us to expand the function of the testing tools on the basis of Pax-exam and then integrate them into the OSGi testing platform. Finally, we discuss the framework design of our OSGi integration testing platform and demonstrate the correctness and validity of the platform.
Study on Fault Diagnosis and Repair Strategy of CNC Machine Tool
Authors: Lin Guo Min , Shang Miao , Zhang Wen Guang
Published: September 2013

CNC machine tool fault types, repair characteristics, the principle to be followed are described. The mechanical systems, Numerical control system, servo system fault diagnosis and repair for CNC machine tools are analyzed in detail. The strategy of the hardware faults such as main spindle part, the ball screw-nut pairs, cutter and tool change device, the strategy of the software repair are proposed.
Influence of Composition and Processing on Properties of Stainless Steels
Authors: Narahari Prasad S. , Rajasekhar K. , Chatterjee M.
Published: September 2013

Stainless steels, by virtue of their diversity in chemistry, microstructure and properties, find widespread applications ranging from domestic appliances to high technology sectors such as space, aeronautics, power, chemical and ordnance. Midhani has been at the forefront of material development over the past few decades and has produced several stainless steels, tailor made for specific critical applications. Subtle variations in chemistry or processing methodology have been exercised to achieve the desired microstructure and properties. In this context, influence of minor addition of austenitic stabilizing element on structure and properties on conventional ferritic stainless steel SS430 was studied. The chemistry modification changed the structure to dual phase, austenite ferrite structure, that responded to heat treatment by transformation of austenite to martensite. This dual phase structure after tempering enhanced the strength and toughness by 25% and 60% respectively. In the case of 13-8 Mo PH stainless steel, a modified two stage solution treatment and ageing resulted in enhancement of toughness by over 100% as compared to conventional single stage solution treatment and the improvement was attributable to refinement in martensitic sub-structure due to thermal cycling. With respect to SS 440C, a high carbon stainless steel, the performance is closely related distribution of primary carbide. Bearing directly manufactured from forged stock produced from ingot do not perform satisfactorily in view of massive primary carbides present in the form of stringers / bands. This problem was addressed by subjecting the forged stock to further working in the transverse orientation by ring rolling which brought about finer primary carbides. The present paper highlights some of the challenges and the modifications brought about to meet the specific needs.
Stainless Steel Processing to Meet Advanced Applications
Authors: Balachandran G. , Balasubramanian V.
Published: September 2013

Stainless steel bar and wire products that cater to the high technology application in defence, nuclear, aerospace, oil field and chemical engineering is an area poised for rapid growth in India. The advancing capabilities of alloy steel plants in India have enabled mastering of techniques to make a wide variety of stainless steels. However, there are increasing challenges to meet the advanced property requirements, which call for a basic understanding on the structure property relationship that are influenced by appropriate alloy design and down-stream processing. The special steel industry cater to a wide variety of stainless steels namely ferritic, martensitic, austenitic and precipitation hardenable categories for meeting requirements of high technology. One of the process for making the primary stainless steels is Vacuum Oxygen Decarburisation process. For advanced applications, the primary melted steel is again secondary refined using electroslagremelting for the management of solidification structures and control of inclusions. In the austenitic grades, the hot forged and hot rolled heat treated steels, careful choice of chemistry controls the delta ferrite content and ensures uniformity of the grain size in the product during deformation processing and heat treatment. In the martensitic stainless steel grades, focus is given to delta ferrite, grain size control and appropriate tempering treatment. In the precipitation hardenable steels grades the aging reactions and hot deformation range have to be optimised for deriving specified mechanical properties. Special grades are produced using non ESR and ESR routes to meet high temperature applications such as turbine blades and bolting. In these grades control of delta ferrite content, carbides, carbo-nitrides in the matrix has a deep influence on the mechanical and sub zero fracture properties. In the ferritic stainless steel grade grain size control is critical. The presentation would bring forth the correlation between the alloy design, processing and properties that were achieved in the products mentioned above to meet some of the challenging requirements.
Experiences in Manufacturing and Qualifying of Stainless Steel AISI 403 Grade Materials for PHWR Reactors of NPCIL
Authors: Jain J.K. , Singh Sundar , Mathur M.K. , Srivastava N.P. , Dwivedi K.P.
Published: September 2013

