10CrNiCu钢冷弯裂纹分析  

Study on cold-bend cracks of 10CrNiCu steel

作　　者：陈庆丰[1] 严翔[1] 刘武群[1] 罗国华[1] 张光新[2] 

机构地区：[1]武汉钢铁(集团)公司研究院,湖北武汉430080 [2]武汉钢铁(集团)公司轧板厂,湖北武汉430083

出　　处：《钢铁研究》2007年第4期20-22,共3页Research on Iron and Steel

摘　　要：10 CrNiCu钢冷弯裂纹有两种:一种宽长,另一种细小。宽长裂纹试样浅表层处出现粗晶区,粗晶内部为长条状或多边形状结构,长板条最长可达50μm。粗晶区硬度比钢板内部细晶区的硬度低42HV0.1,浅表层与内部组织、性能的差异导致钢板弯曲时开裂。粗晶区原奥氏体晶界上出现了断续呈链状分布的铁素体组织,说明钢板回火时表面温度超高,导致浅表层组织相变,析出铁素体。细小裂纹是由钢板表面残留氧化铁皮引起的。Two types of cold-bend cracks were observed in 10CrNiCu steel. One type showed the large size morphology, the other showed fine size. Around large size cracks, coarse grains were observed near the sample surface. Strip or polygonal microstructure was found in coarse grains and the longest lath was up to 50 m. The hardness on coarse grain zones was 42 HV0.1 lower than that on fine grain zones within steel. The difference of microstructure and properties between the coarse grains region and fine grain size region is the main factor which causes the steel plate impair when being bent. Chain shape ferrites were observed on austenite grain boundary in coarse grain zones and the distribution of ferrites was discontinuous. This phenomenon implies that the temperature on the plate surface is so high that the phase transformation occurs near the surface region. During the cooling process, the ferrites precipitate around grain boundaries. The fine size crack is caused by residual scale on steel plate surface.

关 键 词：冷弯裂纹 晶粒粗大 回火温度 氧化铁皮 

分 类 号：TG146.91[一般工业技术—材料科学与工程]