bluuebunny/crossref_metadata_2025_split huggingface dataset:
Failure Analysis of a Vehicle Engine Crankshaft
Authors: Alfares M. A. , Falah A. H. , Elkholy A. H. 
Published: January 2020

Abstract
An investigation of a damaged crankshaft from a horizontal, six-cylinder, in-line diesel engine of a public bus was conducted after several failure cases were reported by the bus company. All crankshafts were made from forged and nitrided steel. Each crankshaft was sent for grinding, after a life of approximately 300,000 km of service, as requested by the engine manufacturer. After grinding and assembling in the engine, some crankshafts lasted barely 15,000 km before serious fractures took place. Few other crankshafts demonstrated higher lives. Several vital components were damaged as a result of crankshaft failures. It was then decided to send the crankshafts for laboratory investigation to determine the cause of failure. The depth of the nitrided layer near fracture locations in the crankshaft, particularly at the fillet region where cracks were initiated, was determined by scanning electron microscope (SEM) equipped with electron-dispersive X-ray analysis (EDAX). Microhardness gradient through the nitrided layer close to fracture, surface hardness, and macrohardness at the journals were all measured. Fractographic analysis indicated that fatigue was the dominant mechanism of failure of the crankshaft. The partial absence of the nitrided layer in the fillet region, due to over-grinding, caused a decrease in the fatigue strength which, in turn, led to crack initiation and propagation, and eventually premature fracture. Signs of crankshaft misalignment during installation were also suspected as a possible cause of failure. In order to prevent fillet fatigue failure, final grinding should be done carefully and the grinding amount must be controlled to avoid substantial removal of the nitrided layer. Crankshaft alignment during assembly and proper bearing selection should be done carefully.
Stress Corrosion Cracking of Ring Type Joint of Reactor Pipeline of a Hydrocracker Unit
Authors: Gore Poorwa , Sujata M. , Bhaumik S.K. 
Published: January 2020

Abstract
A ring-type joint in a reactor pipeline for a hydrocracker unit had failed. Cracks were observed on the flange and the associated ring gasket during an inspection following a periodic shutdown of the unit. The components were manufactured from stabilized grades of austenitic stainless steel; the flange from type 321, and the ring gasket from 347. Examination revealed that the failure occurred by transgranular stress-corrosion cracking, initiated by the presence of polythionic acid. Detailed metallurgical investigation was subsequently conducted to identify what may have caused the formation of polythionic acid in the process gas.
Stress-Corrosion Cracking of a Monel 400 Tube
Authors: Katsamas A.I. , Haidemenopoulos G.N. , Zervak A.D. , Melas I. 
Published: January 2020

Abstract
A bent Ni-Cu Monel 400 alloy tube, which operated as part of a pipeline in a petrochemical distillery, failed by through-thickness cracking. The pipeline was used to carry a stream of gaseous hydrocarbons containing hydrochloric acid (HCl) into a reaction tower. The tower provided a caustic solution (NaOH) to remove HCl from the stream, before the latter was directed to a burner. Metallographic examination showed that the cracks were intergranular and were frequently branched. Although nominal chemical composition of the component was found within the specified range, energy dispersive x-ray analysis (EDXA) indicated significant segregation of sulfur and chlorine along the grain boundaries. Failure was attributed to hypochlorous-acid (HClO)-induced stress-corrosion cracking (SCC). The HClO was formed by the reaction of HCl with atmospheric O2 that entered the tube during shutdowns and startups. Residual stresses, originating from in situ bend forming of the tube during assembly of the line, provided a driving force for crack growth, and the segregation of sulfur on grain boundaries made the material more susceptible to cracking.
Failure Analysis of a Fractured Wrench Socket
Authors: Nasrazadani S. , White P. 
Published: January 2020