NPCIL uses stainless steel AISI 403 grade material extensively for very critical nuclear components. A very special application of this material is for manufacturing END FITTING BODY of COOLANT CHANNEL ASSEMBLIES of Pressurized Heavy Water Reactor (PHWR) of Nuclear Power Plants. Presently, two types of PHWR Nuclear Plants viz 220 MWe and 540 MWe are under operation in India. Next higher rating viz 700 MWe PHWR Nuclear Plants are at various stages of construction and due for commissioning in near future.
There are number of Pressure Tubes in PHWR Nuclear Plants wherein fuel is loaded and are called coolant channel assemblies. End fitting bodies are assembled on either end of PRESSURE TUBES of coolant channel assembly. The Coolant (Heavy water) flows inside these assemblies and collects the heat produced during nuclear reaction in pressure tubes. This heat is utilized to produce Steam in Steam Generators. After giving up heat in Steam Generator, coolant returns to pressure tube and cycle continues.
Material for End Fittings has been selected keeping in mind the mechanical properties at room and at elevated temperatures are compatible with mating component which are manufactured using Zircaloy and SS 410. It is also an essential that coefficient of thermal expansion is also compatible for mating material.
Indigenization of the material for manufacturing of End Fittings with short delivery period has always been a challenge for commercial Nuclear Reactors. Inspection of these types of critical nuclear reactor components becomes critical due to the high safety standards and complexity in structures. There are very few manufacturers for this material in India. NPCIL took up a challenge for developing a new supplier in Northern Region of India for developing this material. A leading company in northern region of INDIA came forward and took up the challenge and succeeded for this venture.
This paper deals with development of vender to manufacture of AISI 403 grade material by melting, refining ( ESR process), forging, heat treatment, testing & provide the guidelines to tackle the issue faced during this developmental work.
Development of Heat Treatment Parameters to Enhance HAZ Impact Toughness of SS 430 Material
Authors: Raj Kumar R. , Patle Surendra
Published: September 2013

Pressure Housing, used in the Grid Mechanisms Motor, is manufactured from ferritic stainless steel, SS430 bar of 120mm diameter. The application demands an alternative non-magnetic and magnetic material (austenitic and ferritic) on the outside. This is manufactured by making longitudinal machined slots on the outside surface of SS430 bar which is ferritic and magnetic and the machined slots are filled up by depositing SS347 which is an austenitic and non-magnetic stainless steel material. In order to weld SS430 # SS430 with SS347, welding procedure was to be qualified as per ASME Sec IX with additional requirements of impact specimens from weld and HAZ at temperature +20°C, microstructure examination and intergranular corrosion test as per ASTM A763 Pr.Z. It was the first time, SS430 # SS430 welding procedure qualification with SS347 was to be carried out as no earlier cases required this qualification. SS430 ferritic stainless steel bar exhibits stringers of ferrite and martensite and in cases of stingers of two phase structures like duplex stainless steel, it has been reported that the transverse impact properties drops to half to two-third the longitudinal values. In the welded coupon, the impact property on the HAZ was located in the transverse direction and extremely difficult to meet the requirements. Welding qualification with impact requirement in transverse direction in HAZ was a challenging task and this paper addresses the issues encountered and the work carried out in literature study on the metallurgy, heat treatment and experimental trials to meet the specification requirement.
Trans- Granular Stress Corrosion in Partially Fabricated Austenitic Stainless Steel Items and their Re-Conditioning to make them Suitable for Balance Fabrication
Authors: Saxena G.K. , Master M.M. , Srivastava N.P. , Dwivedi K.P. , Iyer G.R. , Mistry Anand
Published: September 2013

Fabrication of various sub assemblies and items from imported austenitic stainless steel material of SA 240 - 304L (32 mm to 85 mm thick) was started in the year 1990 and work on these assemblies was stopped in 1993 due to unavoidable circumstances. Items and sub-assemblies were either in partially welded / machined or formed condition. Sub assemblies / items were stored in open yard for 13 years after applying plastic peal coating compound and covered with tarpaulin. The storage yard was near to the sea (roll on & off Jetty) as well as next to petrochemical industries. Sub assemblies have seen different extreme weathers conditions, saline and corrosive atmosphere for all these years and during this storage time base material and welded joints were subjected to contamination.
Performance of Multilayered PVD Coated Cemented Carbide Inserts during Dry Turning of AISI 304 Austenitic Stainless Steel
Authors: Kulkarni Atul P. , Sargade Vikas G.
Published: September 2013

