| Zn and Zn-based alloys with lower melting point, little realsing heat when melte, good anti friction performance, good process performance, good fluidity and coating properties, a series of advantages and rich resources, easy recovery and so on, have a wide application prospect in thermal spraying, surface modification of capacitors, hardware accessories, appliances, electronics, industrial equipments and automotive industries. After the thermal deformation processing of zinc alloy material, organizational structure significantly refined, and the mechanical properties compared with the cast been significantly improved.The data about Zn4A10.1Ti alloy testing was gotten by isothermal compression testing method with thermal simulator. The flow stress behavior and microstructure evolution behavior for Zn4A10.1Ti alloy were studied, and choose the peak flow stress under different deformation conditions to establish a constitutive equation. The interdependences of flow stress σ, strain rate ε and deformation T for the alloy have been studied with the aids of regression analysis and OM. The proeessing map of Zn4A10.1 Ti zinc alloy was established, which based on dynamic materials model.When the strain is 0.3, combined with metallographic organization, to study the processing map in the different area.The main conclusions are as follows:(1) The main effect of hot deformation parameters (deformation temperature, strain rate) of Zn4A10.1Ti alloy rheological stress influence rule. At a constant strain rate, with the increase of deformation temperature on flow stress decreased significantly; at the same deformation temperature, with increasing strain rate reduced the flow stress.(2) By using the method of linear regression of Zn4A10.1Ti alloy during plastic deformation at elevated temperature was determined, the peakfiow stress σ, should meet the hyperbolic sine function relationship between the strain rate and deformation temperature of T, and the temperature compensation should be constitutive equation of variable rate Zener-Hollmon parameter to describe the corresponding to the peak stress(3) The microstructure evolution of Zn4A10.1Ti zinc alloy during hot deformation is revealed. The results indicate that both increasing deformation temperature and decreasing strain rate are helped to the dynamic recrystallization phenomenon.(4) After analyzing the proeessing map of Zn4A0.1Ti zinc alloy, the results demonstrate that the strain has little influence on proeessing map of Zn4A10.1Ti zinc alloy. When the strain is 0.3, Low temperature and high strain rate zone temperature 230℃～260℃ strain rate 1s-1～10s-1) and Medium temperature and lower strain rate zone (temperature 260℃～290℃ strain rate 0.01s-1～0.1s-1) are rheological instability region. In the actual processing of deformation, we should try to avoid these two regions. Medium temperature and high strain rate region (temperature 260℃～290℃ 、strain rate 1s-1～10s-1) is the best region of Zn4A10.1Ti zinc alloy.CASTEX as a technique for the production of high efficiency, low cost, short process, in the production of zinc alloy wire rod rarely reported. After CASTEX shearing squeeze casting wheel rotation, the grain refinement to some extent, the mechanical properties of tissue may be raised. Experiments on Zn4A10.1Ti zinc alloy extrusion forming process continuous casting process parameters were optimized. Experimental results show that:Other process parameters at the same premise, when given with a length of 7mm diameter, the better the overall performance CASTEX Zn4A10.1Ti zinc alloys.Experiments on different alloy components (Zn4Al and Zn4A10.1Ti) zinc alloy was studied in the microstructure and properties of the same cast extrusion process conditions of products. The Ti in the organization to exist in the form of Al3Ti, solid solution in Zn4Al eutectic (condensate) body,compared with the Zn4Al alloy, the microstructure of Zn4A10.1Ti alloy was refined, more excellent mechanical properties. |
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