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采用重力铸造和离心铸造方法分别制备了Al-9Ni-19Si复合材料铸件。观察了两种铸造工艺成形铸件的微观组织特征,测试了铸件的硬度及耐磨性能。结果表明:重力铸造Al-9Ni-19Si铸件中,初生Al3Ni/Si颗粒在整体上呈现随机分布的状态;而离心铸造Al-9Ni-19Si铸件形成了3层组织,即聚集有大量初生Al3Ni/Si颗粒的外层,含有较多的初生Si/Al3Ni颗粒的内层以及不含颗粒的中间层。重力铸造铸件的初生Al3Ni/Si颗粒体积分数为19.8%~32.0%,硬度值为44~51HRB,其耐磨体积损失量为19.78 mm3;而离心铸造筒状零件外层的初生Al3Ni/Si颗粒体积分数最高可达41%,硬度值为52.5~72.0 HRB,外层的耐磨体积量为11.96 mm3。离心铸造Al-9Ni-19Si铸件获得了具有高颗粒体积分数的初生Al3Ni/Si,增强了复合材料,其硬度及耐磨性能优于重力铸造铸件。
Al-9Ni-19Si composite castings were prepared by gravity casting and centrifugal casting respectively. The microstructural features of the two casting processes were observed and the hardness and wear resistance of the castings were tested. The results show that the Al3Ni / Si primary particles are randomly distributed in Al-9Ni-19Si castings. Three layers of Al-9Ni-19Si castings are formed by centrifugal casting, that is, a large amount of primary Al3Ni / The outer layer of particles, the inner layer containing more primary Si / Al3Ni particles and the intermediate layer without particles. The volume fraction of primary Al3Ni / Si particles in gravity casting castings is 19.8% ~ 32.0%, hardness is 44 ~ 51HRB, and wear resistance volume loss is 19.78 mm3. However, the volume fraction of primary Al3Ni / Si particles in the outer layer of centrifugal casting is The scores are up to 41%, the hardness values are 52.5 to 72.0 HRB, and the outer wear volume is 11.96 mm3. Centrifugal casting of Al-9Ni-19Si castings obtained with a high volume fraction of primary Al3Ni / Si, enhanced composite materials, its hardness and wear resistance is superior to gravity casting castings.