AISI 304 austenitic stainless steel is generally “difficult-to-cut” material than other types of steel on account of their high strength, high work hardening tendency and poor thermal conductivity. The focus of the paper is on the dry, high speed machining which is ecologically desirable and cost effective. It is also the future of machining and called as green machining. PVD multilayered TiN/TiAlN and TiAlN/TiSiN coated inserts were used for dry, high speed turning of AISI 304 austenitic stainless steels material. TiN/TiAlN coating was deposited using “Cathodic Arc Evaporation” (CAE) technique where as TiAlN/TiSiN coating was deposited using “Closed-Field Unbalanced Magnetron Sputtering” (CFUBMS) technique. Coatings are deposited on K-grade (K-20) cemented carbide insert. Scanning Electron Microscopy (SEM), microhardness tester and scratch tester were used to examine microstructure, microhardness and adhesion of coating. The thickness of the both coating was found to be 3.8 ±2 µm. TiN/TiAlN coating demonstrated micro-hardness value 34 GPa where as TiAlN/TiSiN coating shows 37 GPa. The adhesion strength of the TiAlN/TiSiN coating is 86 N and that of TiN/TiAlN coating is 83 N.The turning tests were conducted in dry machining environment at cutting speeds in the range of 100 to 340 m/min, feed in the range of 0.08 to 0.20 mm/rev keeping depth of cut constant at 1 mm. The influences of cutting speed, feed and tool coating were investigated on the machined surface roughness, flank wear and cutting force. TiAlN/TiSiN coated tool showed better performance and exhibited lower cutting forces than TiN/TiAlN coated tool. Built-up edge was not observed during using coated tool due to better thermal stability of the coating. The research work findings will also provide useful economic machining solution in case of dry, high speed turning of AISI 304 stainless steel, which is otherwise usually, machined by costly PCD or CBN tools. The present approach and results will be helpful for understanding the machinability of AISI 304 stainless steel during dry, high speed turning for the manufacturing engineers.
Challenging Experiences in the Usage of Stainless Steels in a Heavy Fabrication Industry
Authors: Gurunathan T.
Published: September 2013

Stainless steels are regularly used as one of the preferred material of construction in the pressure vessels and heat exchangers manufactured by welding for process plants and energy sector at BHEL, Tiruchirappalli. They are considered mainly because of their corrosion resistance and high temperature suitability. But the practising welding engineers have to face innumerable challenges with stainless steel with regard to defects minimization, distortion control and dimensional stability on large and complex assemblies. Use of Nickel based filler wires or development of welding procedures simulating the true configuration of the product and by conducting specific tests and NDE are followed for weld defects control. Sequence welding, development of special fixtures, etc have come as handy options for welding distortion control of SS. Innovative inspection techniques for the certification of dimensions including geometrical tolerances especially on large constructions using SS welding and evolution of special Helium leak testing procedures for certain in-process checks in critical products are inevitable in the SS fabrication industry as a part of Quality Assurance programme. As a pioneer in SS fabrication, some of our challenging experiences pertaining to these three areas are discussed in this paper.
Stainless Steel Welding in Railways
Authors: Ravichandran R.
Published: September 2013

Railways form the lifeline of the transport network in our country. Indian Railways command a large market share of the over-land passenger and freight traffic. To sustain this, rail industry is required to technologically and commercially challenge superior highways and advanced technology of road vehicles and also the competitive airlines. Thick and thin sheet metals are widely used in wagon and rail car body fabrication respectively. Rail coach manufacturing sector is in the new challenging phase due to acquirement and adoption of German and Korean technologies and arrival of multinational companies viz M/S Bombardier & M/S Alstom. Thin sheet metal fabrication demands aerodynamic profiles larges size bodies with high level of aesthetic and dent free surface. Thick sheet metal fabrication demands larges size bodies with high level of structural rigidity and dimensional stability .The outer skin of the rail coach body is generally made through thin sheet metal parts and stiffened with moldings, pressings and stamped sections. In the recent past rail car manufactures has been switching over from HSLA steel to stainless steel to acquire the benefit of the later: primarily corrosion resistance Capability and durability and ease of maintenance. The manufacturing practices, challenges addressed during fabrication are brought out.
SS Manufacture - Indian Practice and Electrical Perspective
Authors: Muralinath C.N.
Published: September 2013

The major route for SS production has been via EAF. The challenge of decarburising the melt with oxygen in the presence of high levels of chromium has been handled through AOD and VOD processes. In plants manufacturing other alloys as well as SS, high carbon liquid steel is produced in the EAF, without any chromium addition. All Chrome addition takes place in the AOD, increasing the process time, cost, temperature and refractory wear. EAF has high oxygen consumption and foaming arc allowing long arcs. In SS plants, the EAF charge consists of SS/MS scrap high C ferrochrome. Minimal oxygen is used and 85% of energy is electrical. Foaming slag practice has not been successful till now. Short arc lengths are used. Proper choice of Electrode Regulation System and Smart Furnace Melt program are essential. Modern Electrode Regulators are similar in regulation speeds. Hence the choice must be based on the diagnostic and analytic features and other special features which can eliminate VCB trippings and Electrode breakages. Improvements can be achieved in some areas. Electromagnetic Stirring will help in reducing arcing time, lining wear and allow longer arcs. Possibilities of modifications to the shell to allow foaming slag practice should be explored. Waste heat recovery using high temperature quenching and evaporative cooling to generate steam can be adapted.
Production of High Nitrogen Stainless Steel X8CrMnN18-18 through EAF-AOD-LRF-CC-Steckel Mill Route and its Hot Deformation Study by Gleeble Thermomechanical Simulator
Authors: Patra Sudipta , Singhal Lokesh Kumar
Published: September 2013

