摘要
研究350℃热暴露200 h对金属型铸造与高压铸造Al-Si-Cu-Ni-Mg合金组织和力学性能的影响。用扫描电镜和图片分析软件IPP表征合金中硅相的形貌。研究结果表明,高温热暴露促进共晶硅的球化和粗化。热暴露后,高压铸造合金的室温抗拉强度高于金属型铸造的,但350℃时两种合金的高温抗拉强度均为67 MPa左右。由于共晶硅的粗化,热暴露后金属型铸造合金的抗蠕变性能均优于高压铸造合金。因此,拥有细小尺寸共晶硅的合金不适于在350℃的条件下应用。
The effect of thermal exposure at 350 ℃ for 200 h on microstructure and mechanical properties was investigated for Al-Si-Cu-Ni-Mg alloy, which was produced by permanent mold casting(PMC) and high pressure die casting(HPDC). The SEM and IPP software were used to characterize the morphology of Si phase in the studied alloys. The results show that the thermal exposure provokes spheroidization and coarsening of eutectic Si particles. The ultimate tensile strength of the HPDC alloy after thermal exposure is higher than that of the PMC alloy at room temperature. However, the TEPMC and TEHPDC alloys have similar tensile strength around 67 MPa at 350 ℃. Due to the coarsening of eutectic Si, the TEPMC alloy exhibits better creep resistance than the TEHPDC alloy under studied creep conditions. Therefore, the alloys with small size of eutectic Si are not suitably used at 350 ℃.
作者
张嘉盈
左立杰
冯剑
叶兵
孔向阳
蒋海燕
丁文江
Jia-ying ZHANG;Li-jie ZUO;Jian FENG;Bing YE;Xiang-yang KONG;Hai-yan JIANG;Wen-jiang DING(National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composites,Shanghai Jiao Tong University,Shanghai 200240,China;School of Mechanical and Ocean Engineering,Jiangsu Ocean University,Lianyungang 222005,China;GRIMAT Engineering Institute Co.,Ltd.,Beijing 101407,China;Institute of Materials for Mobile Energy,School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)
基金
Projects(2016YFB0700502,2016YFB0301001)supported by the National Key Research and Development Program of China。
