添加钨铁粉对WC/钢基表面复合材料界面及硬度的影响

Influence of addition of tungsten-iron powder on interface and hardness of WC/steel composite coatings

采用真空铸渗工艺制备了WC/Cr15钢基表面复合材料,研究了在预置层中添加16.7 vol%钨铁粉对复合层的界面组织和基体硬度的影响。运用OM、SEM、XRD和显微硬度计对复合层的界面组织和基体硬度进行了分析。结果表明,添加16.7vol%钨铁粉改善了复合层的界面组织及力学性能的连续性,有利于降低应力集中,改善应力分布状态;反应层中形成过渡均匀分布的Fe3W3C相,使WC颗粒与基体之间形成组织过渡;复合层基体中形成弥散分布的Fe3W3C相,提高了复合层的基体硬度,增强了复合层基体的耐磨性及其对WC颗粒的支撑与固定作用。

WC particles reinforced steel matrix composite coatings on Cr15 steel substrate was fabricated using vacuum infiltration-casting technique.Microstructure and hardness of the composite coatings by adding 16.7 vol% tungsten-iron powder into the preform layer were studied by means of optical microscopy,scanning electron microscopy with energy spectrometer,X-ray diffraction and micro-hardness test.The results show that the microstructure and mechanical properties of the interface of the coatings prepared with the preform layer added 16.7 vol% tungsten-iron powder are improved.Fe3W3C phase is observed in the coatings,which becomes the transition microstructure between the WC particle and the matrix.Uniformly distributed Fe3W3C phase in the matrix increases hardness and wear resistance of the coatings.