High nitrogen containing austenitic stainless steel X8CrMnN18-18 exhibits attractive combination of high strength, toughness and corrosion resistance.This grade containing more than 5000 ppm of nitrogen was produced commercially through EAF-AOD-LRF-CC-Steckel mill route and its microstructure and mechanical properties were studied. Excellent combination of strength,ductility and toughness is achieved in the entire range of 6mm to 50mm thick hot rolled plates. Uniaxial compression tests were carried out to understand the hot deformation behavior by varying temperature and strain rate. Softening behavior during deformation was analyzed from flow stress strain curves and microstructural analysis. Dynamic recrystallization (DRX) behavior of the material was observed during thermo mechanical processing. Critical strain related to DRX and Avrami kinetics of DRX was calculated by analyzing the flow curve data. Microstructural characterization was done by optical microscopy and EBSD analysis. Extensive grain refinement can be achieved by thermo-mechanical processing controlled by DRX. Keywords: High nitrogen stainless steel, Strength and toughness, DRX, Grain refinement, TMCP
Thermodynamic Stability of Fe-Cr Binary System: The Crucial Role of Magnetic Contribution as Elucidated by Calorimetric Measurements
Authors: Hajra R.N. , Raju S. , Rai A.K. , Tripathi H. , Saroja S. , Jayakumar T.
Published: September 2013

The influence of magnetic interactions on high temperature thermodynamic stability of Fe-Cr binary system has been analysed in the light of accurate isothermal calorimetry measurements (400-1473 K) on Fe-20wt.%Cr alloy. The onset of two successive principal transformations namely, (i) α(Fe-rich bcc)+α(Cr rich bcc)α(HT bcc) at 702±10 K; and (ii) αferroαpara at 925 ±10 K, with their associated enthalpy effects (ΔoHmag = 2 kJ mol -1; Cpmag = 20 J mol-1 K-1) have been clearly delineated by the measured enthalpy variation with temperature. A precise quantification of magnetic contribution to high temperature thermodynamic stability has been attempted using physically based modelling approach.
Stress Corrosion Cracking of Duplex Stainless Steels
Authors: Chattoraj Indranil
Published: September 2013

The relative superiority of duplex stainless steels (DSS) over austenitic grades with regards to stress corrosion cracking (SCC) is discussed. The benefits of N to SCC resistance of DSS are provided. The selective dissolution of phases and its impact on corrosion SCC is reviewed. The hydrogen embrittlement of DSS is reviewed with emphasis on the ferrite participation, the role of environments and fracture morphology. The evolution of secondary phases and precipitates and the resultant change in corrosion resistance and SCC in DSS is discussed.
Use of Advanced Austenitic and Duplex Stainless Steels for Applications in Oil & Gas and Process Industry
Authors: Kangas Pasi , Chai Guo Cai
Published: September 2013

Stainless steels are widely used in the Oil & Gas and chemical process industry. This group of materials is today available in a large variety of alloy compositions, and practically all product forms needed for a construction are available. A historical view and application examples are given on the stainless steel evolution, from the standard grades used in chemical processes to todays most advanced applications in the chemical and oil & gas industry, where demands on reliable and long lasting solutions are necessary. The influence of alloying elements on the properties and manufacturability is described. The chemical industry is a very wide definition of a large group of industries with very different products, from plastics and organic acids to fertilizers, drugs and pesticides. Applications of stainless steels within the chemical industry are described. The first example is organic acids, where the use of high alloyed duplex stainless steels such as UNS S32205 and UNS S32750 have been successful. Another example is phosphoric acid applications, where the aggressiveness of the process solution depends very much on the fluoride and chloride content of the rock phosphate. In sulfuric acid, the material of construction is very much dependent on the acid concentration and temperature. Nitric acid is another common fertilizer acid which is highly oxidizing, and thereby demands stainless steels with high chromium content but with low molybdenum contents. The Oil & Gas industry uses very high quantities of carbon steel and stainless steel in their constructions. The oil wells are defined as sweet when the well contains carbon dioxide and no substantial amounts of hydrogen sulfide, when there is hydrogen sulfide present in the well, the wells are defined as sour. An overview on materials depending on the application is given. In subsea applications, hydraulic control lines (umbilicals) are used for control of valves and for methanol injection in subsea platforms. UNS S32750 is a high strength duplex stainless steel which today is the first choice for umbilicals and has been chosen for a very large amount of umbilical projects worldwide. The newly developed hyper duplex stainless steels with a combination of even higher corrosion resistance and strength are introduced for applications in oil-gas industry. The possibilities with stainless steels are endless, and new alloys are constantly being developed to meet industrial challenges of today and in the future. By choosing the right stainless steel grade, it is possible to find a solution to almost all challenges in the Oil & Gas and Process industry.
Degradation/Damage Modes and their Control Measures for Stainless Steel Components in Chemical Plants
Authors: Nakahara Masao
Published: September 2013

