喷射沉积硅铝合金组织结构与性能的分析

用自行研制的喷射装置制备硅铝合金坯体 ,分析喷射沉积坯体的组织结构及固溶处理后的组织变化 ,测试对热挤压后坯件拉伸、表面硬度、耐磨等性能。在较高过冷度下 ,熔体形核率增加、沉积时液滴的冲击使初生硅破碎 ,细化了硅铝合金组织。固熔处理温度、保温时间对硅铝合金组织影响较大。喷射沉积挤压硅铝合金力学性能与铸造组织相比 ,抗冲击性能大幅提高 ,硬度提高 3 0 % ,耐磨性提高 2 5 %。

Texture and Property of Spraying Deposition Si-Al Alloy

The rough blank of Si-Al alloy is prepared by self-made spraying deposition apparatus, the texture of rough blank and the structure evolution after solid solution treatment are analyzed, and the properties for stretching, abrasion and surface-hardness are determined. Under the deep over-cooled condition, the primary silicon is broken and the grain size of the rough blank texture is fined by the effects of the increase of nucleus formation rate and the alloy drops impact while depositing. There are obvious effects of temperature and retention time for solid solution treatment on the rough blank texture. Compared to the casting texture in mechanical properties, the shock resistance of the rough blank texture is greatly increased, the hardness is increased by 30%, and the abradability by 25%.