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401. Effects of Graphene Oxide Addition on Mechanical and Thermal Properties of Evoh Films

Author

González-Ruiz, Jesús, Yataco-Lazaro, Lourde, Virginio, Sueli, das Graças da Silva-Valenzuela, Maria, Moura, Esperidiana, Valenzuela-Díaz, Francisco, Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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402. Properties of Clay for Ceramics with Rock Waste for Production Structural Block by Pressing and Firing

Author

Cerqueira, N. A., Choe, D., Alexandre, J., Azevedo, A. R. G., Xavier, C. G., Souza, V. B., Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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403. Microstructure Analysis of Buildups Embedded in Carbon Sleeve in Continuous Annealing Furnace for Non-Oriented Silicon Steel

Author

He, Mingsheng, Xue, Gaifeng, Peng, Shoujun, Liu, Meng, Zhou, Wangzhi, Chen, Huasheng, Zhang, Jing, Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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404. Improvement of Mechanical Properties in Natural Rubber with Organic Fillers

Author

Gonzales-Fernandes, M., Bastos, Andrade C. G., Esper, F. J., Valenzuela-Diaz, F. R., Wiebeck, H., Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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405. Speciation and Characterization of E-Waste, Using Analytical Techniques

Author

López, C. Cortés, Cruz, V. E. Reyes, Rodríguez, M. A. Veloz, Ávila, J. Hernández, Badillo, J. Flores, Murcia, J. A. Cobos, Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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406. The Characterization of the Desulfurization Powder in the Semi-Dry DE-SO2 Process of the Sintering Plant Exhaust Gas and its Interaction with the Soil Particles

Author

Kang, Ling-Chen, Lu, Li-jun, Xue, Gai-feng, Hwang, Jiann-Yang, Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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407. Properties of Mortars with Partial and Total Replacement of Conventional Aggregate by Waste Construction

Author

Cerqueira, N. A., Choe, D., Alexandre, J., Azevedo, A. R. G., Xavier, C. G., Souza, V. B., Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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408. Effect of Magnesium Aluminate Spinel Content on Properties of BN Based Composites

Author

Liu, Meng, Song, Yijie, Xu, Xiaohong, Xu, Guotao, Xue, Gaifeng, Liu, Jixiong, Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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409. Characterization of Waste Molding Sands, for Their Possible Use as Building Material

Author

Mauricio, Guerrero R., Juan, Hernández A., Javier, Flores B., Eleazar, Salinas R., Isauro, Rivera L., V., Ma. Isabel Reyes, Eduardo, Cerecedo S., Víctor, E. Reyes C., Carmen, Cortés L., Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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410. Silver Cementation with Zinc From Residual X Ray Fixer, Experimental and Thermochemical Study

Author

Labra, M. Pérez, Pérez, M. Reyes, Serrano, J. A. Romero, Dávila, E. O. Ávila, Hernández, F. R. Barrientos, Thangarasu, Pandiyan, Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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411. Brillouin Scattering Spectroscopy on Mg-Nd Alloy in Different Aging Time

Author

He, Xinyi, Meng, Wenjian, Wu, Yongquan, Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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412. Effect of the Paper Industry Residue on Properties in the Fresh Mortar

Author

Azevedo, A. R. G., Alexandre, J., Vieira, C. M. F., Xavier, C. G., Zanelato, E. B., Oliveira, L. I. V., Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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413. Passive Films Formed on Stainless Steels in Phosphate Buffer Solution

Author

Méndez, Claudia Marcela, Burgos, Rodrigo Elvio, Bruera, Florencia, Ares, Alicia Esther, Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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414. Characterization of a Mineral of the District of Zimapan, Mina Concordia, Hidalgo, for the Viability of the Recovery of Tungsten

Author

Martín, Reyes P., Miguel, Perez L., Julio, Cesar Juárez T., Aislinn, Michelle Teja R., Francisco, Patiño C., Mizraim, Uriel Flores G., Iván, A. Reyes D., Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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415. Direct Synthesis of Carbon Nanotubes at Low Temperature by the Reaction of CCl4 and Ferrocene

Author

Luo, Wei, Tang, Yan, He, Mingsheng, Ouyang, Degang, Ding, Cuijiao, Han, Bin, Zhu, Shanhe, Li, Minghui, Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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416. Characterization of Incorporation the Glass Waste in Adhesive Mortar

Author

Santos, D. P., Azevedo, A. R. G., Hespanhol, R. L., Alexandre, J., Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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417. Preparation of Polymeric Phosphate Ferric Sulfate Flocculant and Application on Coking Wastewater Treatment

