| The microstructure and properties of W-Ti alloys as sputtering targets have become a hot research due to the extensive application of W-Ti film.Studies have shown that the microstructure and properties of W-Ti alloys determines the properties of the sputtered film.A good properties of W-Ti alloy are obtained by the traditional methods with a complicated sintering process,which is not conducive to product.So it become the study focus of the current W-Ti alloy to look for a new preparation method with a good balance between microstructure and properties of W-Ti alloys and simplify sintering process.In this study,the W-Ti alloy were prepared by a combination of energy ball milling process and different sintering,the influence of sintering process,sintering temperature,Ti content and W powder particle size on microstructure and properties of W-Ti alloy were investigated,and the diffusion mechanism based on interdiffusion coefficient of alloy during sintered process was discussed.The following conclusions were obtained:Through high-energy ball milling,surface defect,the microscopic strain were increased as well,providing a theoretical possibility for promoting the diffusion of Ti to W.Under this experimental conditions,vacuum sintering,hot press sintering and spark plasma sintering(SPS)were respectively discussed.W-10Ti alloy prepared by hot press sintering has the best microstructure and properties.Although the microstructure and properties of alloy sintered by SPS are slightly less than that of hot press sintering,the sintering time of SPS is shorter,the interdiffusion coefficient is higher,and the microstructure and properties of alloy has a large room for improvement,so it is a promising new method to prepare W-Ti alloy.W-10Ti alloy samples are respectively prepared by SPS system at 1300?,1400?,1500?.The results incidate that the higher SPS temperature is,the better alloy microstructure and properties are.The W-10Ti alloy prepared at 1500?has less Ti-rich phase,small and uniform microstructure can be obtained as well,with a good properties such as the density,conductivity and hardness etc.The W-5Ti,W-10Ti and W-15Ti alloy samples were prepared by SPS system at 1400?.With the increasing of the Ti content,the density of the alloy gradually increased,however,the Ti-rich phase content in W-Ti alloy dramatically increased,thus leading to the properties of W-Ti alloy such as conductivity,hardness and elastic modulus increase and then decrease,when Ti content is 10 wt%is optimal.In the process of SPS,the larger gap existed between micrometer(8?m)W powder,which is in favor of the formation of the plasma,as a result,promoting the sintering process of the alloy,so the microstructure and properties of W-10Ti alloy prepared by micrometer W powder were better than that of prepared by sub micrometer W powder(0.4?m and 0.8?m).The density is 92.8%,conductivity is 4.9S/m,hardness is 843.4HV0.1,elastic modulus is 273.1 GPa and fracture toughness is 10.34MPa·m1/2. |
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