金属陶瓷堆焊在中速磨煤机磨碗衬板和磨辊套上的应用

Application of cermet hardfacing on grinding bowl lining plate and grinding roller sleeve in medium speed coal mill

采用明弧自保焊在Q235钢板表面堆焊了金属陶瓷相耐磨层,测定了耐磨层的成分、金相组织、硬度和耐磨性,并和常规焊丝堆焊耐磨层进行了对比。结果表明,金属陶瓷相堆焊耐磨层成分中Cr和C的含量更高,质量分数分别为29.8%和5.8%;堆焊耐磨层中含有强碳化物形成元素,析出的碳化物尺度更加细小;金属陶瓷相呈纤维状分布,垂直于工作面,体积分数高于常规焊丝堆焊耐磨层,达到64.7%;金属陶瓷相堆焊耐磨层的平均硬度为64.7 HRC,高于常规焊丝堆焊耐磨层;金属陶瓷相堆焊耐磨层的耐磨性高于常规焊丝堆焊耐磨层,其磨损失重量仅为常规焊丝堆焊耐磨层的38%。采用金属陶瓷相堆焊耐磨层的磨煤机磨碗衬板及辊套的检修时间可延长1.5~2.0倍。

The surface of Q235 steel plate was overlaid with cermet wear-resistant layer by open arc self-shielded welding.The composition,microstructures,hardness and wear resistance of the hardfaced layer were analyzed,compared with those of the conventional hadfacing wire.The results showed that the contents(mass fraction)of Cr and C of cermet phase in hardfaced layer were higher,which were 29.8%and 5.8%respectively.The cermet hardfaced layer contained strong carbide forming elements,and the precipitated carbides were finer.Cermet phase was distributed in fiber shape,perpendicular to the working surface.Volume fraction of the cermet phase was 64.7%,higher than that of conventional hardfacing wire.The average hardness of cermet hardfaced layer was 64.7 HRC,higher than that of conventional hardfacing wire.Wear resistance of cermet phase hardfaced layer was higher than that of conventional hardfacing wire,and its wear loss was only 38%of that of conventional hardfacing wire.Maintenance cycle of grinding bowl liner and roller sleeve of coal mill with cermet phase hardfaced wear-resistant layer could be prolonged by 1.5~2.0 times,and remarkable economic benefits were obtained.