Author

Wang, Lina, Hwang, Jiannyang, Xue, Gaifeng, Zhang, Lei, Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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419. Recovery of Palladium and Aluminum from Spent Catalysts by Roasting-Leaching

Author

Li, Qian, Rao, Xuefei, Yang, Yongbin, Xu, Bin, Hu, Long, Jiang, Tao, Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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420. Effect of Phase Transformations on Hardness in Zn-Al-Cu Alloys

Author

Villegas-Cardenas, Jose D., Lopez-Hirata, Victor M., Saucedo-Muñoz, Maribel L., Gonzalez-Velazquez, Jorge L., Avila-Davila, Erika O., Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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421. Experimental Study of Advanced Treatment of Coking Wastewater Using MBR-RO Combined Process

Author

Zhang, Lei, Hwang, Jiannyang, Leng, Ting, Xue, Gaifeng, Chang, Hongbing, Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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422. Assimilation Reaction Characteristic Number for Evaluating the Assimilation of Iron Ore in Sintering

Author

Zhao, Yong, Wu, Keng, Du, Ruilmg, Shen, Wei, Du, Xiaodong, Zhu, Chunen, Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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424. Small Punch Creep Test in a 316 Austenitic Stainless Steel

Author

Saucedo-Muñoz, Maribel L., Komazaki, Ken-Icbi, Ortiz-Mariscal, Arturo, Lopez-Hirata, Victor M., Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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425. Effect of Microstructural Anisotropy on the Dynamic Mechanical Behaviour of Rolled Ti-6Al-4V

Author

Lock, A. C. H., Brown, A. D., Blessington, R. A., Appleby-Thomas, G., Quadir, Md. Z., Hazell, P. J., Escobedo, J. P., Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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427. Influence of Al and C on Mechanical Properties of Sub-Rapidly Solidified Fe-20Mn-xAl-yC Low-Density Steels

Author

Liu, Libing, Shen, Zhengyan, Yang, Yang, Song, Changjiang, Zhai, Qijie, Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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428. Resonances of Microwave Power Absorption in Alumina and Silicon Carbide

Author

Peng, Zhiwei, Lin, Xiaolong, Hwang, Jiann-Yang, Zhang, Yuzhe, Zhang, Yuanbo, Li, Guanghui, Jiang, Tao, Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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430. Physical and Chemical Properties of MSWI Fly ash

Author

Xinghua, He, Shujing, Zhu, Hwang, Jiann-Yang, Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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432. Microstructure Evolution during Thermal Aging of Inconel 718

Author

Devarapalli, R. S., Marin, E., Cormier, J., Le Gall, C., Franchet, J.-M., Jouiad, M., Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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433. An Empirical Equation to Predict the Porosity of Titanium Foams

Author

Jian, Xiao, Hao, Cui, Guibao, Qiu, Yang, Yang, Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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434. Determination of the Stability Constants of Mixed-Ligand Coordination Compounds in the Zn(II)-Nitrilotriacetic Acid-Ammonia System

Author

Chen, Lin, Hao, Zhandong, Yang, Tianzu, Zhang, Duchao, Liu, Weifeng, Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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435. Microstructure of Metal Injection Molded MIM418 Using Master Alloy Technique

Author

Zhang, Lin, Chen, Xiaowei, Chen, Chi, Qu, Xuanhui, Ikhmayies, Shadia Jamil, editor, Li, Bowen, editor, Carpenter, John S., editor, Hwang, Jiann-Yang, editor, Monteiro, Sergio Neves, editor, Li, Jian, editor, Firrao, Donato, editor, Zhang, Mingming, editor, Peng, Zhiwei, editor, Escobedo-Diaz, Juan P., editor, and Bai, Chenguang, editor

Published
2016
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437. Failure analysis of a crane gear shaft

Author

Darko Pastorčić, Goran Vukelić, Goran Vizentin, Iacoviello, Francesco, Susmel, Luca, Firrao, Donato, and Ferro, Giuseppe

Subjects
business.product_category, Materials science, Spiral bevel gear, business.industry, Drivetrain, Fracture mechanics, 02 engineering and technology, Structural engineering, 021001 nanoscience & nanotechnology, Spall, Finite element method, Stress (mechanics), 020303 mechanical engineering & transports, 0203 mechanical engineering, Fracture (geology), gear, bevel gear, crane gear shaft, failure analysis, 0210 nano-technology, business, Contact area, Earth-Surface Processes
Abstract

