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利用溶胶－凝胶方法，在铸型内表面玻璃涂层上制备 ＳｉＯ２晶态和非晶态薄膜涂层，将深过冷 的Ｃｕ７０Ｎｉ３０。合金熔体浇入两种涂层铸型中．分别获得９０Ｋ和１９８Ｋ的过冷度．提出了用重合密度和重 合原子中心偏离度分析涂层结构对合金熔体形核惰性影响的模型．用ＢＣＴ模型分析过冷熔体凝固过程中 枝晶生长与过冷度的关系，结果表明， ８０Ｋ为临界过冷度，△Ｔ＜８０Ｋ时，枝晶生长受成分过冷控制； △Ｔ＞８０Ｋ时，受热过冷控制．在深过冷范围内．凝固组织为细密挺直枝晶．
The sol-gel method was used to prepare SiO2 crystalline and amorphous thin film coatings on the inner surface glass coating of the molds, and the supercooled Cu70Ni30 was prepared. The alloy melt is poured into two coating molds. Obtained 90K and 198K of subcooling. A model was proposed to analyze the inertness of the coating structure to the nucleation of the alloy melt by the coincidence density and the center deviation of the coincident atoms. BCT model was used to analyze the relationship between dendrite growth and undercooling in the process of subcooled melt solidification. The results show that the dendrite growth is controlled by the undercooled condition when △ T <80K at 80K; △ T> 80K When heated undercooling control. Deep in the cold range. Solidified tissue is fine and straight dendrite.