真空压铸技术与应用(Ⅰ)——真空压铸Al-Si-Cu合金固溶处理时Si、Cu分布

Vacuum Die Casting Technology and Application(Ⅰ)——The Change of Si,Cu Distribution in Vacuum HPDC Al-Si-Cu Alloys during Solution Treatment

对真空压铸(50.6kPa真空度)试样进行不同时间的固溶处理,用光学显微镜、扫描电镜、EDS、XRD研究真空压铸Al-Si-Cu合金固溶处理过程中Si、Cu分布的变化。结果表明,试样在500℃固溶处理2h,Si相可以得到较好的尺寸和形态分布,并且表面起泡尺寸小于100μm,相对于普通压铸,真空压铸试样可以得到更加细化的共晶Si粗化;在500℃固溶处理0.5h,Cu部分溶入基体,开始均匀化,共晶Si的粗化、分布不均匀同样会导致Cu元素分布不均匀。

The change of Si, Cu distribution in vacuum HPDC Al-Si-Cu alloys samples（50% vacuum degree） with solution treated at different time was observed and analyzed by optical microscope, SEM, EDS,XRD. Results indicate that Si phase in the vacuum HPDC samples with solution treated 2 h at 500 ℃ has satisfied size and distribution morphology and surface blister is less than 100 μm. The finer eutectic Si particle can be generated in the vacuum HPDC samples compared with common HPDC samples. After solution treated at 500 ℃ for 0.5 h, Cu elements are dissolved into matrix partly to be homogenized, then its distribution is related with Si phase change.