AE44镁合金油底壳压铸件本体组织与性能分析.pdfVIP

学兔兔 Sep．2010 铸 造 VO1．59 NO．9 FOUNDRY ·895· r～{压铸 1} t， ．． ，．— 一 f AE44镁合金油底壳压铸件本体组织与性能分析 董泰山，龙思远，廖慧敏，刘 勇 (重庆大学材料科学与工程学院，重庆400030) 摘要：通过材料的替代研究，得到了AE44镁合金油底壳压铸件。模拟结果显示该合金的充型能力和凝固顺序等铸造 性能都满足此油底壳的工艺条件。利用OM、SEM、XRD对本体组织和物相分析，结果表明：本体组织主要由Or．一Mg基 体和沿晶界分布的Mg—RE化合物组成，这些化合物主要为AI ，RE 、AI2RE、AI：，2RE 。A1。．RE 和AI RE 稀土相的存 在，对材料性能的提高起到很大的怍用。NA12RE相较粗大，将对性能造成不利影响，应尽量消除。该油底壳本体的室 温屈服强度为140MPa，抗拉强度达到248MPa，明显高于ADC12铝合金材料228MPa的抗拉强度指标，有较好的力学 性能。断口分析表明，该油底壳本体合金的断裂为准解理断裂。 关键词：AE44；油底壳压铸件；本体分析；显微组织；力学性能 中图分类号：TG146．2 文献标识码：A 文章编号：1001—4977(2010)09—0895—04 Structu re and Performance Analysis of Die Casti ng AE44 Magnesium Alloy Oil Pan Body DONG Tai—shan，LONG Si—yuan，LIAO Hui—min，LIU Yong (College of Material Science and Engineering，Chongqing University，Chongqing 400030，China) Abstract：The die cast oiI pan of AE44 magnesium alloy has been developed through the material substitution．The simulation result shows that the casting properties of the alloy，such as filling ability and solidification sequence，can meet the technology requirements of the oil pan．The analysis，by OM，SEM，XRD，of body structure and phase shows that the structure iS mainly composed of o[一Mg matrix and the Mg—RE compounds which were distributed along the grain bounda~．The compounds mainly are AlllRE3，Al2RE，and AI2 12RE088．AI”RE3 and AI2 RE088 phases play a significant role in the ． 12 improvement of the material properties．Al，RE phase should be eliminated due to its coarse size and adverse effect on properties of the alloy．The yield strength of the oil pan iS 1 40 MPa，and the tensile strength iS 248 MPa