Safe and continuous operation of chemical plants is the most important issue for sustainability of chemical enterprises. The control and prevention of degradation/damage on components used in chemical plants are indispensable for this purpose. Although varied types of material, such as stainless steels, Ni-based alloys and reactive metals, are in use to control these phenomena in plants, various cases of degradation/damage have actually been experienced and the accidents caused by such degradation have occasionally been reported. In order to prevent such uncontrolled degradation, it is thought necessary to predict the likelihood of degradation of materials under actual operating conditions, to use compatible materials, to detect the degradation by inspection in advance and to apply proper countermeasures based on realistic life estimation of the plant concerned. In order to follow these processes properly, extensive accumulation and orderly organization of knowledge about the mechanisms on degradation/damages, characteristics of materials, inspection technics and methods of plant life estimation are thought of vital importance. As stainless steel is the commonly used material in chemical plants, sufficient accumulation of informattion and knowledge about the stainless steel components to be used is considered the most important subject to prevent the degradation/damage in chemical plants. This paper enumerates the characteristics of commonly encountered modes of degradation with stainless steel components in chemical plants and presents some cases of the degradation/damage on stainless steel equipment in plants, together with control measures required to prevent such degradation. The present-day problems of materials engineering relating to the reliability of chemical plants and the countermeasures against degradation/damage are also presented.
Comparative Evaluation of 316L and N-Bearing Ni-Free Austenitic Stainless Steel as a Potential Cost-Effective Replacement for Body Implants
Authors: Poojary Prashant , Singhal L.K.
Published: September 2013

Currently austenitic stainless steels, cobalt-chromium alloys and titanium alloys are used in body implants. As per ISO 5832-1, Cr-Ni-Mo alloy 316L with minimum 13% nickel is widely used for body implants. ASTM standard F 2229-07 also permits nitrogen strengthened essentially Ni-free Cr-Mn-Mo alloy (UNS S 29108) for this purpose. Nitrogen as austenite stabilizer is able to substitute nickel. It serves the dual purpose of increasing the strength as well as pitting corrosion resistance. This paper compares the corrosion behaviour of these two grades. Cyclic potentiodynamic tests were carried as per ASTM F2129 in Simulated Body Fluids (SBFs) like Ringers, Hanks and Phosphaste Buffer Saline solution at 37 °C, which corresponds to the human body temperature. The pitting potential was significantly higher for Ni free grade S29108 as compared to 316L. In addition, re-passivation potential of the S 29108 was also far superior than 316L. The reverse scan indicated that the breakdown of the passive film was not reached in S 29108, whereas a hysteresis loop was observed in 316L. The strength of annealed S 29108 is far superior and meets the property requirement of ISO 5832-1 for 316L under cold rolled conditions. Thus this alloy could replace annealed as well as cold rolled 316L as per ISO 5832-1. This promising alloy has an added advantage of being significantly cheaper as compared to 316L and other Ti, Co based alloys to enable cost effective medical care to common man. Keywords: High nitrogen stainless steel, 316L, Bio-Implants, Potentio-dynamic tests.
Development of 216L for Conservation of Nickel & Molybdenum and its Application in Sugar Refinery Instead of 316L
Authors: Singhal L.K. , Poojary P.
Published: September 2013

