Sr变质剂对石膏型精铸ZL114A合金组织与性能的影响

Effects of Sr Modifier on Microstructure and Mechanical Properties of Gypsum Precision Cast ZL114A Alloy

通过ZL114A合金熔体添加和未添加Sr变质剂,研究了熔体处理条件对石膏型精铸热处理试样显微组织及力学性能的影响。结果表明,未变质铸态试样力学性能好于变质试样,而未变质热处理试样力学性能稍差,其主要原因在于Si相热变质不太充分。由于变质试样缩松缺陷很难消除,因此,对于ZL114A合金石膏型复杂薄壁件,采用未变质处理不失为一种选项。

The effects of melt treatment conditions on the mechanical properties and microstructures of plaster casting samples by T5 treatment were studied by adding Sr modifier or not (unmodified and modified) to ZL114A alloy melt. The results show that the mechanical properties of unmodified as-cast specimens were better than those of modified specimens, but the mechanical properties of heat treated unmodified specimens were slightly worse, which was because the thermal modification of Si phase was not enough. It is difficult to eliminate the porosity defect in the modified specimens, thus for gypsum precision casting of complex thin-walled parts of ZL114A alloy, unmodified treatment is an option.