(1. 上海交通大學(xué) 材料科學(xué)與工程學(xué)院，上海 200240；
2. 上海交通大學(xué) 機(jī)械與動(dòng)力工程學(xué)院，上海 200240；
3. 上海交通大學(xué) 輕合金精密成型國家工程研究中心，上海 200240；
4. 上海交通大學(xué) 金屬基復(fù)合材料國家重點(diǎn)實(shí)驗(yàn)室，上海 200240)
摘 要: 采用常規(guī)擠壓和等通道角擠壓工藝加工得到高強(qiáng)度Mg97Y2Zn1鎂合金。結(jié)果表明：常規(guī)擠壓后，鎂合金晶粒尺寸為0.5~2.0 μm，屈服強(qiáng)度、抗拉強(qiáng)度和伸長率分別達(dá)到352 MPa、413 MPa和10%。常規(guī)擠壓后再經(jīng)過等通道角擠壓，晶粒尺寸被進(jìn)一步細(xì)化到300~400 nm，屈服強(qiáng)度和抗拉強(qiáng)度進(jìn)一步提高到400 MPa和450 MPa。在鑄態(tài)、常規(guī)擠壓態(tài)和等通道角擠壓態(tài)的Mg97Y2Zn1合金中，都發(fā)現(xiàn)有長周期有序的精細(xì)層狀結(jié)構(gòu)存在，其產(chǎn)生與基體中溶有少量Y和Zn元素有關(guān)。晶粒細(xì)化和精細(xì)層狀結(jié)構(gòu)的存在是材料高強(qiáng)度的原因。
關(guān)鍵字: 鎂合金；Mg97Y2Zn1；等通道角擠壓；力學(xué)性能；高強(qiáng)度；長周期有序結(jié)構(gòu)
equal channel angular pressing
（1. School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China;
2. School of Mechanical and Power Engineering, Shanghai Jiao Tong University, Shanghai 200240, China;
3. National Engineering Research Center for Light Alloy Net Forming, Shanghai Jiao Tong University, Shanghai 200240, China;
4. National Key Laboratory of Metallic Matrix Composite Material, Shanghai Jiao Tong University, Shanghai 200240, China）
Abstract:The high strength Mg97Y2Zn1 alloy processed by extrusion and equal channel angular pressing was investigated. The results show that after extrusion, the processed Mg97Y2Zn1 alloy obtains ultrafine grains with average grain size of 0.5−2.0 μm, and exhibits excellent mechanical properties with yield strength, ultimate tensile strength and elongation of alloy of 352 MPa, 413 MPa and 10%, respectively. After extrusion and equal channel angular pressing, the average grain size is 300−400 nm, the yield strength and ultimate tensile strength of the alloy are 400 MPa and 450 MPa, respectively. The long-period stacking lamellar structure is observed in the as-cast, extruded and ECAP processed Mg97Y2Zn1 alloy, the formation of which is due to the solid solution of Y and Zn. The excellent mechanical properties of Mg97Y2Zn1 alloy are attributed to the grain refinement and the long-period stacking structure.
Key words: Magnesium alloy; Mg97Y2Zn1; equal channel angular pressing; mechanical properties; high strength; long-period stacking structure