Abstract
A 13/16-in. hex socket failed while in use. Analysis (hardness testing, optical and scanning electron microscopy, and EDS) revealed that the socket was made of low carbon steel formed in a powder metallurgy process. A number of flaws were found including nonuniform wall thickness, poor geometric design with sharp corners as stress raisers, and incomplete sintering evidenced by unsintered particles. These were determined to be the primary cause of failure, although inclusions on the fracture surface containing S and Al may have played a role as well.
Fatigue Failure of a Drive Shaft
Authors: Banuta Marina , Tarquini Isabelle 
Published: January 2020

Abstract
The drive shaft in a marine propulsion system broke, stranding a large vessel along the Canadian seacoast. The shaft was made from quenched and tempered low-alloy steel. Fractographic investigation revealed that the shaft failed under low rotating-bending variable stress. Fatigue propagation occurred on about 95% of the total cross section of the shaft, under both low-cycle and high-cycle fatigue mechanisms. It was found that the fillet radius at the fracture’s origin was smaller than the one provisioned by design. As a result, the stresses at this location exceeded the values used in the design calculations, thus causing the initiation of the cracking. Moreover, although the shaft had been quenched and tempered, its actual hardness did not have the optimal value for long-term fatigue strength.
Failure Analysis of Epoxy Resin Encapsulant During a Long-Term Storage
Authors: Zhang Guobin , Wang Yusen , Zhang Shinian , Liu Chunhe 
Published: January 2020

Abstract
The crosslinked epoxy resin encapsulant protecting an electromagnetic valve coil failed during long-term storage and was examined to determine the cause. The investigation included fault-tree analysis, FTIR and EDX spectroscopy, and differential scanning calorimetry with thermogravimetric analysis. Based on test data, the epoxy resin had not been properly cured and was hydrolyzed in its compromised state because of humidity. Hence, the depolymerized material gradually softened to the point where the effect of creep caused it to flow, ultimately causing the failure.
Microscopic Analysis of Fractured Screws Used as Implants in Bone Fixation
Authors: Barbosa Cassio , de Cerqueira Abud Ibrahim , Barros Tatiana Silva , de Carvalho Sheyla Santana , Caminha Ieda Maria Vieira 
Published: January 2020

Abstract
A stainless steel screw securing an orthopedic implant fractured and was analyzed to determine the cause. Investigators used optical and scanning electron microscopy to examine the fracture surfaces and the microstructure of the austenitic stainless steel from which the screw was made. The results of the study indicated that the screw failed due to fatigue fracture stemming from surface cracks generated by stress concentration likely caused by grooves left by improper machining.
Failure Analysis of Torsion Bar of Projectile Weaving Machine
Authors: Sekercioglu Tezcan 
Published: January 2020

Abstract
Several torsion bars had failed in a projectile weaving machine and were analyzed to determine the cause. Specimens prepared from the damaged components were subjected to visual inspection, hardness testing, chemical analysis, and metallurgical evaluations. The failed torsion bars had been fabricated from spring steel which, according to stress calculations, did not have sufficient torsional strength. Examination of the damaged parts confirmed the finding, revealing that all fractures started at a shoulder radius in an area of high stress concentration. Based on the investigation, the shoulder radius should be increased to alleviate stress and the working torsion angle of the bar should be decreased to improve safety factors.
Corrosion Failures in Gas Turbine Hot Components
Authors: Kosieniak E. , Biesiada K. , Kaczorowski J. , Innocenti M. 
Published: January 2020

Abstract
Gas turbines and other types of combustion turbomachinery are susceptible to hot corrosion at elevated temperatures. Two such cases resulting in the failure of a gas turbine component were investigated to learn more about the hot corrosion process and the underlying failure mechanisms. Each component was analyzed using optical and scanning electron microscopy, energy dispersive spectroscopy, mechanical testing, and nondestructive techniques. The results of the investigation provide insights on the influence of temperature, composition, and microstructure and the contributing effects of high-temperature oxidation on the hot corrosion process. Preventative measures are also discussed.
Failure Analysis of a Gas Turbine Marriage Bolt
Authors: Mohammadi Mohsen , Salimi Hamid Reza 
Published: January 2020

