文章信息/Info

Title:

 Experimental Measurement of Surface Residual Stresses of Quenched Aluminum Alloy Thick��

作者:

 胡永會; 吳運(yùn)新; 陳磊; 郭俊康

 （中南大學(xué)機(jī)電工程學(xué)院，湖南 長沙 410083）

Author(s):

HU Yonghui; WU Yunxin; CHEN Lei; GUO Junkang��

 (College of Mechanical and Electrical Engineering,Central South University,Changsha 410083，China)

關(guān)鍵詞:

 ; X射線衍射法; 7075鋁合金; 殘余應(yīng)力; 中心鉆孔法; 邊緣效應(yīng)

文獻(xiàn)標(biāo)志碼:

A

摘要:

    采用無損X射線衍射技術(shù)測試了7075鋁合金厚板淬火后表面殘余應(yīng)力水平與分布，得到了淬火鋁合金厚板表面殘余應(yīng)力的分布區(qū)間和一般規(guī)律，分析了準(zhǔn)直管對測試結(jié)果的影響，并與中心鉆孔法得到的結(jié)果做了比較。結(jié)果表明，兩種方法都能有效并正確測量構(gòu)件的表面殘余應(yīng)力，但中心鉆孔法不適合用于應(yīng)力梯度大的場合，而X射線法在無應(yīng)力或原始應(yīng)力水平很低的場合效果欠佳。淬火鋁板表面殘余應(yīng)力的測試結(jié)果呈正態(tài)分布，且淬火過程中邊緣局部有應(yīng)力釋放，釋放值可達(dá)40%，且此區(qū)域大小約為鋁板的一個(gè)厚度。��

Abstract:

    Surface residual stress distributions and general rules of quenched 7075 aluminum alloy thick plates were acquired by non�瞕estructive X ray diffraction method,in which effects of collimators were analyzed and the stress results were co MPared with measurements from center drilling method.The results show that both of the two surface stress measurement methods are effective and correct.But center drilling method is not suitable to conditions with large stress gradient while X ray method is not effective in conditions where there is no stress or very low initial stress level.In addition,surface residual stress measurements of the plates showing normal distributions which indicate credibility and correctness of the measured stress distributions.Edge effect causes residual stress relaxation near the edges of plates during quenching process,in which the maximum relaxation may amount to 40% of initial stress and the region size occurring stress relaxation would be equal to the thickness of the quenched plate.��