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影响真空脱气的因素有哪些?

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正确答案:

(1)真空度:真空度是指真空脱气时钢液面上气相分压。由西瓦特定律可知,真空度越高气相分压越低,则脱气效果越好

(2)真空保持时间:真空时间有一个合理控制,根据对钢的要求可以设定不同的真空保持时间,这样的工艺更合理,更有效

(3)吹氩强度:吹氩搅拌影响真空脱气过程,吹氩搅拌强烈会加速钢液流动,使内部钢液上浮不断更新表面脱气过程的钢液,加速脱气过程的进行。通过调节氩气压力,流量控制吹氩搅拌强度;

(4)炉渣状况:炉渣的黏度,渣层的厚度会影响真空条件下脱气处理效果,因此在脱气前要调整好炉渣,使其保持良好的流动性,合理的渣量和炉渣还原性有利脱气

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