Abstract
An 18-MW gas turbine exploded unexpectedly after three hours of normal operation. The catastrophic failure caused extensive damage to the rotor, casing, and nearly all turbo-compressor components. Based on their initial review, investigators believed that the failure originated at the interface between two shaft sections held together by 24 marriage bolts. Visual and SEM examination of several bolts revealed extensive deterioration of the coating layer and the presence of deep corrosion pits. It was also learned that the bolts were nearing the end of their operating life, suggesting that the effects of fatigue-assisted corrosion had advanced to the point where one of the bolts fractured and broke free. The inertial unbalance produced excessive vibration, subjecting the remaining bolts to overload failure.
Failure Analysis of Fatigue Fracture on the Outer Ring of a Cylindrical Roller Bearing in an Air Blower Motor
Authors: Yu Zhi-Qiang , Yang Zhen-Guo 
Published: January 2020

Abstract
An air blower in an electric power plant failed unexpectedly when a roller bearing in the drive motor fractured along its outer ring. Both rings, as well as the 18 rolling elements, were made from GCr15 bearing steel. The bearing also included a machined brass (MA/C3) cage and was packed with molybdenum disulfide (MoS2) lithium grease. Metallurgical structures and chemical compositions of the bearing’s matrix materials were inspected using a microscope and photoelectric direct reading spectrometer. SEM/EDS was used to examine the local morphology and composition of fracture and contact surfaces. Chemical and thermal properties of the bearing grease were also examined. The investigation revealed that the failure was caused by wear due to dry friction and impact, both of which worsened as a result of high-temperature degradation of the bearing grease. Fatigue cracks initiated in the corners of the outer ring and grew large enough for a fracture to occur.
Failure Analysis of High-Level Radioactive Waste Tank Purge
Authors: Subramanian K.H. , Jenkins C.F. 
Published: January 2020

Abstract
High-level radioactive wastes generated during the processing of nuclear materials are kept in large underground storage tanks made of low-carbon steel. The wastes consist primarily of concentrated solutions of sodium nitrate and sodium hydroxide. Each of the tanks is equipped with a purge ventilation system designed to continuously remove hydrogen gas and vapors without letting radionuclides escape. Several intergranular cracks were discovered in the vent pipe of one such system. The pipe, made of galvanized steel sheet, connects to an exhaust fan downstream of high-efficiency particulate air filters. The failure analysis investigation concluded that nitrate-induced stress-corrosion cracking was the cause of the failure.
Failure Investigation of the Wind Turbine Blade Root Bolt
Authors: Liu Donghuan , Shang Xinchun 
Published: January 2020

Abstract
Wind turbine blades are secured by a number of high-strength bolts. The failure of one such bolt, which caused a turbine blade to detach, was investigated to determine why it fractured. Based on the results of a detailed analysis, consisting of stress calculations, chemical composition testing, metallurgical examination, mechanical property testing, and fractographic analysis, it was determined that the bolt failed by fatigue accelerated by stress concentration at low temperatures. The investigation also provided suggestions for avoiding similar failures.
Metallurgical Investigation into the Incidence of Delayed Catastrophic Cracking in Low Nickel Austenitic Stainless Steel Coils
Authors: Srikanth S. , Mousavi S.A.A. Akbari , Sisodia S. , Ravi K. 
Published: January 2020

Abstract
Several stainless steel coils cracked during a routine unwinding procedure, prompting an investigation to determine the cause. The analysis included optical and scanning electron microscopy, energy-dispersive x-ray spectrometry, and tensile testing. An examination of the fracture surfaces revealed a brittle intercrystalline mode of fracture with typical manifestations of clear grain facets. Branched and discrete stepwise microcracks were also found along with unusually high levels of residual hydrogen. Mechanical tests revealed a marked loss of tensile ductility in the defective steel with elongations barely approaching 8%, compared to 50% at the time of delivery weeks earlier. Based on the timing interval and the fact that failure occurred at operating stresses well below the yield point of the material, the failure is being attributed to hydrogen-induced damage. Potential sources of hydrogen are considered as are remedial measures for controlling hydrogen content in steels.
Fatigue of Electroformed Nickel
Authors: Jahed H. , Noban M. 
Published: January 2020

