【摘要】 为了抑制高硼铁基耐磨堆焊合金硬质相Fe₂B内部的显微裂纹，改善堆焊合金层的耐磨性能，向Fe-B-C系耐磨堆焊合金中添加不同含量的Cr，研究Cr含量对堆焊层组织形貌、物相组成及硬度的影响。试验采用添加不同含量微碳铬铁粉的方式，利用等离子粉末堆焊的工艺，在Q235钢板上制备具有不同Cr含量的高硼铁基堆焊合金，通过光学显微镜、XRD,SEM,EDS及洛氏硬度等方法对耐磨堆焊层的组织形貌、物相组成及硬度进行了分析。研究结果表明，未添加微碳铬铁粉时，堆焊合金层由初晶Fe2B相和共晶组织α-Fe+Fe₃（C,B）组成;当微碳铬铁粉的添加量为30%时，出现新的初晶相Fe_1.1Cr_0.9B_0.9; Cr元素具有促使堆焊层组织硬质相Fe2B析出的作用，并且能有效抑制初晶Fe₂B相显微裂纹的产生;堆焊层的硬度随Cr含量的增加而增加，当微碳铬铁粉添加含量为55%时，硬度高达到65.5 HRC。更多还原

【Abstract】 In order to inhibit the microcracks in the hard phase Fe₂B of the high B Fe-based wear-resistant surfacing alloy and improve the wear resistance of the surfacing alloy layer,different content of Cr was added to the Fe-B-C based wear-resistant surfacing alloy to study influence of Cr content on morphology,phase composition and hardness of the surfacing layer. Method of adding different content of micro-carbon ferrochromium powder was adopted in the experiment,plasma powder surfacing process was used to prepare high-B Fe-based surfacing alloys with different Cr contents on the Q235 steel plate,and morphology,phase composition and hardness of the surfacing layer were analyzed through methods of optical microscope,XRD,SEM,EDS and Rockwell hardness. The results showed that the surfacing alloy layer was composed of primary Fe₂B phase and eutectic structure α-Fe + Fe₃（ C,B） with no addition of micro-carbon ferrochrome powder,and new primary crystal phase Fe_{1. 1}Cr_{0. 9}B_{0. 9}with 30% addition amount of micro-carbon ferrochromium powder. Cr element had effect of promoting precipitation of the hard phase Fe₂B in the surfacing layer,and could effectively inhibit generation of microcracks in the primary Fe₂B phase. Hardness of the surfacing layer increased with the increase of Cr content,which was as high as 65. 5 HRC with 55% addition amount of microcarbon ferrochromium powder.更多还原