Study On Preparation Technology And Properties Of Zn-Cu-Ti Alloy Plate

The modified Zn-Cu-Ti alloy is a creep resistant,corrosion resistant alloy,its mechanical properties can be comparable with the Cu alloy.Production of Zn-Cu-Ti alloy plate in Chinese has not been developed,however,it already has a huge market demand and practical application,and our current Zn-Cu-Ti plate mainly come from imports.In this topic,self-designed master alloys and refining agent were used to cast the alloy,and Zn-Cu-Ti alloy plate was prepared by rolling deformation.The rolling process,creep property,annealing recrystallization behavior,corrosion resistance and mechanism of the alloy plate were mainly studied.At the same time,the feasibility of ZnS coating on the alloy plate was studied.By comparing the microstructures,tensile properties at room and high temperature,creep properties and fracture analysis of the as-cast metal and alloy in the different rolling processes,it was found that the elongated second phase of the Zn-1.0Cu-0.1Ti alloy was crushed into nanometer-scale circular particles after rolling,and when the rolling temperature was 250℃ and the strain was 20³0%,we could obtain the best mechanical properties.The creep experiment was carried out and the creep equation of Zn-1.0Cu-0.1Ti alloy sheet was established:e（28）0.54s^4.33e^-10357.2/RT.The creep mechanism is mainly dislocation climbing mechanism,accompanied by grain boundary slip mechanism and atom diffusion mechanism.The recrystallization temperature of the alloy is about 210℃,and the aging treatment has little effect on the hardness of the alloy.At 210²70℃,the recrystallization grain growth model of the alloy can be expressed as D²（28）4.563′10^{-1 0}（10）2.975′10^-8e^-5615.8/T.After immersion corrosion,the results show that the corrosion rate can be affected by the temperature,which can change the bonding mode of the corrosion product and the Zn matrix.The order of the corrosion rate in different media is:tap water<3%NaCl solution<3%NaCl+1%Na₂SO₄ solution;With the increase of the corrosion time,the surface of the alloy will spontaneously form a dense protective layer,and the corrosion rate will decrease gradually.Mg can improve the corrosion resistance of the alloy by over 20%.The ZnS was synthesized by hydrothermal method using ZnCl₂ and SC（NH₂）₂ as zinc and sulfur sources,hydrazine hydrate as complexing agent,and experimentally prepared ZnS powders were cubic zinc sulfide（β-ZnS）;The rate of ZnS coatings corrosion and hydrolysis in three different media was tap water<3%NaCl+1%Na₂SO₄ mixed solution<3%NaCl solution,which S^2-hydrolysis releasing HS^-and H₂S and then oxidation to SO₄^2-in the photocatalytic was the dominant factor of corrosion.