フレキシブルプリント配線板の耐折寿命に関する強度学的研究

概要

論文の詳細を見る
The mechanical reliability of flexible printed circuits, FPC was studied upon the basis of the conventional works on fatigue of structural materials. The lifetime of FPC, N_f was related to the maximum strain of copper Δε_<cu> as the straight relation of Δε_<cu>∝N_f^<-0.36> in the log-log diagram. It was found by experiment that the lifetime of FPC could be varied by controlling the tensile properties of adhesives and the thickness of copper foil, Kapton of the base material and adhesives. The lifetime, N_f could be improved by thinning the copper foil and adhesive and inversely by thickening Kapton of the base material. Also, there was an optimum rigidity-coefficient of the adhesive for the lifetime, N_f of FPC. During the lifetime of FPC, the fatigue process observed on copper foil could be divided into three stages as follows : the crack intiation, the crack density increase, the crack opening. The NG life of FPC, that is the electric resistance rising up to 10 % of the original value, was corresponded to stage of, the crack initation.
一般社団法人日本機械学会の論文
1991-02-25