摘要
探讨同炉同批同工艺的SWRH82B盘条拉拔脆断产生原因。对试样进行力学性能检验,有2根试样断面收缩率不合格,其中1#试样为11.00%,2#试样为25.94%。采用扫描电镜观察脆性断口形貌,并对金相组织分析后得出结果:(1)1#试样脆断主要原因是钢中存在大型铝酸盐夹杂物和网状渗碳体组织,使得盘条的强度和塑性均显著下降;(2)2#试样网状渗碳体很少、很薄,而且索氏体率很高,断面收缩率稍低的主要原因是在塑性变形时产生的位错堆积引起应力集中,表现为纤维区大、剪切唇厚和螺旋台阶。采用线弹性断裂力学理论证明结果与两试样断裂试验结果相符。
To discuss the reason of same furnace, batch and process SWRH82B wire rod drawing fracture. The sample was mechanical properties tested. The reduction of area of two samples is below standard. The first sample is 11.00%, second is 25.94%. Brittle fracture pattern was examined by SEM and mierostructure was analyzed. The conclusion that large aluminate inclusions and network cementite structure is main reason of the first sample brittle fracture, which decreased wire rod strength and plasticity obviously, the second sample network cementite is small and thin and percentage of sorbite is high, the main reason caused area reduction low is dislocation accumulation inducing stress concentration produced in plastic deformation, which displayed fiber region big, shear lips thick and spiral step. The proved result of adopting linear elasticity fracture mechanics is corresponded with two samples fracture test result.
出处
《金属制品》
2010年第3期44-47,共4页
Metal Products
基金
贵州省科学技术基金:黔科合J字[2007]2187号
关键词
SWRH82B盘条
脆断
脆性夹杂物
网状渗碳体
位错堆积
SWRH82B wire rod
brittle fracture
brittle inclusion
network cementite
dislocation accumulation
