(1. 河南理工大學(xué) 材料科學(xué)與工程學(xué)院，焦作 454000；
2. 河南理工大學(xué) 經(jīng)濟管理學(xué)院，焦作 454000)
摘 要: 對鑄態(tài)Mg-6.0%Zn-1.0%Y-0.6%Ce-0.6%Zr合金采用往復(fù)擠壓和正擠壓相結(jié)合的工藝，制備了d 1.55~2.08 mm不同直徑、不同表面光潔的細絲材料。選取d 1.75 mm絲材，用OM、SEM和STEM分析材料的組織，用Instron 5500R和彎曲試驗裝置測試細絲的力學(xué)性能。結(jié)果表明：細絲晶粒直徑為1 mm；第一類強化相的平均尺寸為0.5 mm；第二類強化相的平均尺寸小于35 nm；第三類強化相的平均尺寸小于10 nm，且為析出相。擠壓態(tài)細絲的屈服強度、抗拉強度和伸長率分別為237 MPa、297 MPa和12.5%，拉伸模量為115 GPa。經(jīng)過300 ℃保溫10 min空冷熱處理后，材料的屈服強度、抗拉強度和伸長率分別為300 MPa、364 MPa和6%。材料的強度取決于第二和第三類顆粒尺寸與體積分數(shù)，而塑性則取決于第一類強化相的形狀與尺寸。材料的臨界對折壓桿直徑約為5 mm，壓應(yīng)力是細絲彎曲斷裂的控制因素。
關(guān)鍵字: 鎂合金；往復(fù)擠壓；絲材；力學(xué)性能
Mg-Zn-Y-Ce-Zr alloy wires
（1. School of Materials Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, China;
2. School of Economics and Management, Henan Polytechnic University, Jiaozuo 454000, China）
Abstract:The magnesium wires with different diameters from 1.55 mm to 2.08 mm were prepared by reciprocating extrusion and forward extrusion as-cast Mg-6.0%Zn-1.0%Y-0.6%Ce-0.6%Zr. The wires with the diameter of 1.75 mm were analyzed using OM, SEM, STEM, Instron mechanical property equipment and bending tester. The microstructure of the wire consists of fine equiaxed grains with diameter of 1 mm and three different kinds of strengthening particles. The diameter of the first kind particle is 0.5 mm. The diameter of the second kind is less than 35 nm. The diameter of third kind, however, is precipitate forming during hot working. The ultimate tensile strength, tensile strength and elongation of the as-extruded wire are 237 MPa, 297 MPa and 12.5%, respectively. After holding at 300 ℃ for 10 min and then cooling in air, the corresponding yield strength, tensile strength and elongation are 300 MPa, 364 MPa and 6%, respectively. The modulus of elasticity is 115 GPa. The high strength of the wire is determined by the refined grains, the second and third kinds of strengthening particles. However, the elongation is controlled by the first kind strengthening particles. The critical bending diameter controlled by compressive stress is about 5 mm.
Key words: magnesium alloy; reciprocating extrusion; wire; mechanical property