This research deals with a teeth failure of a gear shaft that served as a part of shipyard crane drive train. Almost all of the teeth of a spiral bevel gear, part of a larger shaft, fractured during normal operation of the crane. Failure analysis combined experimental and numerical research. Visual inspection was employed to determine the fracture location and crack propagation paths. Microscopy, optical and scanning electron (SEM), was used to inspect damaged surfaces of the teeth, reveal possible flaws and fine microstructure of the material. Type of steel used for manufacturing was determined based on chemical composition of the material obtained using optical emission spectrometer with glow discharge source (GDS) sample stimulation. Further, tensile specimens were extracted from the shaft to test the strength of the steel. Additionally, hardness test was performed. All experimental research suggest it is a case of gear teeth spalling, probably caused by excessive contact stresses. To gain better understanding of the failure process, a 3D numerical model of the gear shaft was built and finite element (FE) stress analysis performed. Analysis showed excessive contact stresses at the teeth contact area. Time-varying meshing stiffness (TVMS), an important gear health condition parameter, is determined via FE procedure for several examples of healthy to gradually damaged gear. Obtained results show how spall propagation influences TVMS and, thus, affects gear performance leading to potential failure.

Published
2019
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438. An improved Finite Fracture Mechanics approach to blunt V-notch brittle fracture mechanics: Experimental verification on ceramic, metallic, and plastic materials.

Author

Sapora, Alberto, Cornetti, Pietro, Carpinteri, Alberto, and Firrao, Donato

Subjects
*FRACTURE mechanics, *BRITTLE fractures, *EXPERIMENTAL design, *CERAMIC materials, *MECHANICAL loads
Abstract

The coupled Finite Fracture Mechanics (FFM) criterion is applied to investigate brittle fracture in rounded V-notched samples under mode I loading. The approach is based on the contemporaneous fulfilment of a stress requirement and the energy balance, the latter being implemented on the basis of a recently proposed analytical expression for the stress intensity factor. Results are presented in terms of the critical crack advance and the apparent generalized fracture toughness, i.e. the unknowns related to the system of two equations describing the FFM criterion. A validation of the theory is performed by employing varying root radius notched, as-quenched from 1200 °C, AISI 4340 steel specimens fracture results as well as alumina and PMMA notched samples fracture results. [ABSTRACT FROM AUTHOR]

Published
2015
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439. Three-Dimensional Heat Transfer Modeling of a Moving Plate in Forming Process Applications.

Author

Lavella, Mario, Maizza, Giovanni, Borgna, Massimo, Firrao, Donato, Ghosh, S., Castro, J.C., and Lee, J.K.

Subjects
*HEAT transfer, *PLATING, *FURNACES, *CHEMICAL engineering, *INDUSTRIAL chemistry, *MATERIALS science
Abstract

A three-dimensional heat transfer model of glass plates heating and cooling has been developed to study their thermal tempering. The furnace being modeled is of a tunnel type, in which the glass plate alternates translational motions with back and forth mouvements with a specified law. An appropriate implementation of a moving (transient) convection/radiation boundary condition has been proposed to describe the heat transfer exchanged between the glass surfaces and the furnace environment. The model results have been experimentally validated by a scanning pyrometer which detects the pointwise temperature of the upper surface of the plate at the exit of the furnace. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

Published
2004
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440. Fatigue Behavior of Dual-Phase and TWIP Steels for Lightweight Automotive Structures.

Author

Matteis, Paolo, Scavino, Giorgio, D'Aiuto, Fabio, and Firrao, Donato

Subjects
*FATIGUE (Physiology), *COLD rolling, *TENSILE strength, *MARTENSITE, *TWINNING (Crystallography), *FRACTURE mechanics, *WELDING
Abstract

Car bodies are increasingly made with high-strength steels, for both lightweighting and safety purposes. Steel sheets, made by continuous casting, hot rolling, cold rolling, and continuous heat treating, are used to deep draw the car body parts, which are then joined by resistance spot welding (RSW). Two high-strength automotive steels, with similar tensile strength, are studied here. The low alloy, dual-phase steel consist of ferrite and martensite, obtained by an intercritical heat treatment, followed by fast cooling. The innovative, high-Mn TWIP steel exhibits a promising combination of strength and toughness, arising from the austenitic structure, strengthened by C, and from the twinning induced plasticity effect. Tensile specimens are fatigue tested at room temperature with zero load ratio, both in the as-fabricated (unnotched) condition and after the RSW of an homologous sheet square. Moreover, pre-cracked compact tension specimens are tested with load ratio 0.1 to determine the fatigue crack growth behavior. These results are completed with crystallographic, microstructural, tensile, and fractographic examinations, and the influence of the microstructure and of the welding process is discussed. [ABSTRACT FROM AUTHOR]

