电渣重熔高温合金渣系对冶金质量的影响

Influences of slag system on metallurgical quality for high temperature alloy by electroslag remelting

电渣重熔渣系的组成直接关系到高温合金的冶炼质量和表面质量。分析了高温合金电渣重熔渣系选择的基本要求和组成特点,确定了高温合金电渣重熔常用渣系的基本类型。通过研究高温合金电渣重熔渣系对冶金质量的影响可知：高碱度渣系具有较好的脱硫效果;为了降低渣料中的不稳定氧化物,应在使用前对萤石进行提纯;可以采用改变渣系组元和加入铝粉的方法,从而减少铝、钛等易氧化元素的烧损;选择低熔点渣系,可有效减少和避免含钛高温合金在电渣重熔过程中易出现的锭身表面渣沟、腰带缺陷、锭身分流眼等表面缺陷。提出的高钛低铝型高温合金电渣重熔渣系配比（质量分数）为：Ca F265%~70%、Al2O312%~15%、Ca O 12%~15%、Mg O 3%~8%、Ti O22%~5%。高铝低钛型高温合金电渣重熔渣系配比（质量分数）为：Ca F260%~65%、A12O315%~20%、Ca O 15%~20%、Mg O 0~5%、Ti O20%~2%。

The composition of electroslag remelting（ESR）slag system is directly related to smelting quality and surface quality of high temperature alloy. This study analyzed basic requirements and composition characteristics of ESR slag system for high temperature alloy. Basic types of ESR slag system for high temperature alloy were determined. Through the research on the influences of ESR slag system for high temperature alloy on metallurgical quality,it can be known that slag system with high alkalinity is beneficial to desulfurization. In order to reduce unstable oxide,fluorite should be purified before using. Changing slag system composition and adding aluminum powder can reduce the burning of Al,Ti and other active elements. The application of slag system with low melting point can reduce or avoid surface slag runners,waist defects and shunt holes in the ESR process for high temperature alloy with Ti. The slag system composition proposed in this article for high temperature alloy with high Ti content and low Al content is that Ca F265% ~70%、A12O312%-15%、Ca O 12%-15%、Mg O 3%-8%、Ti O22%-5%. The slag system composition proposed in this article for high temperature alloy with low Ti content and high Al content is that Ca F260%-65%、A12O315%-20%、Ca O 15%-20%、Mg O 0%-5%、Ti O20%-2%.