| Nonferrous metals and its alloys are essential basic materials and important strategic materials to the development of national economy, the defense industry and science and technology. Zinc-aluminum alloy is one of the most widely used non-ferrous alloys, which play an extremely important role in industrial production. But alloy castings produced by conventional methods often present coarse solidification microstructure and show poor mechanical properties and wear resistance and other issues, which has seriously affected the application of the alloy. SiC particle is an ideal reinforcement and it has many properties of high strength, high hardness, high modulus, and low coefficient of expansion. Solidification parameter is also an important factor affect the solidification microstructures.This paper studied the toughening of zinc-aluminum alloy modified by nano powder,and discussed how did the powder dosage, coagulation parameters affect the solidification structure and the effects of abrasion.This paper also preliminary discussed abrasion mechanism of zinc-aluminum alloy,and made wearable experiment of brass and bronze. Compare toughening zinc alloy, brass and bronze wear resistance to analyze its economic benefits.With the increase of modified SiC nanoparticles, the microstructures were refined and mechanical properties of ZA27and ZA12zinc alloys were enhanced continuously. When the addition was over0.1%, the refinement of microstructures and the increase of mechanical properties were not obvious. It was harmful for ZA27and ZA12zinc alloys to increase the addition temperature and holding time and casting temperature of modified nano-SiC powder. For ZA27zinc alloy, when the addition of modified SiC nanoparticles was0.05%, the addition temperature was680℃, the holding time was3minutes, and the casting temperature was600℃, the microstructure and mechanical properties were better. For ZA12zinc alloy, when the addition of modified nano-SiC powder was0.05%, the addition temperature was580℃, and the holding time was3minutes, the casting temperature was500℃, the microstructure and mechanical properties were better.With the modified nano-SiC particles added, the wear resistance of zinc alloy ZA27and ZA12has increased. Make comparison between ZA27alloy toughened by modified nano-SiC powder and normal ZA27zinc alloy, wear resistance of the former was increased by30%. ZA12alloy toughened by nano-SiC powder contrast common ZA12zinc alloy,wear resistance has increased by33%. Wear resistance of ZA27alloy toughened by nano-SiC powder was more than82%of H62brass alloy and wear resistance of ZA27alloy toughened by modified nano-SiC powder was more than71%of H62brass alloy; Wear resistance of ZA27alloy toughened by nano-SiC powder is80%of resistant materials ZCuSn5Pb5Zn5tin bronze and Wear resistance of ZA12alloy toughened by nano-SiC powder is24%of resistant materials ZCuSn5Pb5Zn5tin bronze.From the analysis of the cost, copper is very expensive metallic materials.The costs of Zinc alloy thoughened by modified nano-SiC powder was reduced by55%compared to H62brass alloy,while the wear resistance was higher than H62brass alloy. The costs of Zinc alloy thoughened by modified nano-SiC powder was reduced by68%compared to H62brass alloy,while the wear resistance was almost equal to that of H62brass alloy. |
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