The influence of Si additions (0.1, 0.3, 0.6, 1 wt%) on microstructure, hardness and elevated-temperature sliding wear behavior of AX53 magnesium alloy (Mg—5 wt% Al—3wt% Ca) has been investigated by performing a ball-on-disk high-temperature wear test at different temperatures (RT, 100, 150, 200 °C). The results clearly show that without Si addition, the microstructure of the as-cast AX53 alloy consists of dendritic primary α-Mg phase and lamellar eutectic structure consists of layers of α-Mg and (Mg, Al)₂Ca lamellar intermetallic compounds that alternate together. With Si additions, a new intermetallic compound rich in Si can be defined as MgCaSi of a granular, needle and bulky morphologies with different sizes forms within the inter-dendritic regions of α-Mg. Formation of fine granular MgCaSi intermetallic compounds as well-distributed particles is associated with the addition of 0.6 wt% Si. The alloy containing 0.6 wt% Si shows the highest hardness value and the best wear resistance at all temperatures of the wear test. In the Si-containing alloys, weight loss increases with increasing the temperature of wear test compared to the RT wear test regardless of the Si content. However, the Si-containing alloys have lower weight loss than the investigated alloy without Si addition. The wear mechanisms have been also discussed.

通过进行球磨研究了添加Si（0.1、0.3、0.6、1 wt％）对AX53镁合金（Mg-5 wt％Al-3wt％Ca）的组织，硬度和高温滑动磨损行为的影响在不同温度（RT，100、150、200°C）下进行磁盘高温磨损测试。结果清楚地表明，不添加Si，铸态AX53合金的显微组织由树枝状初生α-Mg相组成，层状共晶组织由α-Mg和（Mg，Al）_2层组成Ca层状金属间化合物交替出现。通过添加Si，可以将富含Si的新金属间化合物定义为在α-Mg的树突间区域内具有不同尺寸形式的颗粒状，针状和块状形态的MgCaSi。形成细颗粒状的MgCaSi金属间化合物以及分布均匀的颗粒与添加0.6 wt％的Si有关。含有0.6 wt％Si的合金在磨损测试的所有温度下均显示出最高的硬度值和最佳的耐磨性。与RT磨损试验相比，含Si合金中的重量损失随磨损试验温度的升高而增加，而与Si含量无关。但是，含硅合金的重量损失比没有添加硅的研究合金低。还讨论了磨损机理。