Monel K-500 合金电渣重熔锭内裂纹分析及改进措施

Crack analysis and improvement measures of Monel K-500 alloy electroslag remelting ingot

本文针对Monel K-500合金电渣锭应力开裂问题,通过金相分析、直读光谱和电子探针等手段,判断电渣锭内部缺陷为热裂纹。利用热力学计算和高温共聚焦凝固过程表征等方法分析Monel K-500凝固行为,确定较高的Si含量是造成电渣锭热裂纹主要原因。通过工业试验发现,将Si含量由0.4%降至0.1%以下,可有效降低合金凝固区间,改善凝固组织,从而消除电渣锭内裂纹形成倾向。

In this paper,the internal cracks of Monel K-500 electroslag ingots were studied,and the internal defects of electroslag ingots were determined as thermal cracks by means of metallographic analysis,direct reading spectroscopy and electron probes.Thermoel calculation and high temperature confocal analysis were used to analyze Monel.K-500 solidification behavior,determining the higher Si content is the main cause of thermal cracking of electroslag ingots.Industrial tests have shown that reducing the Si content of the original alloy to less than 0.1%can effectively reduce the solidification interval of the alloy and improve the solidification structure,thereby eliminating cracks in the electroslag ingot.