WC_p/Mn13表面复合材料的制备及其冲击磨损性能

Fabrication and Impact Wear Resistance of WC_p/Mn13 Surface Composites

为了克服高锰钢Mn13在中低应力条件下冲击磨损性能差的问题,利用离心铸造法制备了WCp/Mn13表面复合材料,通过扫描电镜、能谱、X射线衍射等手段研究了WC陶瓷颗粒与Mn13基体的界面结构,并用不同粒径的WC颗粒复合材料与高锰钢进行了冲击磨损对比试验.研究结果表明WC与基体形成了一定厚度的扩散层,扩散层中有细小复合碳化物析出,WC与基体间的结合为冶金结合;小颗粒WC增强复合材料的抗冲击磨损性能优于高锰钢,而大颗粒WC增强的复合材料在冲击载荷较小时,抗冲击磨损性能优于高锰钢,当冲击载荷较大时,抗冲击磨损性能不如高锰钢,因此在冲击磨损工况下,应当选择颗粒尺寸适当的WC颗粒增强高锰钢.

To improve the impact wear resistance of high manganese steel (Mn13), a new kind of surface composite WCp/Mn13 was fabricated by means of centrifugal casting. The interfacial structure between WC and matrix was analyzed by scanning electron microscope (SEM), energy dispersive X-ray detector (EDX) and X-ray diffraction (XRD). The impact wear tests of three kinds of composites with different WC particle sizes were carried out under different impact loads, and the wear tests of Mn13 were comparatively carried out under the same conditions. The results show that WC particles are partially dissolved into the liquid steel during centrifugal casting, and many fine carbides precipitate around the former WC particles during subsequent cooling; thus the interface between WC particles and the matrix is a perfect metallurgical combination. The composites reinforced with smaller WC particles demonstrate better impact wear resistance than that of Mn13. The composites reinforced with larger WC particles show superior impact wear resistance than that of Mn13 as the impact load is low, and show poorer impact wear resistance as the impact load is high. It is necessary to choose suitable WC particles for making Mn13 matrix composites according to service conditions.