挤压工艺参数对喷射沉积AlFe VSi合金棒材组织性能的影响  

Effect of processing parameters on microstructurea and mechanical properties of hot-extruded bar of spray deposited AlFeVSi aluminum alloy

作　　者：肖于德[1] 黎文献[1] 谭敦强[1] 马正青[1] 王日初[1] 

机构地区：[1]中南大学材料科学与工程学院,长沙410083

出　　处：《粉末冶金技术》2004年第5期270-274,共5页Powder Metallurgy Technology

基　　金：国家重点基础研究发展规划资助项目 (G19990 6 4 90 0 );国家"九五"攻关项目 (95 -YS - 0 10 )

摘　　要：采用雾化粉末 -冷等静压工艺和喷射沉积工艺制备快凝AlFeVSi合金坯料 ,通过透射电镜、扫描电镜、拉伸力学性能测试等手段研究挤压温度、挤压变形系数以及加热时间等工艺参数对喷射沉积AlFeVSi合金组织性能的影响。选择合适的工艺参数 ,挤压制备了喷射沉积AlFeVSi合金棒材 ,并以快凝雾化粉末AlFe VSi合金挤压棒材为参考对象 ,对比分析了喷射沉积AlFeVSi合金棒材室温、高温拉伸力学性能。结果表明 ,挤压温度不宜高于 5 0 0℃ ,否则棒材强度和塑性则会因有粗大块状θ Al1 3Fe4 相出现而急剧下降。喷射沉积AlFeVSi合金挤压棒材的抗拉强度和伸长率均随挤压变形系数增大而单调提高 ,当挤压比λ大于 16后 ,抗拉强度和伸长率趋于稳定。选择合适的工艺参数 (挤压温度 4 80℃ ,加热时间 3h ,挤压比 2 5 ) ,可以制备室温、高温力学性能良好的喷射沉积AlFeVSi合金挤压棒材。Rapidly solidified blanks of AlFeVSi heat-resistant aluminum alloy were prepared by cold-isostatic pressing of atomized powder and spray deposition of melted metal. Influence of processing parameters, such as extrusion temperature, pre-heating time and extrusion ratio, on microstructures and mechanical properties of spray deposited AlFeVSi aluminum alloys was studied by means of transmission electron microscopy, scanning electron microscopy and measurement of tensile properties. Suitable processing parameters were selected to extrude spray deposited blanks into bars, and tensile properties of the extruded bars were examined at room temperature and high temperature of 350℃ and compared with those of rapidly solidified AlFeVSi alloy produced by atomized powder. The results show that the extrusion temperature ought not to be higher than 500℃, or tensile strength and plasticity of the extruded bars will decrease dramatically owing to coarse lumpish θ-Al 13Fe 4 phase appearing. Both of tensile strength and elongation of spray deposited AlFeVSi extruded bars increase monotonously with extrusion ratio increasing, and when extrusion ratio is larger than 16, it has a gradually weakening effect on tensile strength and elongation of the extruded bars. The extruded bars of spray deposited AlFeVSi aluminum alloy with excellent tensile strength and plasticity at room and high temperature can be prepared in suitable conditions with extrusion temperature being 480℃, pre-heating time being 3h and extrusion ratio being 25.

关 键 词：棒材 喷射沉积 合金 挤压工艺 组织性能 挤压比 快凝 VS 影响 对比分析 

分 类 号：TF124[冶金工程—粉末冶金] TG146[冶金工程—冶金物理化学]