粉末冶金多孔钛的研究

采用粉末冶金法在10-3Pa的真空度下烧结多孔钛,获得开孔隙度<50%,孔径分布在5～50μm之间的多孔钛 借助金相显微观察孔隙形貌、利用数理统计方法确定孔径分布、进行压缩试验测定压缩性能 分析了原始粉末的粒度、成型压力、烧结制度对多孔钛的孔隙度、孔径及压缩性能的影响规律 实验结果表明:多孔钛的孔隙度及开孔隙度都随成型压力的增大、烧结温度的升高和烧结时间的延长而降低;孔隙的尺寸随粉末粒度的增大、烧结温度的降低而增大;成型压力增大和烧结时间的延长对孔隙尺寸的影响表现在小孔径孔隙的比例增大,而大孔径孔隙的比例降低;但是粉末粒度变化对多孔钛孔隙度、孔隙尺寸的影响要比成型压力、烧结温度和烧结时间变化的影响强烈的多;多孔钛的开孔隙度越大,其压缩强度越低;当多孔钛的开孔隙度由16%增大至44%时,其断裂强度由0.75GPa降至0.18Gpa

Study of Porous Ti by Powder Metallurgy

Porous Ti is prepared by powder metallurgy route, and the effects of particle size of the Ti powder on the total and open porosities and pore size are studied. The distribution of the pore size is ascertained by means of quantitative metallurgy under optical microscope, and the compressive property of the porous Ti is measured by compression test. Whereas, the effects of the sintering parameters are also analyzed. Experimental results show that the total and open porosities are reduced with the increase in particle size and the decrease in sintering temperature. The increase in the shaping pressure and sintering time results in an increase in the prorortion of the fine pores. However, the particle size affects the porosity and pore size more significantly than shaping pressure and sintering temperature and time. The larger the open porosity, the less the compressive strength is of the porous Ti.