铆螺钢镦裂原因分析

Analyses of Cracking of Cold Forging Steel

通过理化检测,对铆螺钢在冷镦时出现开裂的原因进行了分析。结果表明：铆螺钢冷镦中出现的开裂为塑性开裂；原料在冶炼过程中,中间包内衬出现塌落,使钢中存在较多含有氧、锰、铁、镁、铝、硫和钙等元素的层皮状夹杂物,它不同于钢中的正常夹杂物,是造成铆螺钢镦裂的根本原因。

The reason of cracking for the cold forging steel was analyzed by physical and chemical tests. The fracture morphology of the cold forging steel was plastic fracture. The falling down of the liner in the tundish during smelting of the bar resulted in the presence of larger amount of complex inclusions containing dements of O, Mn, Fe, Mg, Al, S and Ca. These inclusions resulted in cracking of the cold forging steel during the cold heading process.