压射速度对压铸Al-20%Si合金组织与性能的影响  

Influence of Injection Speed on Microstructure and Mechanical Property of Die Casting Al-20% Si Alloy

作　　者：孙俊[1] 李京[1] 李宝礼[1] 田载友 

机构地区：[1]海军驻兴平地区军事代表室,陕西兴平713105 [2]中船重工集团第十二研究所,陕西兴平713102

出　　处：《热加工工艺》2010年第15期38-40,43,共4页Hot Working Technology

基　　金：甘肃省自然科学基金资助项目(3ZS062-B25-026);兰州理工大学博士基金资助项目(SB01200406)

摘　　要：基于液态压铸技术,研究了压射速度对Al-20%Si合金显微组织与性能的影响,同时利用扫描电子显微镜(SEM)对其拉伸断口形貌进行分析。结果表明:随着压射速度的增大,试样的抗拉强度、伸长率和冲击韧度先增大而后减小,硬度总的趋势是降低的,但硬度值变化不大。合金的断裂方式为解理断裂。在实验条件下,增压压力16MPa、模具温度150℃、浇注温度720℃、压射速度2.5m/s时,压铸Al-20%Si合金的力学性能较优,其力学性能可以达到:σb=280MPa、δ5=4.83%、Ak=25.56 J/cm2、硬度=80.6HBS。The influence of injection speed on the microstructure and mechanical properties of die casting Al-20%Si aluminum alloy was investigated by liquid die casting technology,and the fracture surface was analyzed by scanning electron microscopy.The results indicate that with the increase of the injection speed,the tensile strength,percentage elongation and impact toughness firstly increases and then decreases,while the hardness decreases;the fracture mode of the material is cleavage fracture.Under the experiment conditions,at the injection pressure of 16 MPa,die temperature of 150 ℃,pouring temperature of 720 ℃ and injection speed of 2.5 m/s,the mechanical properties of Al-20%Si alloy is better,σb=280 MPa,δ5=4.83%,Ak=25.56 J/cm2 and H=80.6 HBS.

关 键 词：AL-SI合金 压射速度 组织 力学性能 

分 类 号：TG249.2[金属学及工艺—铸造]