Abstract
A 2–3 mm thick electroformed nickel mold showed early cracking under thermal load cycles. To determine the root cause, investigators obtained monotonic and cyclic properties of electroformed nickel at various temperatures and identified possible fatigue mechanisms. With the help of finite element modeling, they analyzed the material as well as the design and in-service application of the mold. They discovered that overconstraining the mold, while it was in service, caused excessive thermal stresses which accelerated crack initiation and propagation. Investigators also proposed remedies to prevent additional failures.
Pour quel impact œuvrent les revues académiques ?
Authors: Dubost Nathalie , Kalika Michel 
Published: January 2020

En tant que parties prenantes aux communs de la connaissance, les revues académiques mettent en place des règles de production du savoir qui vont délimiter l’usage des connaissances, et donc leur impact. L’objectif de cet article1 est triple : explorer la vision qu’ont les revues de l’usage des connaissances qu’elles contribuent à produire, mettre en évidence les tensions éventuelles qu’elles rencontrent pour donner corps à cette vision de l’impact, et décrire les réponses apportées pour y remédier. Après avoir présenté les résultats d’une étude exploratoire exhaustive auprès des rédacteurs en chef de 15 revues francophones de la catégorie gestion du classement Fnege, les auteurs reviennent sur les apports théoriques et managériaux et proposent des pistes de recherche.
Régulation hybride dans les chaînes de valeur globales
Authors: Bastianutti Julie , Beierlein Laurence , Delalieux Guillaume 
Published: January 2020

Comment les dispositifs de contrôle des conditions de travail des sous-traitants des FMN s’adaptent-ils aux pressions divergentes des différents acteurs au sein des chaînes globales de valeur ? L’analyse de la genèse du programme pilote de l’OIT Better Factories Cambodia (BFC) montre comment un dispositif de régulation hybride s’est progressivement transformé et a contribué à l’émergence d’un programme global d’audit social (Better Work). L’étude revient sur les conditions d’une possible troisième voie dépassant l’opposition entre régulation publique et privée et souligne l’intérêt des analyses contextualisées et politiques des régimes de régulation socio-environnementale.
Microsurgical removal of a misplaced intraspinal venous stent in a patient with inferior vena cava atresia
Authors: Schwartz Christoph , Hafez Ahmad , Lönnrot Kimmo , Rezai Jahromi Behnam , Lappalainen Kimmo , Lehecka Martin , Siironen Jari , Niemelä Mika 
Published: January 2020

Inferior vena cava atresia (IVCA) is a rare vascular condition that may be treated by venous stenting. The authors report on the microsurgical removal of an intraspinally misplaced stent causing nerve root compression and neurological deficits.A 42-year-old patient with IVCA and painful cutaneous collaterals had been scheduled for treatment by stenting of the iliocaval confluence and associated venous collaterals. Initial stenting of the right iliac vein was successful; however, during recanalization of the left paravertebral plexus, the stent entered the spinal canal via extraspinal-to-intraspinal venous collaterals. Because of the use of monoplanar angiography, the stent misplacement was not seen during the procedure. Postinterventionally, the patient experienced a foot elevation weakness (grade 1/5) as well as pain and hypesthesia corresponding to the L5 dermatome. Ultrasonography ruled out a lumbosacral plexus hematoma. CT angiography showed that a stent had entered the spinal canal through the left S1 neuroforamen causing nerve root compression. The intraspinal portion of the stent was removed piecemeal via a left-sided hemilaminectomy. Venous bleeding due to the patient’s anticoagulation therapy, the stent’s sharp mesh wire architecture, and the proximity to nerve roots complicated the surgery. Postoperatively, the foot elevation improved to grade 4/5.
EFEKTIFITAS TEKNIK GAMBAR PERINGATAN BAHAYA MEROKOK DAN PENDIDIKAN NORMA SUBJEKTIF DENGAN INTENSI BERHENTI MEROKOK
Authors: Hamdani  , Herdianti  
Published: January 2020