Development of an austenitic Fe-Cr-Mn-Ni-Mo-Cu-N alloy 216L to substitute AISI 316L for saving a part of expensive nickel and molybdenum is described. Nickel content is reduced by 40% and molybdenum by 25% with the help of nitrogen, manganese and copper additions. Corrosion tests in boiling solutions in a variety of acidic media including oxalic, nitric, phosphoric, sulfuric and chromic acids and polarization curves in acidic and chloride environment indicate similar behaviour of both grades. There is also striking similarity in pitting corrosion resistance and inter-granular corrosion resistance of the two alloys as per ASTM G-48 and ASTM A262 respectively. Both alloys exhibit excellent resistance to any staining in prolonged salt spray test. Produced by conventional EAF-AOD-CC-Steckel Mill route, the alloy exhibits surface quality comparable to AISI 316L in both hot and cold rolled conditions. Like 316L, it is equally amenable to fabrication and welding. Higher yield strength of 216L confers potential for material saving in use as compared to 316L. In the process of extracting refined sugar from raw sugar a number of chemicals are used. Accumulated scale from the equipments is periodically removed by using hot solutions containing caustic soda and soda ash followed by rinsing in solutions containing dilute hydrochloric acid and finishing with water rinse. The steel generally used is 316L and based on comparative performance of 216L this new alloy was successfully used in sugar refinery columns where it is subjected to periodic cleaning by hot salt & caustic soda solution and hot dilute hydrochloric acid.. Key words: nickel conservation, 216L austenitic stainless steel; corrosion resistance, sugar refinery
Temper Embrittlement and Corrosion Behaviour of Martensitic Stainless Steel 420
Authors: Chandra K. , Kain Vivekanand , Srinivasan N. , Samajdar I. , Balasubrahmanian A. K.
Published: September 2013

Tempering of alloy steels in the temperature range of 400-600 °C causes temper embrittlement i.e. decrease in notch toughness of the material and the nil ductility temperature is raised to room temperature and above. The fracture in temper-embrittled steel is intergranular and propagates along prior austenitic grain boundaries. The embrittlement occurs only in the presence of specific impurities, e.g. P, Sn, Sb and As. These elements have been shown to segregate along prior austenite grain boundaries during tempering. Similar type of temper embrittlement can occur in martensitic stainless steel (SS) if tempered in the temperature range of 450-600 °C. This paper reports a case of failure of components made from martensitic SS 420 due to temper embrittlement. These components were subjected to a temperature of 120 °C in the initial stages of service and had shown brittle fractures. Scanning electron microscopic examination of the fracture surface of both the components showed intergranular fracture. The microstructures of the failed components confirmed that the materials were in hardened and tempered condition. In addition, the microstructure revealed both intergranular corrosion (IGC) and intergranular cracking. The electron backscatter diffraction study also showed retained austenite in the first components material. The material undergoing IGC might be related to a wrong heat-treatment during fabrication and subsequent pickling procedures. To confirm this, a sample each from both the components was exposed to 5% nitric acid solution at 25 °C. The results showed very high corrosion rate and the attack was intergranular in nature. The failure of both the components was concluded to be due to wrong tempering treatment in the temperature range of 450-600 °C that cause grain boundaries to become susceptible to embrittlement and corrosion.
Manufacture of Specialty Stainless Steels through Triplex Route at Mukand
Authors: Nair Sunil , Savio Dominic , Srinivas Y. M. , Srinivasan K.R.
Published: September 2013

Specialty stainless steels designed with higher levels of Chromium, Nickel and Molybdenum than the general austenitic grades AISI 304 and AISI 316 have distinctly superior corrosion resistance properties. The commercial production of such high alloyed stainless steels came with advent of improved steel melting, refining and casting technologies. These technological improvements made it possible to produce such steels with low carbon levels and close control of chemical composition necessary to achieve the desired phase balance and avoid formation of undesirable intermetallic phases. Further, ability to achieve low sulphur levels combined with freedom from undesirable level of tramp elements improved the hot workability characteristics. Thermodynamic aspects of steelmaking and refining in Vacuum Oxygen Decarburization ( VOD) process for manufacture of specialty grades 904L (24% Ni, 20% Cr, 4% Mo, 1.2%Cu) , 317LM ( 19% Cr, 14.5% Ni, 4% Mo,) , 2205 ( 22.5% Cr, 5% Ni, 3% Mo) at Mukand through the Triplex process route ( Ultra High Power Furnace Oxygen Top and Bottom Blown Convertor VOD) are outlined. The effects of undesirable intermetallic phases, particularly sigma phase, on mechanical and corrosion properties are discussed. Application areas for such specialty grades are reviewed. Keywords: High alloyed Stainless steels, triplex process, sigma phase, intermetallic phases, tramp elements, hot workability, corrosion properties, vacuum oxygen decarburization.
Characterization of Porous Aluminum Fabricated via Sintering-Dissolution Process (SDP)
Authors: Jamaludin Shamsul Baharin , Rushdi Nik Mohd Fikry Mohd , Abdullah Alida , Hussin Kamarudin
Published: September 2013

