underfill crack 中文意思是什麼
underfill crack
解釋
底部填充裂縫-
The stress intensity factor ( sif ) and the strain energy release rate were simulated with different pre - crack length for the cases with no - flow underfill and with capillary - flow underfill
本文第六章用斷裂力學方涪和有限元模擬分析了填充不流動膠晶元斷裂問題，計算了晶元的應力強度因於k和能量釋放率g 。 -
Zhang liji ( material physics and chemistry ) directed by professor xie xiaoming this paper is intended to solve problems for those who are designing, using pbgas. failure mechanism, as well as cycles to failure of two groups of pbga samples ( with / without underfill ) for thermal cycling conditions in the range of - 40 ~ 125, were presented. the experiment shows that solder ball in the samples without underfill cracked after 500 times cycle, no crack was found in the underfilled samples even after 2700 cycles
通過一系列的實驗，得到以下實驗結果： ?在本論文設定的溫度循環條件下，未充膠pbga樣品的熱疲勞品壽命在500周左右，充膠樣品的焊點壽命高於2700周； ?對于未充膠器件，中心距（ dnp ）是決定焊點應力、應變大小的最主要因素，裂紋總是從中心距較大處萌生並向中心處擴展； ?溫度循環的過程中焊盤附近焊料組織明顯粗化。
分享友人