【摘 要】
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This paper deals with a study on SnPb and lead-free soldered joint reliability of PLCC devices with different lead counts under three kinds of temperature cycle
【机 构】
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College of Materials Science and Technology
论文部分内容阅读
This paper deals with a study on SnPb and lead-free soldered joint reliability of PLCC devices with different lead counts under three kinds of temperature cycle profiles, which is based on non-linear finite element method. By analyzing the stress of soldered joints, it is found that the largest stress is at the area between the soldered joints and the leads, and analysis results indicate that the von Mises stress at the location slightly increases with the increase of lead counts. For PLCC with 84 leads the soldered joints was modeled for three typical loading (273-398 K, 218-398 K and 198-398 K) in order to study the influence of acceleration factors on the reliability of soldered joints. And the estimation of equivalent plastic strain of three different lead-free solder alloys (Sn3.8Ag0.7Cu, Sn3.5Ag and Sn37Pb) was also carried out.
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