摘要
采用金相显微镜、扫描电镜分析了镀锌钢板180°冷弯时出现开裂的原因。发现裂纹附近的显微组织除发生轻微变形外,未见明显夹杂物和组织偏析;开裂属于韧性断裂,断裂方式与受力方向相同;开裂处有大量硅酸盐、硫化物和结晶器保护渣的复合夹杂物。认为镀锌钢板中大量的硫化物和硅酸盐夹杂物是造成钢板冷弯开裂的主要原因,对炼钢工序提出了相应的改进措施,实施后,未出现过180°冷弯开裂现象。
The reason for the 180°cold bending cracking of galvanized steel sheet is analyzed with metallographic microscope and SEM. It is found that in the micro structure around the cracks there is no obvious inclusion and structure segregation besides light deformation; the cracks belong to ductile fracture, fracture way is same with the direction of force; there is at cracks a large amount of complex inclusion of silicate, sulfide and mold casting powder. It is considered that a large amount of sulfide and silicate inclusion in galvanized steel sheet is the main reason for cold bending cracking, some relative improving measures for steel making procedure proposed. After those measures carried out the defect is not brought about again.
出处
《河北冶金》
2015年第5期22-25,59,共5页
Hebei Metallurgy
关键词
镀锌钢板
冷弯
开裂
组织
夹杂物
galvanized steel sheet
cold bending
cracking
structure
inclusion
