【摘要】 通过"钨薄板—灰口铸铁复合原位反应"工艺,制备出表面WC致密陶瓷复合材料,分别采用SEM、XRD、HDX-1000、ML-100对表面陶瓷微观组织、物相组成、显微硬度及相对耐磨性进行了研究。研究表明:表面WC致密陶瓷层中,WC尺寸为20~40μm,体积分数达到90%以上,致密WC晶粒间组织为珠光体,并呈粒状或长细片状结构分布。其中,在表面WC致密陶瓷层中,WC以两种形态存在:大块状WC致密陶瓷颗粒和长条状WC致密陶瓷颗粒。磨损试验选择320目石英砂纸磨料、分别在5 N、10N、15 N、20 N载荷作用下,表面大块状WC致密陶瓷层的相对耐磨性分别为灰口铸铁的186、112、83和30.2倍。由此说明,在低、中、高载荷下,随着载荷的增加,其相对耐磨性逐渐降低,表面大块状WC致密陶瓷颗粒的磨损方式主要为划痕、颗粒破碎、颗粒剥落等。更多还原

【Abstract】 The WC / Fe surface gradient composite was prepared by in-situ reaction synthesis with tungsten sheet and gray cast iron. The micro-structure,phase composition,micro-hardness and the wear resistance of the WC ceramics layer of the composite were analyzed by SEM,XRD,mirco-hardness measurement and wear test. The result shows that the size of WC particulates is 20-40 μm in the WC surface layer of the composite with the volume fraction of WC particulate exceeding 90% and the microstructure of the matrix is pearlite. Bulk and strip WC particulates are observed in the WC reinforced surface layer. Different morphology tungsten carbide has different hardness. The relative wear resistance of the WC / Fe surface gradient composite increases by 30. 2 times to 186 times compared with that of gray cast iron under different loads. The main wear mechanisms of the composite are scratches,plough,particulates breakage and exfoliation.更多还原