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研究了等温处理工艺和压射速度对触变压铸Al-30Si合金(加入1%的磷盐变质处理)组织和力学性能的影响。结果表明,触变压铸组织和常规铸锭组织相比,初生Si的形貌更加圆整,针状的共晶Si消失,而α-Al的的枝晶被打碎,以弥散的颗粒状分布;在固相率较高时,部分α-Al未熔化,以固相保留下来,形态为球状或近球状。常温下的抗拉强度在620℃保温100min和120min时,都随压射速度的增加呈现出先增大后减小的趋势,前者的最大值出现在6m/s,为226MPa;而后者的最大值出现在4m/s,为230MPa。在630℃保温120min时,抗拉强度随压射速度的增加而逐渐减小。
The effects of isothermal treatment process and injection speed on the microstructure and mechanical properties of thixotrope-cast Al-30Si alloy (adding 1% phosphorus salt) were studied. The results show that, compared with the conventional ingot, the thixotrope structure is more rounded and the needle-shaped eutectic Si disappears, while the dendrites of α-Al are disintegrated to disperse the granular distribution When the solid fraction is high, part of α-Al is not melted and remains in the solid phase. The morphology is spherical or nearly spherical. Tensile strength at room temperature at 620 ℃ for 100min and 120min both showed a trend of first increasing and then decreasing with the increase of the injection velocity. The maximum of the former appeared at 6m / s, which was 226MPa. The latter’s maximum Appear in 4m / s, is 230MPa. At 630 ℃ for 120min, the tensile strength decreases with the increase of the shot velocity.