铸型面特性对铸件表面粗糙度的影响

通过对ZL114A熔体在不同特性涂层表面的润湿角和对应铸件表面粗糙度的测量,利用润湿性模型分析了涂层中骨料材料自由能和粒度对铸件表面粗糙度的影响。结果表明,涂层表面材料自由能越低,铝合金熔体在涂层表面上润湿性越差,铸件表面粗糙度(Ra)值越低。铝合金熔体与表面自由能低的滑石粉涂层之间的润湿性随滑石粉粒度的逐渐减小呈先减小后增大的趋势,对应铸件试样表面粗糙度呈先减小后增大趋势。滑石粉粒度为43μm时,涂层和铝合金熔体间润湿角达到155°,铸件表面粗糙度(Ra)值为0.5847μm。

Effects of Casting Mold Interfacial Characteristics on Surface Roughness of Castings

Through measuring the wettability angle of ZL114A melt on different characteristic coating surface and the surfaces roughness of corresponding castings,the effects of free energy and particle size of refractory in coating on surface roughness of the castings were analyzed based on wetting model.The experimental results show that the wettability of the melt on coating surface become worse,and the surface roughness of the castings is decreased with the decrease of surface free energy of coating material.The wettability of aluminum alloy melt on the talcum powder coating surface with low surface energy is firstly decreased and then increased with decreasing in talcum powder particle size,and so do the corresponding surface roughness of casting.With the talcum powder particle size of 43 μm,and the wetting angle between coating and aluminum alloy melt reaching to 155°,the corresponding surface roughness of castings is 0.584 7 μm.