Porous metals that have open pores structure with low density and light weight properties are suitable to be used in many engineering applications. In this work, the porous aluminum was fabricated via sintering dissolution process (SDP). Aluminum and sodium chloride (20, 40, 50 wt. %) powders were mixed together to produce a homogeneous mixture. The mixture was compressed at 200 MPa followed by sintering at 500 °C, 550 °C and 600 °C for 2 hours. The sintered samples were placed under a warm running water stream for 45 min to dissolve the sodium chloride that embedded in the aluminum. From the result, the sodium chloride content controlled the total porosity between 20% and 40% of the sintered aluminum. Porosity increased and compressive strength decreased as the content of NaCl increased. It was also observed, the porosity increased with increasing sintering temperature for the sample with 40 wt. % of NaCl.
Annealing Effect on Small Molecules Blend Organic Light-Emitting Diodes
Authors: Mohd Sarjidan Mohd Arif , Basri Siti Hajar , Abd Majid W.H.
Published: September 2013

This research work investigates the influence of the annealing process upon the performance of photo-emissive layer of organic light-emitting diode (OLED). The photo-emissive layer consists of a ternary blend of N, N-diphenyl-N,N-bis (3-methylphenyl)-(1,1-biphenyl)-4,4-diamine (TPD), 2-(4-biphenylyl)-5-phenyl-1,3,4-oxadiazole (PBD) and tris-8-hydroxyquinoline (Alq3), to produce TPD:PBD:Alq3 (at 1:1:1 ratio) blend thin films, in which the material solutions are deposited onto clean substrate via spin-coating method. The samples were annealed at 100°C in 10, 20 and 30 minute of time in an open-air condition. The results reveal that the annealing process at 10 minutes produces an optimum performance of the ternary OLED.
Physical and Morphological Properties of Styrene Butadiene Rubber / Recycled Chloroprene Rubber (SBR/CRr) Blends
Authors: Azrem Ahmad Azmi , Noriman N.Z. , Razif M.N. , Sam S.T. , Saiful Nizwan M.S.
Published: September 2013

The effects of physical and morphological properties of styrene butadiene rubber/virgin chloroprene rubber blends (SBR/CRv) and styrene butadiene rubber/recycled chloroprene rubber blends (SBR/CRr) were investigated. Both SBR/CRv blends and SBR/CRr blends were prepared using two roll mill at room temperature with blend ratios 95/5, 85/15, 75/25, 65/35 and 50/50. The range size of CRr used in this study was 0.3 0.7 mm. The SBR/CRr blends shows higher value of hardness and crosslink density compared to SBR/CRv blends at all blend ratios. The scanning electron microscopy (SEM) of tensile fracture surface of SBR/CRr blends at 15 blend ratio illustrated a better adhesion and dispersion of CRr with SBR matrix compared with SBR/CRv blends.
The Development of Cement Composites Reinforced Coconut Fiber with Fly Ash Addition: Mechanical Properties and Fracture Behavior
Authors: Nadzri Nur Izzati Muhd , Jamaludin Shamsul Baharin , Mazlee Mohd Noor
Published: September 2013

This research paper presents a study on the development of cement composites reinforced coconut fiber with fly ash addition. Various content of coconut fiber (3 wt. %, 6 wt. %, 9 wt. %, 12 wt. % and 15 wt. %) was added to the cement composites composition as reinforcement. Additions of 20 wt. % fly ash and 80 wt. % of sand were used as a mixture of cement matrix. Water to cement weight ratio ranging from 0.55 to 0.70 was used in the cement composites to maintain workability. The cement composites were then cured for 7, 14 and 28 days. The result is presented in terms of compressive strength, modulus of rupture and fracture behavior.
Effects of NR and Liquid NR Loading on Swelling Behaviour of TPU/NR Blends
Authors: Ahad Nor Azwin , Ahmad Sahrim Haji , Zain Norazwani Muhammad
Published: September 2013

The blends of thermoplastic polyurethane (TPU) with natural rubber (NR) at four different blend ratios were prepared via melt blending at 180°C and 190°C, with addition of liquid natural rubber (LNR) as compatibilizer. The effect of blend ratio and temperature swelling index was studied. The equilibrium swelling index of TPU and its blend increase with increasing of NR, because of the easiness for solvent to diffuse into the gap between rubber molecules. The temperatures of blending also give effect to swelling behavior. Swelling index of all samples was higher when mixed the blends at higher temperature.
Structural, Optical and Antibacterial Properties of ZnO Commercial Powder Grades
Authors: Sirelkhatim Amna Hassan , Mahmud Shahrom , Azman Seeni , Dasmawati Mohamad , Habsah Hasan , Sendi Rabab Khalid , Bakhori Siti Khadijah Mohd. , Ann Ling Chuo , Rahman M. Aizuddin A.
Published: September 2013

