Study On The Microstructure And Properties Of High Vanadium Alloy Cast Iron For Ultrafine Crusher Hammer

Along with the rapid development of science and technology, machinery and equipment running speed is higher and higher. While the entire operation system of the mechanical equipment has close relation with the friction and wear. The friction and wear is becoming more and more serious as the running speed of machinery and equipment to speed up, and has caused the huge losses. Such as the wear of superfine crusher hammerhead has also bring great loss. Therefore, it can reduce the wear of materials and thereby the loss through the development and use of wear resistant materials. So it is of great significance to study on the new type of the wear-resisting material and improve the comprehensive performance of the wear-resisting material.In this paper, the high vanadium alloy wear resistant cast iron with different components are prepared by the composition design, the raw material proportion,the melting and pouring and other processes. Firstly analyzes the effects of C content, W content and Mo content on hardness, impact toughness and wear resistance properties of the high vanadium alloy cast iron; Secondly, analyzes the influence of different quenching temperatures and different tempering temperatures on microstructure and wear resistance of high vanadium alloy cast iron; and determine the optimum heat treatment process. Finally the hardness, impact toughness and wear resistance and the like of the high vanadium alloy wear resistant cast iron for the optimum heat treatment were analyzed and compared with the high chromium cast iron. Microstructures of the high vanadium alloy wear resistant cast iron is analyzed by using scanning electron microscopy, the material phase composition was analyzed by using X-ray diffract meter and energy dispersive spectrometer. Rockwell hardness, impact toughness and wear resistance of the material are respectively tested by using the Rockwell hardness tester, impact tester, and friction and wear testing machine. The optimal ratio of the composition and the best heat treatment process of high vanadium alloy wear resistant cast iron are determined within the research scope of this paper by comparative analysis of the organization and the comprehensive performance and analyze the wear mechanism of high vanadium alloy cast iron.The result show that the optimal ratio of the composition of high vanadium alloy wear resistant cast iron(wt %) is Cr content of 5%, V content of 9%, C content of 3%, W content of 2%, Mo content of 0.5%. The best heat treatment is 980 quenching of 30 min and 560 ℃ ℃tempering 2h. The Phase composition of high vanadium alloy wear resistant cast iron is mainly VC particles which is synthesized in-situ and evenly distributed in the composite,(Cr,Fe)7C3 phase and Fe-Cr phase. Before heat treatment, the average Rockwell hardness is about 63.7 HRC, the average impact toughness is 8.9 J/cm2, the wear resistance is enhanced over 1 times than the high chromium cast iron. After heat treatment, the average Rockwell hardness is about 61.8HRC, the average impact toughness is 11.3J/cm2, the wear resistance is enhanced over 2 times than high chromium cast iron.