Published
2012
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441. Friction and wear behaviour of sintered steels submitted to sliding and abrasion tests

Author

Ceschini, Lorella, Palombarini, Giuseppe, Sambogna, Giuliano, Firrao, Donato, Scavino, Giorgio, and Ubertalli, Graziano

Subjects
*SINTERING, *TRIBOLOGY, *SLIDING friction, *STEEL
Abstract

Abstract: Fe–C–Mo and Fe–C–Cr steels were sintered by PM processes carried out using different values of temperature and pressure, leading to different microstructures and density values. Flat specimens were submitted to tribological tests in order to evaluate their behaviour under both dry sliding and abrasive wear conditions. A flat-on-cylinder tribometer was used for the sliding tests, while a micro-scale ball cratering device was used for the abrasion tests. The dry sliding wear resistance of the PM steels was mainly influenced by the composition and sintering conditions. In this regard, the best behavior was observed for the more hardenable Fe–C–Mo steels with higher Mo content, sintered under conditions giving rise to bainitic microstructures. A determining role was also played by the porosity content and pore shape: reduction in porosity (obtained by increasing the sintering temperature and the compacting pressure), as well as an increase in pore roundness, led to a significant improvement in the resistance to sliding wear. A mild oxidative wear regime were observed for all the sintered steels under relatively low values of the applied load, while an increase of the applied load led to a delamination wear regime. The resistance to abrasive wear was low for all the tested steels, irrespective of composition and sintering cycle. [Copyright &y& Elsevier]

Published
2006
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442. Failure analysis of a motor vehicle coil spring

Author

Goran Vukelić, Marino Brčić, Iacoviello, Francesco, Susmel, Luca, Firrao, Donato, and Ferro, Giuseppe

Subjects
Engineering, business.industry, 020209 energy, coil spring, spring steel, failure analysis, 02 engineering and technology, Structural engineering, Microstructure, Coil spring, Finite element method, law.invention, Spring steel, 020303 mechanical engineering & transports, 0203 mechanical engineering, Optical microscope, Electromagnetic coil, law, Spring (device), 0202 electrical engineering, electronic engineering, information engineering, Fracture (geology), Composite material, business, Earth-Surface Processes
Abstract

Due to frequent failures of coil springs on a specific type of motor vehicle, analysis of possible causes of failures was performed. Analysis was done on a single coil spring removed from a vehicle after failing in service. Besides visual examination that revealed fracture to happen on a first bottom coil, several other experimental techniques were used in the failure analysis. Using optical microscopy evaluation of the basic microstructure of the fractured surface was performed and possible inclusions distinguished. Detailed scanning electron microscopy (SEM) examination at suitable magnifications was employed to characterize the fine microstructure of the fractured surface and reveal flaws that served as crack initiation points. Optical emission spectrometer with glow discharge source (GDS) sample stimulation was used to determine chemical composition of material used for spring fabrication. Additionally, hardness test was performed. Using results of the performed experimental analysis, possible causes of failure were recognized. Several factors, among them inherent material defect combined with material fatigue and helped by insufficient corrosion protection, caused failure of coil spring. Obtained results are valuable in predicting behaviour of coil springs mounted in other vehicles of the same type and can be taken as a reference in improving future design. Further analysis would include employing finite element method to determine stress levels in undamaged and damaged coil spring along with numerical estimation of fatigue life.

Published
2016
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443. Passive films formed on stainless steels in phosphate buffer solution

Author

Rodrigo Elvio Burgos, Alicia Esther Ares, Florencia Alejandra Bruera, Claudia Marcela Méndez, Ikhmayies, Shadia Jamil, Li, Bowen, Carpenter, John, Hwang, Jiann Yang, Monteiro, Sergio Neves, Li, Jian, Firrao, Donato, Zhang, Mingming, Peng, Zhiwei, and Bai, Chenguang

Subjects
Equiaxed crystals, Materials science, corrosion, Phosphate buffered saline, Metallurgy, stainless steels, 02 engineering and technology, INGENIERÍAS Y TECNOLOGÍAS, Intergranular corrosion, 010402 general chemistry, 021001 nanoscience & nanotechnology, Electrochemistry, Phosphate, 01 natural sciences, 0104 chemical sciences, Corrosion, chemistry.chemical_compound, chemistry, Ingeniería de los Materiales, impedance, 0210 nano-technology
Abstract

