高抗裂耐磨堆焊焊条的研制

Development of Surfacing Electrode with High Crack and Wear Resistance

为开发高抗裂高耐磨的堆焊焊条,采用H08A焊芯,通过调整药皮中的组分,设计了4种碱性焊条,然后分别在Q235钢基体上进行堆焊,采用光谱仪、硬度计、光学显微镜、扫描电镜和能谱仪等对堆焊层的化学成分、硬度和显微组织进行了分析,并研究了堆焊层的耐磨性和抗裂性。结果表明:优化成分焊条的堆焊层组织为混合型马氏体+少量残余奥氏体+弥散分布的一次NbC-TiC颗粒,低碳马氏体和高碳马氏体数量相当,硬度为58.1 HRC;堆焊层具有高的抗裂性能,连续堆焊不产生宏观裂纹;堆焊层的耐磨性也较好,约为淬火态45钢的1.41倍。

In order to devolop a surfaceing electrode with high crack and wear resistance, four kinds of basic electrode were designed through adjusting chemical composition of coating with H08A core wire which was welded respectively on Q235 steel substrate. The chemical composition, hardness and microstructure of the layer were analyzed by using spectrograph, hardness tester, optical microscopy, SEM and EDAX , and the wear resistance and the crack resistance were investigated. The results show that the microstructure of layer with optimized composition was the mixed martensite and little retained austenite with primary NbC-TiC which was dispersively distributed. The amount of low-carbon and high-carbon martensite was identical, the hardness of deposited metal was 58. 1 HRC. The surfacing metal was crack-free even under the condition of continuous surfacing. The wear resistance was good, which was 1.41 times that of quenched 45 steel.