Volume 2: Materials; Joint MSEC-NAMRC-Manufacturing USA最新文献_第5页

Understanding Mechanical Integrity of Metal/Ceramic Interfaces Through In-Situ Micro Mechanical Testing and Multiscale Simulations 通过原位微力学测试和多尺度模拟了解金属/陶瓷界面的力学完整性

Volume 2: Materials; Joint MSEC-NAMRC-Manufacturing USA Pub Date : 2018-06-18 DOI: 10.1115/MSEC2018-6471

Xiaoman Zhang, Y. Mu, S. Shao, C. Wick, R. Ramachandran, W. Meng

{"title":"Understanding Mechanical Integrity of Metal/Ceramic Interfaces Through In-Situ Micro Mechanical Testing and Multiscale Simulations","authors":"Xiaoman Zhang, Y. Mu, S. Shao, C. Wick, R. Ramachandran, W. Meng","doi":"10.1115/MSEC2018-6471","DOIUrl":"https://doi.org/10.1115/MSEC2018-6471","url":null,"abstract":"Mechanical failures of interfacial regions of ceramic-coating/metal-adhesion-layer/substrate systems were measured quantitatively and observed concurrently through instrumented microscale mechanical testing in-situ a scanning electron microscope (SEM). Failure of the interfacial regions of coating/interlayer/substrate systems was observed in micro-pillar specimens in-situ under different loading conditions, including shear, compression, and tension.\u0000 Under shear loading, shear failure of the interfacial region was observed to occur in two stages: an initial uniform shear plastic deformation of the entire metal interlayer followed by an unstable shear-off close to the metal/ceramic interface. Additional testing under compression loading conditions suggests that the unstable shear-off is concomitant with the metal/ceramic interface going from being “locked”, with no relative displacement between materials on the two sides of the interface, to being “unlocked”, with significant relative displacements. Failure of the interfacial region was also observed under tensile loading conditions.\u0000 Density functional theory (DFT) and molecular dynamics (MD) studies on one particular metal/ceramic interface, namely Ti/TiN, showed that a weak interaction plane exists in the metal layer near the chemical interface in a coherent Ti/TiN structure. Consequently, the free energy and theoretical shear strength of the semi-coherent Ti/TiN interface is found to depend on the physical location of the misfit dislocation network (MDN). The minimum energy and strength of the interface occur when the MDN is near, but not at the chemical interface. The present work gives new insight into the nature of mechanical failure of metal/ceramic interfaces, is relevant to materials-based engineering of metal/ceramic interfaces, and has applications to engineering of ceramic coating/substrate systems.","PeriodicalId":290562,"journal":{"name":"Volume 2: Materials; Joint MSEC-NAMRC-Manufacturing USA","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122389780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Interlaminar Toughening of Fiber Reinforced Polymers by Synergistic Modification of Resin and Fiber 树脂与纤维协同改性纤维增强聚合物的层间增韧

Volume 2: Materials; Joint MSEC-NAMRC-Manufacturing USA Pub Date : 2018-06-18 DOI: 10.1115/MSEC2018-6528

Dakai Bian, Jason C. Tsui, R. Kydd, D. Shim, Marshall G. Jones, Y. Yao

{"title":"Interlaminar Toughening of Fiber Reinforced Polymers by Synergistic Modification of Resin and Fiber","authors":"Dakai Bian, Jason C. Tsui, R. Kydd, D. Shim, Marshall G. Jones, Y. Yao","doi":"10.1115/MSEC2018-6528","DOIUrl":"https://doi.org/10.1115/MSEC2018-6528","url":null,"abstract":"The synergistic effect of combining different modification methods was investigated in this study to improve the interlaminar toughness and delamination resistance of fiber reinforced polymers (FRP). Epoxy-compatible polysulfone (PSU) was end-capped with epoxide group through functionalization, and the fiber surface was chemically grafted with amino functional group to form a micron-size rough surface. Consequently, the long chain of PSU entangles into crosslinked thermoset epoxy network, additionally, epoxide group on PSU further improves the bonding through chemical connection to the epoxy network and amino group on fiber surface. The combined modification methods can generate both strong physical and chemical bonding. The feasibility of using this method in vacuum assisted resin transfer molding was determined by rheometer. The impact of formed chemical bonds on the crosslinking density was examined through glass transition temperatures. The chemical modifications were characterized by Raman Spectroscopy to determine the chemical structures. Synergistic effect of the modification was established by Mode I and Mode II fracture tests which quantify the improvement on composites delamination resistance and toughness. The mechanism of synergy was explained based on the fracture mode and interaction between the modification methods. Finally, Numerical simulation was used to compare samples with and without modifications. The experiment results showed that synergy is achieved at low concentration of modified PSU because the formed chemical bonds compensate the effect of low crosslinking density and interact with the modified fiber.","PeriodicalId":290562,"journal":{"name":"Volume 2: Materials; Joint MSEC-NAMRC-Manufacturing USA","volume":"33 1-2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116725549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Machining Performance and Microstructure Evolution in Milling Advanced Low-Alloy Military-Grade Steel 铣削高级低合金军用钢时的加工性能和显微组织演变

Volume 2: Materials; Joint MSEC-NAMRC-Manufacturing USA Pub Date : 2018-06-18 DOI: 10.1115/MSEC2018-6566

