多孔青铜过滤片的制备工艺及结构特性探究

开发一种工艺简单、重复性好、孔形孔径易控制、制取成本低的铜基多孔材料制备工艺是当前的研究热点之一.本文以青铜粉为原料,K_2CO_3为造孔剂,采用烧结溶解法制备多孔青铜过滤片,研究了造孔剂、烧结温度对样品孔隙率的影响,分析了烧结温度、压制压力对样品最大孔径和透气系数的影响,以及孔隙率与抗压强度的关系.研究结果表明:当造孔剂体积分数为20%~40%时,所制备样品的孔隙率为22.8%~44.4%,开孔孔隙率为18.5%~37.2%;随着烧结温度的升高,样品孔隙率和透气系数下降;随着压制压力增加,最大孔径和透气系数均减小;随着样品孔隙率增大,抗压强度减小.当选择造孔剂体积分数30%、压制压力150 MPa、烧结温度800℃的工艺参数下,制备出孔隙率32.2%、最大孔径4.6μm、透气系数9.27 m~3/(h·k Pa·m~2)、压缩强度27.9 MPa的多孔青铜过滤片.

Preparation process and structural characteristics of porous bronze filter

The development of preparation processing of a copper based porous material with simple procedure, excellent repeatability, easy control of pore size and low cost is one of the current research hotspots. Bronze powders were used as the raw material and K2 CO3 as pore-forming agent, the porous bronze samples were fabricated by a sintering-dissolution process. The effect of pore-forming agent and sintering temperature on the porosity of samples was studied. The effects of compacting pressure and sintering temperature on maximum pore size and permeability of samples was also examined. The relationship between porosity and compressive strength were discussed. The experimental results indicate that the whole porosity of samples is 22.8％～44. 4％, and the porosity of open pore is 18. 5％～37. 2％, for the case of 20％～40％volume fraction of pore-forming agent. Both the porosity and permeability of samples decrease with increasing the sintering temperature. Both the maximum pore size and permeability of samples decrease with increasing the compacting pressure. The compressive strength of samples decreases withincreasing porosity. The porosity, the maximum pore size, permeability, and compressive strength of porous bronze filter sample is 32. 2％, 4.6 μm, 9.27 m3/(h?kPa?m2), and 27.9 MPa, respectively at sintering temperature of 800℃, compacting pressure of 150 MPa, and the volume fraction of pore-forming agent of 30％.