Organisasi Kesehatan Dunia (WHO) menyatakan, tembakau membunuh lebih dari 5 juta orang per tahun, dan diproyeksikan akan membunuh 10 juta sampai tahun 2020. Intensi berhenti merokok dipengaruhi oleh norma subyektif dan gambar peringatan bahaya merokok. Untuk Provinsi Jambi jumlah perokok adalah sebanyak 22,9%. Adapun tujuan penelitian ini adalah untuk mengetahui pengaruh gambar peringatan bahaya merokok dan norma subyektif dengan intensi berhenti merokok mahasiswa STITEKNAS Jambi. Penelitian ini merupakan penelitian kuantitatif dengan desain Cross Sectional. Populasi adalah seluruh mahasiswa Stiteknas Kota Jambi yang merokok berjumlah 226 orang. Sampel diambil dengan teknik Accidental Sampling berjumlah 76 orang. Hasil penelitian diketahui intensi berhenti merokok kurang baik 40 (52,6%), gambar peringatan bahaya merokok kurang baik 37 (48,7%) dan norma subjektif kurang baik 34 (44,7%). Terdapat pengaruh antara gambar peringatan bahaya merokok dengan intensi berhenti merokok (r = 0,361 p value = 0,032). Tidak terdapat pengaruh antara norma subjektif dengan intensi berhenti merokok (r = 0,278 p value = 0,117). Berdasarkan hasil penelitian dan pembahasan dapat disimpulkan bahwa ada pengaruh gambar peringatan bahaya merokok dengan intensi berhenti merokok dan tidak ada pengaruh norma subyektif dengan intensi berhenti merokok mahasiswa STITEKNAS Jambi.
Kata Kunci : Intensi Berhenti Merokok, Gambar Peringatan Bahaya Merokok, Norma subjektif
HUBUNGAN PENGGUNAAN GIGI TIRUAN PENUH DENGAN STATUS GIZI PADA LANSIA DI DESA TONRONG RIJANG KECAMATAN BARANTI KABUPATEN SIDRAP
Authors: Rusnaeni Rusnaeni , Muhammad Azikin  , Fitriani Umar  
Published: January 2020

Salah satu perubahan secara biologis dapat mempengaruhi status gizi pada masa tua yaitu banyaknya gigi geligi yang sudah tanggal. Mengakibatkan gangguan fungsi mengunyah yang berdampak pada kurangnya asupan gizi pada usia lanjut, untuk memperbaiki mastikasi pengunyahaan maka lansia kebanyakn menggunaka gigi tiruan penuh. Penelitian ini bertujuan untuk mengetahui hubungan penggunaan gigi tiruan penuh dengan status gizi pada lansia di Desa Tonrong Rijang Kecamatan Baranti Kabupaten Sidrap.Jenis penelitian ini observasional analitik dengan rancangan cross sectional study. Populasi yaitu seluruh lansia yang tinggal menetap di Desa Tonrong Rijang, Pengambilan sampel dengan metode purposive sampling sebanyak 54 orang diperoleh dengan menggunakan rumus Slovin. Analisis data dengan menggunakan uji chi-square dan fisher exact test. dan ditolak jika nilai p< 0,05.Hasil penelitian diperoleh tidak ada hubungan penggunaan gigi tiruan penuh dengan asupan energi (p = 0,133) dan status gizi (p = 0,05), Serta ada hubungan signifikan asupan energi dengan status gizi (p = 0,000). Diharapkan kepada lansia untuk terus mempertahakan asupan energinya guna menigkatkan status gizi lansia untuk menunjang masa tuanya untuk hidup secara mandiri baik itu pengguna gigi tiruan penuh maupun yang tidak.
UJI KANDUNGAN LOGAM BERAT TIMBAL (Pb) DI PERAIRAN WILAYAH PESISIR PAREPARE
Authors: Ramlia Ramlia , Rahmi  , Abidin Djalla  
Published: January 2020

