電子連接器高分子材料結構失效評估

Abstract

高分子材料取代金屬材料作為結構件時，常因其機械性質相對較差而導致結構件失效。本研究擬檢視廣泛應用於電子產品之液晶高分子(liquid crystalline polymer, LCP)承受負載之斷裂行為。執行單軸拉伸與壓縮實驗，獲致其承受負載至斷裂之行為。採用有限元素分析，搭配適合描述高分子材料組成律，自行撰寫使用者副程式VUMAT，預測高分子材料承受負載之形變與斷裂行為。材料參數係利用一維組成律，配合單軸壓縮工程應力-應變量測結果進行曲線擬合獲得，接續將取得之材料參數導入三維組成律，再次與單軸壓縮力量-位移量測結果進行校調與驗證。施加負載於電子連接器高分子結構件進行裂痕評估，藉以提供產品設計改良之依據。

Stiffness often becomes an issue when metallic materials are replaced with engineering plastics for the use of structural components. Fracture behaviors of the Liquid Crystalline Polymer (LCP) which have been widely adopted in electronic products are investigated in the current study. Finite element analysis is carried out in conjunction with a self-coded user subroutine VUMAT accounting for the mechanical response of the plastic materials. Various parameters required for a constitutive model with rate-dependency are first evaluated using experiments for a plastic sample subjected to the uniaxial compression condition. Failure assessments of a plastic housing of a memory connector under application conditions are conducted, and the simulated crack appearing in the housing matches rather well with the corresponding experimental observation.