Effect of Different Titanium Alloying Methods on the Grain Refinement and Mechanical Properties of ZA46 Alloy

Three kinds of titanium alloying methods including low-titanium aluminum alloy addition, aluminum-titanium master alloy addition and villiaumite addition were chosen. The influences of titanium alloying methods on the microstructure and the mechanical property of Zn-Al alloy were studied. The test results show that it is effective for grain refining of Zn-Al alloy by adding titanium to the melt before casting. The low-titanium alloys addition is the most effective for grain refining of the Zn-Al alloy. The reason might be attributed to that the titanium atoms evenly spread to the whole melt rapidly under stirring action of electromagnetic field and, the better capacity of the heterogeneous nucleation of in-situ precipitating heterogeneous nucleation sites. The finer grain size increases the grain boundary areas and it causes that the grain boundary has better ability to prohibit dislocation passing through. Thus, the binding ability of the base is strengthened. The test alloy added by low-titanium aluminum alloy shows the highest tensile properties and wear resistance.