We investigated the structural, optoelectronic and antibacterial properties of two commercial ZnO powder namely White (rubber grade) and Pharma (pharmaceutical grade) in order to study the correlation between the structural-optical property and the antibacterial efficacy. Transmission electron microscopy (TEM) micrographs showed rod-like morphology for the Pharma specimen and grainular shape for the White sample. X-ray diffractometry (XRD) results confirmed the superior crystallinity of the Pharma powder and photoluminescence (PL) data also showed higher UV photocatalysis of the Pharma powder if compared to that of White powder. Using the broth macrodilution method to determine the antibacterial activity of ZnO specimens, we discovered the Pharma grade exhibited stronger inhibition (80-98%) on the growth of Escherichia Coli (E. coli) especially for the ZnO suspension concentration of 10-20 mM. We believe that the superior crystallinity and stronger photocatalysis of the rod-like Pharma powder could have generated much more reactive oxygen species (OH-, H2O2 and O22-) than that of White sample resulting in the higher growth inhibition of E.coli. This work also highlights the impact of rod-like primary particles of Pharma powder in exhibiting good antibacterial efficacy if compared to the grainular particles of White powder and this observation justifies the usage of ZnO Pharma powder in pharmaceutical and healthcare products.
Structural and Morphological Studies of Cadmium Sulfide Nanostructures
Authors: Lahewil Abdulwahab S.Z. , Al-Douri Y. , Hashim U. , Ahmed Naser Mahmoud
Published: September 2013

Cadmium sulfide (CdS) nanostructures were prepared with different spin coating speed 1000 and 3000 rpm and molarities of Cd:S to be 1.2 to 0.01 mol/L using sol-gel spin coating technique. It is found that the average grain size of CdS nanostructures deposited on glass substrates at 1000 and 3000 rpm is 43 to 4 nm respectively. The effect of grain size on the semiconductor properties are in agreement with experimental and theoretical data.
The Thermal Expansion Behaviors of Cu-SiCp Composites
Authors: Azmi K. , Derman Mohd Nazree B. , Al Bakri Abdullah Mohd Mustafa
Published: September 2013

The demand for advanced thermal management materials such as silicon carbide reinforced copper matrix (Cu-SiCp) composites is increasing due to their high thermal conductivity and low CTE properties. However, the weak bonding between the copper matrix and the SiCp reinforcement degrades the thermophysical properties of the composites. In order to improve the bonding between the two constituents, the SiCp were copper coated (Cu-Coated) via electroless coating process. Based on the experimental results, the CTE values of the Cu-Coated Cu-SiCp composites were found significantly lower than those of the non-Coated Cu-SiCp composites. The CTEs of the Cu-Coated Cu-SiCp composites were in agreement with Kernels model which accounts for both the shear and isostatic stresses developed in the component phases.
The Influences of Cu-Coated SiCp on the Porosity and Thermal Expansion Behavior of Cu-SiCp Composites
Authors: Azmi K. , Tajuddin M.I.M. , Azida A.
Published: September 2013

The widespread use of metal matrix composites as the packaging materials is due to their tailorable thermal conductivity and coefficient of thermal expansion (CTE). For the same reason, silicon carbide reinforced copper matrix (Cu-SiCp) composites are highly rated as thermal management materials in the electronic packaging applications. However, the Cu-SiCp composites fabricated via the conventional powder metallurgy methods have inferior thermophysical properties due to the presence of porosity in the interface of copper matrix and the SiCp reinforcement. In order to improve the bonding between the two constituents, the SiCp were coated with copper via electroless coating process. Based on the experimental results, the CTE values of the copper coated Cu-SiCp composites were found significantly lower than those of the non-Coated Cu-SiCp composites. The CTEs of the composites tend to decrease as the porosity increases. The significant difference in the CTE values was related to the presence of sub-micron gap between the copper matrix and the SiCp reinforcement.
A Brief Review of Layered Rock Salt Cathode Materials for Lithium Ion Batteries
Authors: Tan T.Q. , Soo S.P. , Rahmat A. , Shamsul J.B. , Osman Rozana A.M. , Jamal Z. , Idris M.S.
Published: September 2013

Nowadays, many researchers have been studying on the layered rock salt-type structure as cathode materials for the lithium ion batteries. LiCoO2 is the most commonly used cathode material but Co is costly and toxic. Thus, alternative cathode materials which are cheaper, safer and having higher capacity are required. Replacing Co with Ni offered higher energy density battery but it raised interlayer mixing or cation disorder that impedes electrochemical properties of batteries. This paper has reviewed some recent research works that have been done to produce better and safer cathode materials from the structural perspective.