(重慶大學(xué) 機(jī)械傳動(dòng)國(guó)家重點(diǎn)實(shí)驗(yàn)室，重慶 400044)
摘 要: 基于實(shí)驗(yàn)及Shiratori的有限元數(shù)據(jù)，擬合出鋁合金板淬火殘余應(yīng)力的分布函數(shù)，用Shen-Glinka法確定橢圓裂紋的Ⅰ型應(yīng)力強(qiáng)度因子的權(quán)函數(shù)，推導(dǎo)出權(quán)函數(shù)系數(shù)的表達(dá)式。在此基礎(chǔ)上分析幾種裂紋表面經(jīng)典應(yīng)力分布時(shí)的Ⅰ型應(yīng)力強(qiáng)度因子，與Shiratori的有限元結(jié)果吻合良好，驗(yàn)證所建立的權(quán)函數(shù)具有較高的精度。結(jié)合淬火殘余應(yīng)力分布函數(shù)，推導(dǎo)出橢圓裂紋在淬火殘余應(yīng)力場(chǎng)中的Ⅰ型應(yīng)力強(qiáng)度因子，得出不同點(diǎn)殘余應(yīng)力強(qiáng)度因子隨裂紋擴(kuò)展的變化趨勢(shì)不同。
關(guān)鍵字: 鋁合金；淬火殘余應(yīng)力；橢圓裂紋；應(yīng)力強(qiáng)度因子；權(quán)函數(shù)
（State Key Laboratory of Mechanical Transmission, Chongqing University, Chongqing 400044, China）
Abstract:Based on the experiments and Shiratori’s finite element data, the distribution functions of quenching residual stress in aluminum alloy plates were fitted, the weight functions of elliptical crack were derived by Shen-Glinka’s method. The weight functions were verified using available finite element results for basic mode of residual stress fields and good agreement is achieved, which approves that the weight functions appear to be particularly suitable for residual stress fields. Combined with the quenching residual stress distribution function, the mode I stress intensity factors of elliptical cracks in residual stress field were calculated using the weight functions, and the trends of residual stress intensity factor with crack propagation at different points are different.
Key words: aluminum alloy; quenching residual stress; elliptical crack; stress intensity factor; weight function
