不同粉末粒度的粉末轧制多孔钛板的孔隙性能研究

为满足湿法冶金、氯碱、水处理、制药等行业对多孔钛板过滤元件的需求,以粉末轧制法制备多孔钛板为出发点,开展了满足轧制工艺要求的多孔钛板粉末轧制、烧结、性能测试等研究。通过对不同性能的钛粉进行粉末轧制、真空烧结,制得了宽度为420 mm、厚度不同、组织均匀的多孔钛板,研究了不同粉末性能对其孔隙度、最大孔径和透气度的影响。结果表明:随着粉末粒度的减小,多孔钛板的密度有所增大,孔隙度、最大孔径和透气度逐渐减小。其中,多孔钛板最大孔径和透气度的变化规律与模压多孔材料的相同。在追求孔隙度最大化时,以最小的轧制压力轧制成型多孔钛板,粉末粒度越大,其厚度越大。当粉末粒度相同时,多孔钛板厚度越大,其内部孔道路径越长,孔结构越复杂,气体在透过多孔结构通道时所消耗的能量也越多,透气度则越低。

Study on the Pore Properties of the Powder-Rolled Porous Ti Sheets with Different Powder Sizes

The porous titanium(Ti)sheets as filter elements exhibit a great demand in the field of hydro-metallurgy process,chlor-alkail industry,water treatment,pharmaceutical industry,etc.For the powder-rolled porous Ti sheets,systematical studies had been carried out on rolling,sintering process and properties of porous Ti sheets.In this work,porous Ti sheets with the width of 420 mm,different thicknesses and uniform microstructure were fabricated by powder rolling combining with vacuum sintering.The effect of powder properties on the performance of powder-rolled porous Ti sheets,including porosity,maximum pore size,gas permeability,had been investigated.The results indicate that with the decrease of powder size,the density of porous Ti sheet increases,while its porosity,maximum pore size and gas permeability decrease.Moreover,the variation rule of maximum pore size and gas permeability to porous Ti steel is similar to that of molded porous materials.Therefore,in order to obtain the maximum porosity,porous Ti sheets should be rolled with the minimum rolling force.At that time,the coarser powders are,the thicker porous Ti sheets are.With the same powder size,the internal pore path of porous Ti sheet became longer and more complicated via its thickness increasing.It makes more energy consumed by gas passing through the pore structure,finally resulting in poor gas permeability of porous Ti sheet.