Perairan Parepare merupakan kawasan andalan yang sejauh ini berperan dan berfungsi sebagai pusat pelayanan jasa pelabuhan. Aktivitas pelabuhan dapat menjadi salah satu sumber pencemaran logam berat. Adanya logam berat di perairan sangat berbahaya baik secara langsung terhadap kehidupan organisme, ataupun terhadap kesehatan manusia. Salah satu pencemaran logam berat yang berbahaya bagi kesehatan manusia adalah timbal, karena bersifat toksis yang dapat menimbulkan efek kesehatan seperti gangguan sistem reproduksi, sistem syaraf, jantung dan ginjal. Penelitian ini bertujuan untuk menganalisis pencemaran logam berat timbal di perairan wilayah pesisir Parepare. Metode yang digunakan dalam penelitian ini adalah metode deskriptif dengan pendekatan Cross Sectional. Peneliti mengidentifikasi melalui observasional dan dengan melakukan uji laboraturium, sampel dalam penelitian ini sebanyak 5 lokasi . Data dianalisis secara deskriptif dengan membandingkan dengan standar baku mutu air laut dalam bentuk tabel atau grafik. Hasil penelitian menunjukkan terjadi pencemaran logam berat timbal di perairan wilayah pesisir Parepare pada 5 lokasi pengambilan sampel, dimana pada Lumpue di peroleh nilai (0,66 mg/L), Sumpang minangae (0,34 mg/L), Mattirotasi (0,70 mg/L), pelabuhan Nusantara (0,56 mg/L), dan Lakessi diperoleh nilai (0,58 mg/L). Hal ini telah melebihi standar baku mutu air laut, sehingga pemerintah perlu melakukan pengawasan terhadap kebersihan pesisir secara berkala dan melakukan penanaman vegetasi magrove.
BIOKONTROL IKAN PEMANGSA JENTIK DALAM PEMBERANTASAN VEKTOR NYAMUK PENYEBAB DEMAM BERDARAH DANGUE (DBD) di KOTA PAREPARE
Authors: Rahmi Rahmi , Rahmi Amir  , Usman  
Published: January 2020

Demam Berdarah Dengue (DBD) merupakan penyakit yang disebabkan oleh virus dan ditularkan oleh nyamuk Aedes aegypti yang masih menjadi masalah kesehatan masyarakat di Indonesia. Penyakit ini menyerang semua kelompok umur dan muncul setiap tahun. Pengendalian DBD dilakukan dengan memanfaatkan ikan predator jentik seperti ikan cupang (Betta spp). Tujuan penelitian adalah untuk mengetahui perbedaan memangsa dari ikan cupang (betta spp) berdasarkan variasi ukuran panjang badan dalam memangsa jentik nyamuk Aedes aegypti. Jenis penelitian ini adalah eksperimental semu dengan desain Rancangan Acak Lengkap (RAL) menggunakan uji Anova. Sampel adalah ikan cupang (Betta spp) dengan kelompok ukuran S (2,5-3,4 cm), M (3,5-5 cm) dan L (5,5 cm keatas). Hasil penelitian, menunjukkan ikan cupang ukuran L paling efektif dalam memangsa jentik dengan rata-rata memangsa 48,78 ekor dalam 15 menit dari pada ikan cupang ukuran S dengan rata-rata memangsa 36,50 ekor dalam 15 menit dan ikan cupang ukran M rata-rata memangsa 44,78 ekor dalam 15 menit. Hasil analisis menunjukkan ada perbedaan memangsa dari ikan cupang berdasarkan variasi ukuran panjang badan dengan (p=0,00). Disarankan untuk penanggulangan nyamuk Aedes aegypti dapat dilakukan dengan cara biologi yaitu dengan memanfaatkan ikan pemangsa jentik seperti ikan Betta spp.