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排序方式: 共有2168条查询结果,搜索用时 15 毫秒
1.
《Ceramics International》2022,48(2):1898-1907
AlN ceramic was successfully wetted and then joined with nonactive Sn9Zn eutectic solder assisted by ultrasonication in air. The effect of ultrasonic time on the formation of joint was studied. Results indicated that the defect-free joint can be obtained at an ultrasonic time of 5 s. Two regions, namely, AlN/Sn (s,_s) and AlN/Zn (s,_s), were found in the bonding interface. Zn and O accumulated in the AlN/Sn (s,_s) interface. An amorphous and nanocrystalline layer of ZnO formed in the hard-wet AlN surface. And Zn (s,_s) directly bonded with AlN. The low temperature and fast bonding of the AlN was attributed to the high pressure and temperature caused by cavitation effect. The shear strength of the joint increased from 10.6 MPa to 30.7 MPa when the ultrasonic treatment time increased from 5 s to 150 s. With the prolongation of ultrasonic time, more AlN ceramic particles entered the solder and acted as the reinforcing phase. 相似文献
3.
《中国有色金属学会会刊》2022,32(10):3312-3320
The effects of trace addition of Al2O3 nanoparticles (NPs) on thermal reliabilities of Sn-0.5Ag-0.7Cu/Cu solder joints were investigated. Experimental results showed that trace addition of Al2O3 NPs could increase the isotheraml aging (IA) and thermal cyclic (TC) lifetimes of Sn-0.5Ag-0.7Cu/Cu joint from 662 to 787 h, and from 1597 to 1824 cycles, respectively. Also, trace addition of Al2O3 NPs could slow down the shear force reduction of solder joint during thermal services, which was attributed to the pinning effect of Al2O3 NPs on hindering the growth of grains and interfacial intermetallic compounds (IMCs). Theoretically, the growth coefficients of interfacial IMCs in IA process were calculated to be decreased from 1.61×10-10 to 0.79×10-10 cm2/h in IA process, and from 0.92×10-10 to 0.53×10-10 cm2/h in TC process. This indicated that trace addition of Al2O3 NPs can improve both IA and TC reliabilities of Sn-0.5Ag- 0.7Cu/Cu joint, and a little more obvious in IA reliability. 相似文献
4.
Han Bit Lee Young Won Kim Sang Hoon Kim Suk Hee Park Joon‐Phil Choi Clodualdo Aranas Jr. 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(33)
A modular solder system with hierarchical morphology and micro/nanofeatures in which solder nanoparticles are distributed on the surface of template micropowders is reported. A core–shell structure of subsidiary nanostructures, which improved the intended properties of the modular solder is also presented. In addition, polymer additives can be used not only as an adhesive (like epoxy resin) but also to impart other functions. By combining all of these, it is determined that the modular solder system is able to increase reflowability on a heat‐sensitive plastic substrate, oxidation resistance, and electrical conductivity. In this respect, the system could be readily modified by changing the structure and composition of each constituent and adopting backward compatibility with which the knowledge and information attained from a previously designed solder can offer feedback toward further improving the properties of a newly designed one. In practice, In–Sn–Bi nanoparticles engineered on the surface of Sn–Zn micropowders result in pronounced reflowing on a flexible Au‐coated polyethylene terephthalate (PET) substrate even at the low temperature of 110 °C. Depending on their respective concentrations, the incorporation of CuO@CeO2 nanostructures and poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) polymers increases oxidation resistance and electrical conductivity of the modular solder. 相似文献
5.
M.A. Azmah Hanim C.K. Wei T.T. Dele-Afolabi O.S. Azlina 《Materialwissenschaft und Werkstofftechnik》2021,52(9):943-951
In this study, the mechanical performance of the rice husk ash-reinforced tin-0.7 copper composite solder was investigated. 0.01 wt.%, 0.05 wt.% and 0.1 wt.% of rice husk ash (RHA) were added to the solder matrix to prepare the composite solders. In order, to replace the costly electroless nickel immersion gold surface finish on the copper substrate, the effect of electroless nickel immersion silver (ENIAg) as the surface finish was studied. The differential scanning calorimetry (DSC) analysis showed that the composite solder exhibited lower melting temperature relative to the plain solder owing to the inclusion of rice husk ash. Shear strength analysis was carried out to investigate the influence of rice husk ash and electroless nickel immersion silver surface finish on the shear strength of the developed composite solders. The results proved that the rice husk ash failed to enhance the shear strength of tin-0.7 copper lead-free solder with the plain solder exhibiting the highest shear strength. 相似文献
6.
无铅BGA封装可靠性的力学试验与分析 总被引:4,自引:0,他引:4
着重研究了机械冲击和应力对无铅BGA封装焊点可靠性的影响,介绍了BGA封装的可靠性力学试验(跌落、弯曲试验)及其分析方法.通过对力学试验中失效焊点的分析以及借助ANSYS模拟工具,找出引起失效的根本原因,为开发性能更好、高可靠性的无铅材料、改进无铅工艺提供依据. 相似文献
7.
BGA焊点的质量控制 总被引:1,自引:0,他引:1
BGA是现代组装技术的新概念,它的出现促进SMT(表面贴装技术)与SMD(表面贴装元器件)的发展和革新,并将成为高密度、高性能、多功能及高I/O数封装的最佳选择.本文结合实际工作中的一些体会和经验,就BGA焊点的接收标准、缺陷表现及可靠性等问题展开论述,特别对有争议的一种缺陷空洞进行较为详细透彻的分析,并提出一些改善BGA焊点质量的工艺改进的建议. 相似文献
8.
对冶金建筑总院1982年、1993年两次16Mn系列钢疲劳试验研究报告进行了对比分析,利用试验数据研究了原试验目的之外的课题:不同韧性钢材开孔应力集中、不同韧性焊材、K型对接焊缝焊趾角α、拉伸试件带肋断弧及弯曲试件K型对接焊缝对疲劳强度的影响,并对后三个课题提出了修正补充和建议,还对吊车梁焊透的T形焊缝焊角尺寸t_w/2降至t_w/4可行性试验结果进行了解释.本文可供《钢结构设计规范》(GBJ17—88)修订时参考. 相似文献
9.
总结了大同北岳联合厂房焊接球节点网架安装施工经验,详细介绍了焊接球网架安装方法,指出利用拼装单元网格作为滑移平台,高空散装法安装网架结构可以解决吊车无法吊装到位的困难,且又节省拼装费用,对类似工程具有一定的指导作用。 相似文献
10.