In order to explain the morphology and structure of coating precursor shell on the surface of aluminum silicon alloy, the Al-12 wt%Si powders were treated in two kinds of water vapor generation autoclaves, and the water vapor parameters were numerically simulated. The morphology of reactant products was observed by scanning electronic microscopy and analyzed combined with numerical simulation results. The results show the water vapor, liquid water and air co-exist with different distributions. Under the same temperature and pressure, the higher amount of water vapor leads to the formation of stable flake-like boehmite, while the lower amount of water vapor slows down the reaction rate of Al-Si with water, and stable bayerite with prism-like are formed on the surface of Al-Si particles. Different shapes of bayerite, boehmite and pseudo-boehmite are formed on the Al-Si particle surface because of no-uniform distribution of water vapor. This study provides suggestions on selecting the proper establishment and the water vapor parameters for getting the ideal morphology of reactants on the surface of aluminum alloy particles.

为了解释铝硅合金表面涂层前驱体壳的形貌和结构，将Al-12 wt%Si粉末在两种水蒸气发生釜中进行处理，并对水蒸气参数进行数值模拟。通过扫描电镜观察反应产物的形貌，并结合数值模拟结果进行分析。结果表明，水蒸气、液态水和空气以不同的分布共存。在相同的温度和压力下，较高的水蒸气量会导致形成稳定的片状勃姆石，而较低的水蒸气量会减慢 Al-Si 与水的反应速度，而稳定的三羟铝石则具有棱柱状形成在铝硅颗粒表面。不同形状的三羟铝石，由于水蒸气分布不均匀，在铝硅颗粒表面形成了勃姆石和假勃姆石。本研究为选择合适的装置和水蒸气参数提供了建议，以获得铝合金颗粒表面反应物的理想形态。