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用熔模铸造工艺和溶胶－凝胶方法在壳型内表面制备成分９８．５６％ ＳｉＯ２－１．４４％ Ｂ２Ｏ３（ｍｏｌ％）玻璃涂层，ＸＲＤ分析结果表明，该涂层经过（１１７３±５） Ｋ保温３０ｍｉｎ后，再经过（１７７３±５） Ｋ保温６０ｍｉｎ处理无析晶。过冷Ｃｕ_５０Ｎｉ_５０合金熔体在该涂层壳型中遗传的最大过冷度为２３６Ｋ。金相和ＥＤＳ分析表明，凝固组织可以通过两个临界过冷度分为三类：△Ｔ＜７１Ｋ，凝固组织由普通技晶渐变为第一类粒状晶；７１Ｋ＜△Ｔ＜１９２Ｋ为深过冷技晶；△Ｔ＞１９２Ｋ时为通过再结晶后形成的第二类粒状晶。利用ＢＣＴ模型计算结果可以很好地解释三类凝固组织。
The glass coating with composition of 98.56% SiO2-1.44% B2O3 (mol%) was prepared on the inner surface of the shell by means of investment casting and sol-gel method. The XRD results showed that the coating passed through (1173 ± 5 ) K incubated for 30min, and then after (1773 ± 5) K incubated for 60min without precipitation. The maximum undercooling degree inherited by the overcooled Cu_50Ni_50 alloy melt in the coated shell is 236K. Metallographic and EDS analyzes show that the solidified microstructure can be divided into three types by two critical degrees of undercooling: △ T <71K, the solidified structure gradually changes from common crystal to first type of granular crystal; 71K <△ T <192K is deeper than Cold crystal; △ T> 192K when the recrystallization formed by the second type of granular crystal. Using BCT model to calculate the results can well explain three types of solidified tissue.