铌和氧化铈对堆焊金属耐磨性及冲击韧性影响

在自保护药芯焊丝中添加不同量的Nb和氧化铈，分析Nb和氧化铈对堆焊层组织和性能的影响．测试了堆焊层的硬度和冲击韧性，使用自制干砂一橡胶轮装置进行堆焊层试样的磨粒磨损测试．使用光学显微镜、扫描电镜和x射线衍射分析堆焊层的组织，并使用扫描电镜分析了堆焊层磨损后的表面形貌．结果表明：Nb和稀土氧化铈都可以细化堆焊金属，从而使得堆焊金属的硬度提高；Nb的添加对提高堆焊金属的冲击韧性有一定的影响，但是效果不如稀土氧化铈明显；堆焊层的磨损形式主要为显微切削和“犁”作用2种形式，添加Nb和稀土氧化铈后，堆焊层的耐磨性有明显提高．

Effect of Nb and ceria on wear resistance and impact toughness of hardfacing metals

Different amounts of Nb and ceria were added into self-shielded flux cored wires to analyze the effects of Nb and ceria on the microstructure and properties of hardfacing metals.The hardness and impact toughness tests of hardfacing deposits were applied.The abrasion tests were carried out using dry sand-rubber wheel machine.Optical scanning,electron microscopy and XRD were used for the microstructure of deposits,and the worn surface of deposits was analyzed by electron microscopy.The results show that both Nb and ceria can refine the microstructure of deposit,so that the hardness value of deposits is increased.The addition of Nb can improve the impact toughness of deposit to some extent,but not better than addition of ceria.Micro-cutting and micro-ploughing are the main abrasive micro-mechanisms,and the wear resistance of deposits is improved with the addition of Nb and RE oxides.