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素的分布. 所用焊料合金列于表1. 表1 研究所用焊料合金性能 Table 1 Properties of solder alloys investigated 2 实验结果 2.1 焊点的微观结构 回流焊后空冷试样经50℃退火24h以消除残余应力[3]. 图1(a)~(c)所示分别为Sn-9Zn, Sn-8Zn-3Bi...) and Sn-7Zn-0.03Al(c) alloys 表2 Sn-Zn基焊点的疲劳寿命 Table 2 Fatigue lifetime for Sn-Zn system solder joints 图2 Sn-8Zn-3Bi焊点试样经120℃, 100%相对湿度高压釜中时效并经LCF的失效组织 Fig.2  ......
(Ⅱ): Sustained-load crack growth in dry air at 50-200℃[J]. Mater Sci Eng A, 1991, 36: 45-57. [2]Pitcher P D, Stewart R T, Gupta S. Study of reversion behaviour in 8090 alloys using small angle neutron... stability of 2090 Al-Cu-Li alloys[J]. Materials Science Forum, 1996, 217-222(2): 1079-1084. [4]Lumley R N, Morton A J, Polmear I J. Enhanced creep performance in an Al-Cu-Mg-Ag alloy through underageing[J......
and the recrystallized grain size of alloys basically tends to be stable. 4 AZ61 microstructure evolutions at different deformation rates 4.1 Microtexture of AZ61 Texture and grain orientation of AZ61... mechanisms[6]. Studies[7-11] have shown that a strong basal texture (0001) is formed as a result of basal slip and pyramidal twinning in magnesium alloys during rolling. Fig.6(a) is characterized......
;Chemical compositions of alloys(mole fraction, %) 图1 合金经1150℃, 72h, AC均匀化处理后的组织 Fig.1 Microstructures of alloys homogenized at 1150℃ for 72h 图2 合金A和B的近γ组织经不同温度固溶处理后的组织 Fig.2 Microstructures of alloys after near gamma microstructures solution treated at different temperatures 所有固溶处理后的试样随后均进行了900℃, 6h, 炉冷(FC)的时效处理. 对经4种热处理制度处理后的合金A和B试样进行了760℃, 275MPa条件下的持久性......
, SZ-2Cu, 对应着L→Sn+Zn+Cu5Zn8反应, Cu含量6%时对应着近共晶反[CM(22]应, 而Cu含量为8%时对应着L→Sn+CuSn+Cu6Sn5近共晶反应. 除了SZ-4Cu外, 所有的合金融化区间都比较小, 这对形成好的接头组织是有利的. 图4 SZ-xCu钎料X射线衍射谱 Fig.4 XRD patterns of SZ-xCu solder alloys 2.3... profile of Sn-Zn-Cu solder alloys 图6所示为钎料与Cu箔钎焊润湿角随Cu含量的变化曲线. 从图6中可以看出: Cu元素的添加能够有效提高合金的润湿性. 当Cu含量小于2%时, 钎料润湿角呈直线下降, 随着Cu含量的不断增加, 钎料的润湿角逐渐减小, 最终由120°下降为54°左右. 由图7可知, 平衡状态时的润湿角是由界面表面张力决定的......
A. Property Mea-surements on Osprey Spray-Deposited Al-Si Alloys[R]. ERBFMGECT980141, Neath, SAII INJ, UK: Aerospace and Space Materials Technology Testhouse, 2002. [2] 廖恒成, 孙国雄. 铸造Al-Si合金中Sr与B的交互作用[J]. 中国有色金属学报, 2003, 13(2): 353-359. LIAO Heng-cheng, SUN Guo-xiong. Interaction between Sr and B in Al-Si casting alloys[J]. The Chinese Journal of Nonferrous Metals, 2003, 13(2): 353-359. [3] 张金山, 许春香, 韩富银......
alloys(SMAs) have attracted considerable attention for their novel performances, such as shape memory effect(SME), pseudoelasticity, high damping[1]. From the late 1980s, the recovery stress...]. Recently, extensive researches have been devoted to the constrained martensitic transformation of shape memory alloys. Some investigations confirmed that partial transformation cycle could affect......
alloys formed by the interalloying/interdiffusion[6]. It is thought that these localized adhesions may also be formed by forge welding(seizing) at the contacting surfaces under high pressure although... and to alloying[6]. The precipitation strengthened Cu-Cr, Cu-Cr-Zr and Cu-Zr alloys were most commonly used electrode materials for resistance spot welding of coated steels. There has been, however, a continuous......
; Document code: A 1 INTRODUCTION Recently, the use of magnesium alloys as structural materials has significantly increased, for its good damping capacity, dimension stability, machinability and low casting costs. But magnesium alloys normally exhibit low ductility near room temperature because of their HCP structure. Therefore, it is necessary to improve......
to a low specific strength (strength to density). The key to making strong but light self-lubricating materials is to find an appropriate metal as the backing of polymer composites. Aluminum alloys...). Al-Zn-Mg alloys are heat-treatable strengthening alloys, cold-rolled plates need solid solution and aging treatment. After 465℃/40min solution treatment, water quenching and 120℃/24h aging, samples......