粉末形状与松装密度对不锈钢烧结多孔材料制备工艺及其性能的影响

通过选用气雾化及水雾化两种工艺方法制备的不锈钢粉末来制取粉末烧结多孔材料。探讨了粉末形状及松装密度对不锈钢粉末烧结多孔材料制造工艺中的成形压力和烧结温度等工艺参数的影响;研究了原料粉末松装密度对不锈钢粉末烧结多孔材料的透气性、拉伸强度的影响。结果表明:成形压力、烧结温度和制品的透气性受粉末松装密度影响显著。粒度范围为0.18～0.90mm时,气雾化粉末的成形压力比水雾化粉末要高近1倍;当粉末的粒度相同时,采用松装密度大的球形粉末所需的烧结温度比松装密度小的不规则粉末的高60～70℃;粒度为0.45～0.60mm时,选用松装密度为4.13 g/cm3粉末所制备的多孔制品的透气性为3.16×10-10m2,而选用松装密度为2.67 g/cm3的粉末所制备的多孔制品的透气性仅为8.8×10-11m2。不锈钢多孔材料的强度受原料粉末的松装密度影响显著;粒度相同,制备工艺相同时,采用较低松装密度的粉末的制品,能够得到较高的强度。

Effect of apparent density of powder and shape of the particle on preparation and properties of sintered stainless steel porous material

Porous sintered powder materials were prepared by using gas atomized and water atomized stainless steel powders with different particle shape.The effects of particle shape and powder apparent density on the forming pressure and sintering temperature etc.In the manufacturing process of sintered stainless steel porous materials were studied.The effects of powder apparent density of raw material on permeability and tensile strength of stainless steel powder sintered porous material were studied.Results show that the powder apparent density markedly affects forming pressure,sintering temperature and permeability of the products.The forming pressure of gas atomized powder is higher than that of water atomized powder by near one time in the particle size range of 0.18-0.90mm.The sintering temperature of spherical powder is higher than that of irregular powder by 60-70℃ in the same particle size range.In the particle size range of 0.45-0.60mm,the product permeability made of powder with apparent density of 4.13 g/cm3 is 3.16×10-10m2,while that of powder with apparent density of 2.67 g/cm3 is only 8.8×10-11m2.The strength of sintered porous material of stainless steel powder is affected markedly by the powder apparent density,the apparent density the higher,the strength the lower under the same conditions.