(1. 上海交通大學(xué) 輕合金精密成型國(guó)家工程研究中心，上海 200030；
2. 上海交通大學(xué) 金屬基復(fù)合材料國(guó)家重點(diǎn)實(shí)驗(yàn)室，上海 200030)
摘 要: 針對(duì)月球環(huán)境溫度變化情形，研究了長(zhǎng)時(shí)間低溫浸泡(−196 ℃)和多次高低溫交變循環(huán)處理(−196~200 ℃)對(duì)擠壓態(tài)AZ31鎂合金在20 ℃下的力學(xué)性能、顯微組織以及斷口形貌的影響。研究表明：AZ31鎂合金經(jīng)過長(zhǎng)時(shí)間液氮浸泡和高低溫交變循環(huán)處理后，力學(xué)性能無明顯變化；室溫態(tài)合金的σb和δ分別為288 MPa和18.3%，經(jīng)過10 d低溫浸泡后σb和δ分別為292 MPa和18.7%，經(jīng)過10次高低溫循環(huán)后合金的σb和δ分別為294 MPa和16.9%；低溫和高低溫交變處理對(duì)斷口形貌和相組成沒有明顯影響，均為準(zhǔn)解理斷裂。
關(guān)鍵字: AZ31鎂合金；月球環(huán)境溫度；力學(xué)性能；微觀組織
AZ31 magnesium alloy after high and low temperature treatment
（1. National Engineering Research Center of Light Alloy Net Forming, Shanghai Jiao Tong University,
Shanghai 200240, China;
2. State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, China）
Abstract:In view of the lunar environment temperature change situation, the influence of long time low temperature immersion (−196 ℃) and high-low temperature alternation processing (−196−200 ℃) on the mechanical properties, microstructures and fracture surfaces of AZ31 magnesium alloy at 20 ℃ was studied. The results indicate that there are no significant changes on the mechanical properties of AZ31 magnesium alloy after liquid nitrogen immersion or temperature alternation cycle treatment. The σb and δ of AZ31 magnesium alloy at room temperature are 288 MPa and 18.3%, respectively, after 10 d cryogenic processing, they will reach 292 MPa and 18.7%, respectively. σb and δ after 10 times high-low temperature alternation processing are 294 MPa and 16.9%, individually. SEM observation and XRD results show that the fracture surface and phase constitutions do not change obviously after low temperature or high-low temperature alternation processing. And the fractures are both quasi-cleavage crack.
Key words: AZ31 magnesium alloy; lunar environment temperature; mechanical properties; microstructures
