| Based on the requirements of sandblasting nozzles, B4C based advanced ceramic nozzles have been successfully developed. Researches were carried out on its composition and hot-pressing parameters, mechanical properties and microstructure. With the theory of gas-solid two-phase flow, computer simulation of sandblasting process was discussed. Under the experimental results, effect of the factors that influence the nozzle wear was investigated, the erosion wear model was established, and the wear mechanisms were studied.B4C/(W,Ti)C ceramic composites with different content of solid-solution (W,Ti)C were produced by hot pressing. Chemical reaction took place for this ceramic system during hot pressing sintering, and resulted in a B4C/TiB2A/W2B5 composite. The flexure strength and fracture toughness were increased from 300 MPa and 2.5 MPa.m1/2 for monolithic B4C to 693 MPa and 3.9 MPa.m1/2for B4C/(W,Ti)C composites respectively, while the sintering temperature was lowered from 2200℃ to 1850℃.The density, flexure strength and fracture toughness of B4C/(W,Ti)C ceramic composites continuously increased with increasing (W,Ti)C content, while the hardness decreased with increasing (W,Ti)C content. There are a lot of obvious pores located at the B4C grain boundary, and the grain size is about 6-8 urn. While there are almost no pores observed in the composite and the grain size is less than 2 μm.Erosion wear behavior of the nozzles made from different materials has been studied. Results showed that the wear resistance of the nozzles from high to low is B4C, B4C/(W,Ti)C, Al2O3/(W,Ti)C, 75 ceramic, YG8, YT15,45# steel, 45# hardened steel, cast iron(HT 15-33) and polyurethane plastic in turn, and B4C/(W,Ti)C ceramic nozzle has high ratio of capability to price among all of these nozzles.The effect of abrasive particle hardness(Hp), the ratio of particle hardness to nozzle...
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