轧制加工低合金板钢表面边部裂纹机制研究

Study of Rolled Plate Surface Edge Crack on Microalloy Steel

通过"模铸+初轧"工艺轧制低合金钢锭时,钢板易在表面距边部100 mm左右易出现直线型裂纹,裂纹或深或浅,有规律,导致报废量大大增加,影响了正常生产。该类缺陷曾被认为是轧制缺陷,从宏观形貌及微观组织等多方面研究缺陷形成机制,判定源于钢锭表面内在和外在微裂纹缺陷,初轧轧制时轧件在受到拉应力最大的地方产生开裂,从而为产品质量改进提供了理论依据,通过采取有效的技术措施,大大减少了该类缺陷发生的几率。

Linearity crack sometimes appears on microalloy steel plate surface about 100mm from edge in ＂ingot casting ＋ bloom rolling＂,which is regularly deep or shallow,and conduces so much waste product that affects normal production.Based on macro-scopical shape and micro-structure research,these faults were thought of coming from steel ingot surface microcrack rather than rolling default.Microalloy steel plate will craze at the most pull-stress position,which provides theoretical foundation for product quality improvement.These faults have greatly reduced after adopting effective technique measures.