The behaviour of passive films formed on directionally solidified stainless steels,18Cr10Ni2Mo0.08C, 18Cr14Ni8Mo0.03C and 18Cr10Ni8Mo0.08C, in different areas that wereformed during solidification (columnar, columnar-to-equiaxed transition (CET) and equiaxed)was studied using electrochemical testing in Na2HPO4 with / without NaCl. The behavior ofstainless steel in the presence of phosphate chlorides is the best compared to non-chloridephosphate. Fil: Méndez, Marcela Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Burgos, Rodrigo Elvio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Bruera, Florencia Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Ares, Alicia Esther. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina

Published
2016
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444. Prediction the jominy curves by means of neural networks

Author

Filetin, Tomislav, Majetić, Dubravko, Žmak, Irena, Firrao, Donato, and Mittemeijer, J. Eric

Subjects
steels, jominy curve, prediction of properties, artificial neural network
Abstract

Accurate prediction of hardenability based on the chemical composition is very important for steel production as well as for its users. An attempt has bees made to establish a non-lionear static discrete-time neuron model, the so-called Static Elementary processor (SEP). Based on the SEP neurons, a Static Multy Layer Perceptron Neural Network is proposed to predict a Jominy hardness curve from chemical composition. To accelerate the convergence of proposed static error-back propagation learning method, the momentum method is applied. The learning results are presented in terms that are insensitive to learning data range and allow easy comparison with other learning algorithms, inedendent of machine architecture or simulator implementation. In the learning process datasets with 121 heats are used - comprising samples from 40 steel grades with different chemical composition. The mean error between measured nad predicted hardness data and standard deviation for testing dataset (60 heats - samples from 203 heats in question) is comparable with other published methods of prediction. The additional testing of three smaller groups - Cr- steels ; Cr-Ni-Mo (Ni-Cr-Mo) steels for hardening and tempering and Cr-Mo, Cr-Ni (Ni-Cr), Cr-Ni-Mo (Ni-Cr-Mo) steels for carburizing shows better accuracy then by testing with heterogeneous dataset.

Published
1998

445. An analysis of the production and applicability of austempered ductile iron and alloyed AS-CAST bainitic ductile iron

Author

Cajner, Franjo, Mrša, Josipa, Smoljan, Božo, Firrao, Donato, and Mittermeier, Eric J.

Subjects
ductile iron, mold-cooling, austempering, quench and tempering
Abstract

The productions of bainitic ductile iron by austempering heat treatment and byalloying during the casting were investigated. The process parameters of bainitic ductile iron production by the austempering heat treatment and by alloying were analyzed. According to recommended dimensions and geometrical shape of machine parts and required mechanical properties, the chemical composition and appropriate parameters of both processes were determined. A technological and economical comparasion of the production ability and applicability in machine building was done between austempered ductile iron and alloyed as-cast bainitic ductile iron. Limitations in application of both processes were done from comparsion of mechanical properties between machine parts processed by both processes. Realistic cost/benefit analysis and technological comparison between processes ability was done too.

Published
1998

446. Metal objects mapping after small charge explosions. A study on AISI 304Cu steel with two different grain sizes.

Author

Firrao D, Matteis P, Scavino G, Ubertalli G, Ienco MG, Pellati G, Piccardo P, Pinasco MR, Stagno E, Costanza G, Montanari R, Tata ME, Brandimarte G, and Petralia S

Abstract

Evidence of exposure of a metal component to a small charge explosion can be detected by observing microstructural modifications; they may be present even if the piece does not show noticeable overall plastic deformations. Particularly, if an austenitic stainless steel (or another metal having a face-centered cubic structure and a low stacking fault energy) is exposed to an explosive shock wave, high-speed deformation induces primarily mechanical twinning, whereas, in nonexplosive events, a lower velocity plastic deformation first induces slip. The occurrence of mechanical twins can be detected even if the surface is damaged or oxidized in successive events. In the present research, optical metallography (OM) and scanning electron microscopy (SEM), and scanning tunneling microscopy (STM) were used to detect microstructural modifications caused on AISI 304Cu steel disks by small-charge explosions. Spherical charges of 54.5 or 109 g TNT equivalent mass were used at explosive-to-target distances from 6.5 to 81.5 cm, achieving peak pressures from 160 to 0.5 MPa. Explosions induced limited or no macro-deformation. Two alloy grain sizes were tested. Surface OM and SEM evidenced partial surface melting, zones with recrystallization phenomena, and intense mechanical twinning, which was also detected by STM and X-ray diffraction. In the samples' interior, only twins were seen, up to some distance from the explosion impinged surface and again, at the shortest charge-to-sample distances, in a thin layer around the reflecting surface. For forensic science locating purposes after explosions, the maximum charge-to-target distance at which the phenomena disappear was singled out for each charge or grain size and related to the critical resolved shear stress for twinning.

Published
2006
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