J. Wolf, C. Saldana, Tom Maloney, John P. Quitter, John Von Roemer

{"title":"Machining Performance and Microstructure Evolution in Milling Advanced Low-Alloy Military-Grade Steel","authors":"J. Wolf, C. Saldana, Tom Maloney, John P. Quitter, John Von Roemer","doi":"10.1115/MSEC2018-6566","DOIUrl":"https://doi.org/10.1115/MSEC2018-6566","url":null,"abstract":"Next generation defense applications for structural steels require new alloys that eliminate or reduce critical materials from their composition, while maintaining or exceeding the high strength and toughness requirements for extreme shock or dynamic loading environments. A new alloy system has been developed for this purpose and characteristics of its manufacture and material response in component manufacturing must be understood. In the present study, the relative machinability of a new structural steel, denoted as AF9628, was evaluated relative to a surrogate steel benchmark (AISI4340). The effects of machining parameters employed in milling across a range of machining speeds, feed rates and cooling conditions was investigated by measurements of force signatures and surface roughness. Machined chips were collected and measured to determine the relative effects of these parameters on evolved microstructure. Changes in chip hardness and microstructure were observed due to the effect of cooling conditions in the milling process. Subsurface microstructure was measured using electron backscatter diffraction. The utility of these methods for understanding machinability for defense alloys and components is briefly discussed.","PeriodicalId":290562,"journal":{"name":"Volume 2: Materials; Joint MSEC-NAMRC-Manufacturing USA","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128553483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Spectroscopic Studies of Dissimilar Al-Cu Laser Welding 异种铝铜激光焊接的光谱研究

Volume 2: Materials; Joint MSEC-NAMRC-Manufacturing USA Pub Date : 2018-06-18 DOI: 10.1115/MSEC2018-6310

P. Schmalen, P. Plapper

引用次数: 5

Mechanical Behavior of LDPE/MWCNT Composites After Fatigue and Cryogenic Treatment 低温疲劳处理后LDPE/MWCNT复合材料的力学行为

Volume 2: Materials; Joint MSEC-NAMRC-Manufacturing USA Pub Date : 2018-06-18 DOI: 10.1115/MSEC2018-6532

C. Fetecau, F. Stan, Petru Timotin, NICOLETA-VIOLETA Stanciu, R. Roșculeț

引用次数: 0

A Study of Friction Stir Welding of High Density Polyethylene 高密度聚乙烯搅拌摩擦焊的研究

Volume 2: Materials; Joint MSEC-NAMRC-Manufacturing USA Pub Date : 2018-06-18 DOI: 10.1115/MSEC2018-6318

J. Sheikh-Ahmad, Dima S. Ali, F. Jarrar, S. Deveci

引用次数: 5

The Microstructural Origin of Sinuous Flow in Metal Cutting 金属切削中弯曲流动的微观组织成因

Volume 2: Materials; Joint MSEC-NAMRC-Manufacturing USA Pub Date : 2018-06-18 DOI: 10.1115/MSEC2018-6342

Vandana A. Salilkumar, Narayan K. Sundaram

引用次数: 1

Supercritical CO2 Pretreatment of Cellulosic Biomass for Biofuel Production: Effects of Biomass Particle Size 用于生物燃料生产的纤维素生物质的超临界CO2预处理:生物质粒度的影响

Volume 2: Materials; Joint MSEC-NAMRC-Manufacturing USA Pub Date : 2018-06-18 DOI: 10.1115/MSEC2018-6656

Yang Yang, T. W. Deines, Meng Zhang, Ke Zhang, Donghai Wang

{"title":"Supercritical CO2 Pretreatment of Cellulosic Biomass for Biofuel Production: Effects of Biomass Particle Size","authors":"Yang Yang, T. W. Deines, Meng Zhang, Ke Zhang, Donghai Wang","doi":"10.1115/MSEC2018-6656","DOIUrl":"https://doi.org/10.1115/MSEC2018-6656","url":null,"abstract":"Biofuel derived from cellulosic biomass is a sustainable alternative to petroleum-based fuel. Pretreatment is an essential step in biofuel production because it accounts for more than 20% of the inputs. Furthermore, particle size reduction as a preprocessing step prior to pretreatment exerts a substantial impact on all following processes. Many studies have investigated the effects of biomass particle size on sugar yield after conventional pretreatments of biomass such as alkaline and dilute acid pretreatments. The similar trends have shown that smaller biomass particle size results in higher sugar yield. Supercritical CO2 (SC-CO2) pretreatment has been applied at 1450 psi, 120 °C for 30 mins in this study as a pretreatment method for biofuel production from cellulosic biomass. As a recyclable green-chemistry method, SC-CO2 pretreatment offers many advantages such as no toxic chemicals added and low-cost input. The objective of this study is to understand the effects of particle size on sugar yield after SC-CO2 pretreatment. Three particle size: 1 mm, 2 mm, and 4 mm were used for size reduction of corn stover. Ethanol and water were used as co-solvents to enhance SC-CO2 pretreatment. Analysis of variance (ANOVA) was performed and it is found that, after SC-CO2 pretreatment, the sugar yields differ significantly between 1 mm and 2 mm, 1 mm and 4 mm. In contrast, there is no significant difference between 2 mm and 4 mm after SC-CO2 pretreatment. 1 mm particle produced the highest sugar yield of 0.115 g glucose per 1 g of dry biomass which is 16.62% and 10.39% higher than the 4 mm and 2 mm corn stover biomass produced.","PeriodicalId":290562,"journal":{"name":"Volume 2: Materials; Joint MSEC-NAMRC-Manufacturing USA","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114229015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4