喷射成形60Si-40Al合金热压缩与热挤压工艺研究.pdfVIP

学兔兔 第 19卷第5期 粉 末 冶 金 工 业 Vo1．19 No．5 2009年lO月 POWDER METALLURGY INDUSTRY 0Ct．2009 喷射成形60Si一40A1合金热压缩与热挤压工艺研究 王进学，刘允中，王 洁，肖文华 (华南理工大学机械与汽车工程学院，广州 51O640) 摘 要：热挤压是提高喷射成形60Si一40Al合金锭坯致密度和性能的加工工艺之一。为了全 面了解热挤压过程对该材料变形的影响，先采用等温热压缩实验获取该材料的高温塑性变形 特征；而后采用数值模拟与工艺试验相结合的方式对热挤压过程进行研究，数值模拟结果和实 验结果吻合较好。研究结果表明：变形过程中喷射成形60Si-40A1合金流变应力受变形温度 和应变速率的影响尤为明显，流变应力随变形温度升高而降低，随应变速率提高而增大；对于 热挤压加工而言，该材料最佳工艺参数为：挤压温度45O～520℃，挤压比25～3O。 关键词：喷射成形；60Si一40Al舍金；热压缩；热挤压；数值模拟 中图分类号：TF124．36 文献标识码：A 文章编号：1006—6543(2009)05—0024—06 RESEARCH 0N ISOTHERMAL C0MPRESSION AND HOT EXTRUSION TECHNOLOGY SPRAY FORMED 60Si一40Al ALLOY Wang Jin-xue Liu Yun-zhong Wang Jie Xiao Wen-hua (1．School of MechanicalAutomative Engineering，South China University of Technology，Guangzhou China) Abstract：Hot extrusion process is one of the effective approaches to increase density and im— prove performance for spray—formed 60Si一40A1 alloy．Inorder to obtain the plastic deformation features of the alloy，isothermal compression tests were performed on Gleeble一1500 ma— chine．The hot extrusion process of spray—formed 60Si一40A1 alloy，then，was studied by nu— merical simulation and experiment and simulation results agreed well with experimental ones．The results show that the flow stress strongly depends OH the deformation tempera— tures and strain rate，the flow stress increases with strain rate and decreases with the increase of deformation temperature．The obtained optimal processing parameters of extr