低合金耐磨钢的断裂行为研究  

Study on Fracture Behavior of Low Alloy Wear-resistant Steel

作　　者：赵威威 牛丰勇 左秀荣[1] 吴翔 王中洋[1] ZHAO Weiwei;NIU Fengyong;ZUO Xiurong;WU Xiang;WANG Zhongyang(School of Physics,Zhengzhou University,Zhengzhou 450052,China)

机构地区：[1]郑州大学物理学院,河南郑州450052

出　　处：《热加工工艺》2022年第22期30-34,41,共6页Hot Working Technology

基　　金：河南省科技开放合作项目(182106000016)。

摘　　要：在不同应变速率下进行拉伸试验,对低合金耐磨钢的拉伸性能及断裂行为进行了研究。结果表明,随着应变速率的提高,试验钢的抗拉强度和屈服强度逐渐增加,断后伸长率逐渐下降。采用扫描电镜(SEM)对断口形貌和附近组织及夹杂物进行研究。结果表明,随应变速率的增加,断口平均韧窝尺寸逐渐变大,相同统计平面内解理面面积逐渐变大。断口附近组织存在显微偏析,同一视场出现板条状和粒装两种组织,在裂纹扩展时沿板条组织扩展较平滑,沿碳化物充分析出区域扩展较曲折,在两种组织交界处发生较大的偏转。两种主要的夹杂物被发现,富N的Ti(C,N)夹杂物呈规则多边形,富C的Ti(C,N)呈长条不规则形态,沿轧向分布。两种夹杂物均会导致材料局部弱化,降低材料强度及塑性。The tensile properties and fracture behavior of low alloy wear-resistant steels were studied by tensile experiments at different strain rates. The results show that with the increase of strain rate, the tensile strength and yield strength of the test steel gradually increase, and the elongation decreases gradually. The fracture morphology, microstructure and inclusions near the fracture surface were studied by scanning electron microscopy(SEM). The results show that with the increase of strain rate, the average dimple size of the fracture gradually increases, and the area of the decomposition surface in the same statistical plane gradually increases. In the same field of view, there are two kinds of microstructure, lath and grain,which are smooth along the strip, rough along the full precipitation area of carbide, and larger deflection appears at the junction of the two microstructure. Two major inclusions appear, the N-rich Ti(C, N) inclusions are regular polygonal, and the C-rich Ti(C, N) is in long strip irregular form,which distribute along the rolling direction. Both kinds of inclusions lead to the partial weakening of the material and reduce the strength and plasticity of the material.

关 键 词：低合金耐磨钢 应变速率 韧窝尺寸 TI(C N) 

分 类 号：TG142.72[一般工业技术—材料科学与工程]