| In this paper,ZA35-3.5Mn alloy is formed by spray deposition.The microstructure of the alloy under different squeezed parameters was studied,a better squeezing parameter that is temperature 260℃ratio 21.7 could be obtained with applying direct analysis.The results indicate that at the same squeezed temperature,when squeezed ratio is increased,the tensile strength,hardness and elongation of alloy are increased quickly, when ratio becomes 21,the best mechanical property is obtained,but increasing the ratio to 33.8,the mechanical property is decreased;at the same squeezed ratio,with the squeezed temperature increased,the tensile strength,hardness and elongation of alloy is decreased. the mechanical property of alloy by temperature 260℃ratio 21.7 at room temperature is the best,that tensile strength is 491.2 MPa,elongation is 5.19%,hardness is 151 HBS.According to the analysis on the microstructure,the results show that the phase compositions of ZA35-3.SMn alloy by temperature 260℃areα-Al,η-Zn,Mg32(AlZn)19, Al11Cu5Mn3,MnAl6,CuMnZn;when temperature increases to 380℃,phase CuZn6 is generated.With ratio increases,the grains can be refined,initial phases tum from rough grains into uniformly distributed fine ones;the pore space is fade;But using overtop ratio, the grains grow rapidly,phases are aggregated and distributed of concentrated.To compare with alloy squeezed at 320℃,the friction coefficient of alloy squeezed at 260℃reduces to 16.69%at the same rotation speed.When applying load is the same, the friction coefficient of alloy squeezed at 260℃reduces to 17.37%.Mn phase as hard phase can bear heavier load,which makes ZA35-3.5Mn alloy by spray deposition having better wear and friction properties.While exposed at 150℃,the strength of alloy at 260℃ratio 21.7 is enhanced and Cu,Mn in the alloy are precipitated as MnZnAl3 and CuAl;and while exposed at 200℃, the strength of the alloy is reduced,Cu,Mn are rapidly precipitated in the formation of phase MnCuAlZn and MnCuAlMgZn.
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