C. Q. Wang
,
X. J. Zha
,
C. Q. Zhang
,
S. Q. Yang
,
C. Z. Wang( 1)National Lab of Advanced Welding Technology
,
HIT
,
Harbin 150001
,
China 2)Shanghai Institute of Metallurgy
,
Chinese Academy of Science
,
Shanghai 200050
,
China)
金属学报(英文版)
Solder joint reliability is one of critical problems detemining whether Sirface Mount Technology (SMT) can be used in the prohotion of important electronic products. Optimizing solder joint shape is one of effective ways to improve SMT solder joint reliability.In this paper. based on the theorem of minimum potential energy, an energy model of 3 - D solder joint shape is established,and the forma- tion of solder joint is numerically simulated by Surface Ecolver program. On the basis of the prediction of SMT solder joint shape,the mechanical model of analyzing solder joint reliability is established. An elasto - plasto - creep mateial model and its mechanical constitutive equaton are established for SnPb solder alloy, and the stress/strain response of SMT solder joint under thermal cyclical loabing is ana- lyzed with nonlinear 3 - D FEM. The fatigue life of solder joint is predicted according to Coffin- Manson fatigue life model. An integrated system for Predicting and analyzing SMT solder joint shape and reliability(PSAR) is developed.The system can analyze efficiently SMT solder joint reliability with the variation of structural parameters in the joint and give the optimal structure.
关键词:
SMT
,
null
,
null
,
null
卢维奇
,
李琼芳
功能材料
试制了Sn-2.5Ag-0.7Cu-0.5Sb免清洗焊膏,结果表明免清洗焊膏的印刷性能良好,触变性好,不会塌陷,有良好的焊接性.用免清洗焊膏焊接的软线路板FPCB清洁度高,且分别通过了BTH、HTSL和LTSL各1000h和热循环冲击1000次的苛刻条件的可靠性实验,证明了所试制的无铅免清洗焊膏的质量优良.
关键词:
免清洗焊膏
,
Sn-Ag系列焊膏
,
无铅化
,
SMT
赵麦群
,
于喜良
,
张卫华
,
赵高扬
材料导报
无铅焊锡微粉是一种可以满足SMT应用要求的环保材料.粉末的制备方法很多,但主要有4种,即化学还原法、电解法、机构粉碎法和雾化法等.通过对4种方法的对比可以知道,超音速气体雾化法制得的微粉粒度、颗粒形状和均匀性均能满足SMT的要求,所以可以应用超音速气体雾化法制备无铅焊锡微粉.
关键词:
无铅焊锡微粉
,
SMT
,
超音速气体雾化法
林健
,
雷永平
,
吴中伟
,
杨硕
稀有金属材料与工程
采用实验测试与数值模拟相结合的方法对锡铅钎料和无铅钎料SAC305板级焊点分别在热疲劳和机械疲劳载荷作用下的破坏规律进行比较研究.结果表明:相对于传统锡铅钎料而言,常用无铅钎料(SAC305)焊点结构具有较为优异的抗热疲劳性能,然而其抗机械疲劳性能相对较差.由此,采用有限元方法分析了两种钎料焊点结构在热疲劳和机械疲劳过程中的塑性应变和蠕变应变演变过程,以探讨表面贴装板级焊点结构热疲劳和机械疲劳破坏过程的本质区别.
关键词:
表面贴装结构
,
板级焊点
,
热疲劳
,
机械疲劳
,
非弹性应变
