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℃ on the microstructural characteristics and microhardness of the Sn-6.5Zn solder/Cu joint was studied. The mechanisms for the formation and evolution of intermetallic compound (IMC) at the interface of the Sn-6.5Zn...: Sn-6.5Zn solder; interface; intermetallic compound; aging; evolution 1 Introduction Recently, as an important research interest of the newly functional materials, lead-free solders have been investigated......
Fig.13 Relationship between mean area of voids and void content in CFRP 图14 层中孔隙面积的频率分布直方图和概率密度曲线 Fig.14 Statistics histogram and probability density curves of mean areas for intra-laminate voids 图15 孔隙长宽比与孔隙率的关系 Fig.15 Relationship between aspect radio of voids and void content in CFRP 图15所示为孔隙长宽比随孔隙率的变化趋势,采样点由B样条曲线连接,阴影区域标识长宽比的取值范围.对比2种材料中层间孔隙长宽比的最大值,单向带和织物层间孔隙长宽比大于4的分界点分别为pv>1.0%和pv>......
Simulation for microstructure evolution of Al-Si alloys in solidification process XU Hong(徐 宏), HOU Hua(侯 华), ZHANG Guo-wei(张国伟) School of Materials Science and Engineering, North University of China, Taiyuan 030051, China Received 10 April 2006; accepted 25 April 2006 Abstract: The numerical simulation for microstructure evolution of Al-Si alloy in solidification process is carried out......
Microstructure evolution of semi-solid 2024 alloy during two-step reheating process WANG Shun-cheng(王顺成), LI Yuan-yuan(李元元), CHEN Wei-ping(陈维平), ZHENG Xiao-ping(郑小平) School of Mechanical...-liquid zone temperature. Microstructure evolution of the semi-solid billet during two-step reheating was studied by optical microscope and compared with that during isothermal reheating. The results show......
Microstructural evolution of aluminum alloy 3003 during annealing WU Wen-xiang(吴文祥)1, ZHANG Xin-ming(张新明)2, SUN De-qin(孙德勤)1, HU Guo-qiang(胡国强)1, LIU Guo-jin(刘国金)1 1. Suzhou Institute... 2006 Abstract: The microstructural evolution of cold-rolled aluminum alloy 3003 during annealing was investigated by means of micro-hardness measurement, electrical resistivity measurement, optical......
Microstructure evolution of aluminum-lithium alloy 2195 undergoing commercial production JIANG Na(蒋 呐)1, 2, GAO Xiang(高 翔)3, ZHENG Zi-qiao(郑子樵)1 1. School of Materials Science and Engineering... exist in all product states, which indicates that intermediate heat treatments have little influence on this iron-caused, detrimental phase. The formation and evolution of microstructures for different......
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distribution by height. Water content increases in frozen soil area, and decreases in unfrozen area. Wherever the ice lens body exists, void ratio tends to increase and water content increases substantially...; void ratio; mathematical model 中国的多年冻土面积占国土面积的22.3%,分布较广.冻土区的冻融作用使得构筑物出现裂缝,倾斜,沉陷,结构断裂等现象,给道路和构筑物造成很大的危害.冻土冻胀的机理研究一直是冻土界注重的问题之一[1-3].Harlan[4]根据未冻水动力学原理,提出考虑水分迁移和冰水相变的一维非线性水热耦合方程.该方程可用来求解温度和水分的变化.Konrad......
复合材料孔隙含量超声检测系统的设计研究 吴作伦1,宋立军2,蒋志峰1,吴瑞明1 (1.浙江科技学院机械与汽车工程学院,杭州,310023;2.北方设计研究院,石家庄,050011;3.浙江省计量科学研究院,杭州,310013) 摘要:本文结合碳纤维复合材料内部孔隙含量的超声检测理论模型,阐述了计算机控制超声检测系统数据采集和数据处理的原理和实施方法.重点对数字超声卡的操作,时域波形信号的处理,复合材料孔隙率的C扫描成像显示以及直方图分析等关键问题进行分析研究,开发相应的软件应用模块,构建合适的自动化超声检测系统,以满足实际工程中超声检测的要求. 关键词:超声检测; 孔隙率; 复合材料; ultrasonic test; void content; CFRP; [全文内容正在添加中] ......