(1. 江蘇大學(xué) 材料科學(xué)與工程學(xué)院，鎮(zhèn)江 212013;
2. 上海交通大學(xué) 密西根學(xué)院，上海 200240;
3. 江蘇理工學(xué)院 機(jī)械工程學(xué)院，常州 213000)
摘 要: 采用預(yù)固溶或預(yù)時(shí)效+LSP形變+后時(shí)效處理方法，研究預(yù)固溶或預(yù)時(shí)效以及后時(shí)效處理對(duì)激光沖擊AZ80鎂合金組織參數(shù)(孿晶和析出相)的影響。結(jié)果表明:預(yù)固溶+激光沖擊強(qiáng)化(LSP)形變處理使LSP強(qiáng)化層內(nèi)產(chǎn)生高密度孿晶的形變帶，離沖擊表面越近，孿晶密度越高;經(jīng)(170 ℃, 16 h)時(shí)效處理后，由于殘余壓應(yīng)力熱穩(wěn)定性，預(yù)固溶+LSP形變強(qiáng)化層仍產(chǎn)生具有高密度孿晶的形變帶;同時(shí)，彌散析出大量的顆粒狀β-Mg17Al12相，優(yōu)先在應(yīng)力集中的形變帶、孿晶界面和孿晶片層內(nèi)析出;預(yù)時(shí)效析出的高密度β相極大地降低沖擊強(qiáng)化層孿生產(chǎn)生率，孿晶體積分?jǐn)?shù)明顯降低，這是由于LSP誘導(dǎo)的高密度位錯(cuò)和析出相引起的。
關(guān)鍵字: AZ80鎂合金;激光沖擊強(qiáng)化;固溶;時(shí)效;孿晶;析出相
（1. School of Materials Science and Engineering, Jiangsu University, Zhenjiang 212013, China;
2. Joint Institute, University of Michigan- Shanghai Jiao Tong University, Shanghai 200240, China;
3. School of Mechanical Engineering, Jiangsu University of Technology, Changzhou 213000, China）
Abstract:The effect of pre-solution, pre-aging and post-aging on microstructure parameters (twins and precipitates) of laser shocked AZ80 magnesium alloy was investigated by pre-solution or pre-aging+LSP deformation+post-aging. The results show that the deformation band with high density twins in the strengthened layer is produced by the treatment of pre-solution+laser shock processing(LSP) deformation, and the twins density increases with decrease of the distance to the impacted surface. The deformation band with high density twins is still produced by treatment of aging treatment for 16 h under the temperature of 170 ℃ due to the stability of the residual compressive stresses. At the same time, a large number of granular β-Mg17Al12 phases are dispersively and preferentially precipitated in the deformation band, the twin interface and the twin lamellae where the stress concentration exists. The ratio of twinning in the strengthened layer is greatly reduced by the high density β phase precipitated from the pre-solution, and the volume fraction of the twins is decreased significantly, because of the high density dislocation and precipitates induced by LSP.
Key words: AZ80 magnesium alloy; laser shock processing; solution; aging; twins; precipitate
