50CrVA弹簧扁钢压标示开裂原因分析  

Analysis of Causes of Cracking at Pressing Label of 50CrVA Spring Flat Steel

作　　者：李祥才[1] 方国璋[1] 张玉森[1] 

机构地区：[1]青岛钢铁控股集团有限责任公司

出　　处：《安徽冶金》2014年第2期31-34,共4页Anhui Metallurgy

摘　　要：对影响50CrVA弹簧扁钢板簧加工时压标示开裂的化学成分、脱碳层深度、夹杂级别、硬度和显微组织原因进行了分析,认为连铸坯连铸过程由于表面增碳使得扁钢近表面局部出现网状碳化物,而网状碳化物由于为硬脆组织,塑性极差,整体承受外力极不均匀,板簧加工时在压标示压力作用下,由于应力集中,在网状碳化物处首先产生微裂纹,随着压力的进一步增强,最终导致扁钢板簧加工压标示开裂。Factors such as chemical composition,decarburization depth,inclusion sizes,hardness and microstructure which may cause the cracking of 50CrVA spring flat steel at pressing label during processing of leaf spring were analyzed.It was found that billet surface carbonization in the process of continuous casting create network carbide at the close surface of 50CrVA flat steel,which has hard and brittle microstructure and the worst plasticity.Under extremely non-uniform external force,microcracking initially forms at network carbide under the effects of the compression force of label pressing due to stress concentration.With increase of the compression force,finally the microcracking develops into cracking at the pressing label of the spring flat steel.

关 键 词：弹簧扁钢 表面增碳 网状碳化物 微裂纹 开裂 

分 类 号：TG142.41[一般工业技术—材料科学与工程]