Research On Microstructure And Properties Of The Iron Substrate Resistant Composite Materials

The processing of particle reinforced iron matrix composites was one of the effective methods to improve the surface resistance of castings. Cast infiltration process has been used to botain composite layer of local surface wear-resistant. This process was simple operation, cost saving, etc.In this paper, wear resistance of the high chromium cast iron surface composite matirals enhanced by SiC and WC particle was studied. The effect of grain size of SiC and WC, and addition of binder on the microstructures and properties of iron substrate composite material have been discussed, and the effect of SiC and WC grain size on cast-penetrated was systematically analysed.The results showed that the size of SiC, WC particles has a great influence on the microstructure and mechanical properties of composite materials. Under the condition of this experiment, admirable composite layer of the four series of Si C alcohol-based coating and the three series of WC alcohol-based coatings were formed on the block surface. The thickness of the composite layer was around 3mm.Unmelted SiC and WC particles were detected in the SiC and WC block composite layer respectively via microstructure observation and X-ray diffraction analysis. Due to the effect of high temperature of the liquid metal, some new enhancements phases such as FeSiC、Fe8Si2C、Cr22.23Fe0.77C6 and Fe6W6C、C0.055Fe1.943、W2C、Fe7W6 were formated in composite coating.Results show that hardness of the SiC series block has the highest increased 3.03 times. The alloy coating formula is: SiC(70 ~ 80 mesh) 14 ml, chromium iron powder(100 mesh) 7 ml, EPS 4 ml, binder 1.6 ml; hardness of the WC series block has the highest increased 3.14 times, The alloy coating formula is: WC(60 ~ 80 mesh) 14 ml, chromium iron powder(100 mesh) 7 ml, EPS 4 ml, binder 1.2 ml.In this paper, the wear resistance of the composite coating with SiC(70~80 mesh)increased by 1.88 times while the wear resistance of the composite coating with WC(60~80 mesh)increased by 2.44 times.