退火温度对等通道转角挤压态铁基形状记忆合金力学性能的影响  

Effects of Annealing Temperature on Mechanical Properties of Fe-Mn-Si Shape Memory Alloy Fabricated by Equal Channel Angular Pressing(ECAP)

作　　者：张伟[1] 李宁[1] 文玉华[1] 黄姝珂[1] 王志广[1] 

机构地区：[1]四川大学制造科学与工程学院,四川成都610065

出　　处：《金属热处理》2006年第10期58-61,共4页Heat Treatment of Metals

基　　金：国家自然科学基金项目(50501015);高等学校博士学科点专项科研基金项目(20030610093)

摘　　要：研究了退火温度对等通道转角挤压（ECAP）Fe17．80Mn4．73Si7．80Cr4．12Ni合金力学性能及显微组织的影响。结果表明，等通道挤压工艺能显著提高合金的屈服强度和抗拉强度，两道次挤压后合金的屈服强度达到880MPa，比固溶态高660MPa。退火温度从300℃升高到600℃时，合金屈服强度和抗拉强度降低，伸长率升高。挤压后经700℃×30rain退火后，材料的伸长率达到40％，屈服强度达到426MPa，再结晶基本完成，晶粒尺寸仅为0．3～2．5μm。细晶强化是该合金强度和伸长率提高的主要原因。Effects of annealing temperature on mechanical properties and microstructure of Fe,17.80Mn4. 73Si7.80Cr4. 12Ni alloy fabricated by equal channel angular pressing （ECAP） were studied. The results show that the yield strength and tensile strength of the alloy are remarkably improved by ECAP. The yield strength after two passes of the pressing reaches 880 MPa,which is 660 MPa higher than that of the as-solid solution alloy. With annealing temperature increasing from 300 ℃ to 600 ℃ , the yield strength and tensile strength decrease and the elongation increases. When annealed at 700 ℃.for 30 rain after ECAP processing, the elongation reaches 40% and the yield strength 426 MPa. Then the recrystallization j is completed and the grain size is only 0. 3 - 2.5 μm. Fine grain strengthening is the main factor for the improvement of strength and elongation.

关 键 词：等通道转角挤压 形状记忆合金 退火温度 力学性能 晶粒细化 

分 类 号：TG174.44[金属学及工艺—金属表面处理]