表面活性剂对MIM316L不锈钢粉末制备性能的影响

Effect of surfactants on preparation and performance of MIM 316L stainless steel powder

采用高压水气联合雾化工艺,在雾化水中加入适量表面活性剂,制备了MIM用超细316L不锈钢粉末,研究了表面活性剂对粉末雾化制备的影响。结果表明:表面活性剂的加入会一定程度地影响粉末的振实密度、粒径和粒度分布及表面形貌等。其中,十二烷基硫酸钠(SDS)能有效降低粉末颗粒粒径和提高振实密度,当SDS用量为1%(质量分数)时,粉末颗粒的中位径由10.33μm降低到8.76μm,振实密度可由4.16 g/cm3提高到4.65 g/cm3,且得到的不锈钢粉末分散均匀,颗粒表面光滑且呈类球形。粉末制成喂料,经注射成形及脱脂烧结后,样品指标均达到美国MPIF标准,当烧结温度为1 380℃时,烧结密度和硬度分别为7.85 g/cm3、70 HRB。经此工艺制得的316L不锈钢粉末,性能达到国内先进水平。

Superfine MIM 316L stainless steel powder was prepared by high-pressure water and gas joint atomization process adding an appropriate amount of a surfactant in the atomization water. The effect of surfactants on the preparation of atomized powder was studied. The results show that the tap density , particle size and particle size distribution and surface morphology of the powder will be affected to some extent due to the addition of a surface active agent . Among them, sodium dodecyl sulfate （SDS） can effectively reduce the powder particle size and improve tap density, when SDS addition amount of 1 wt% , the median diameter of the powder particle reduce from 10.33 μm to 8.76 μm, and powder tap density increased from 4.16 g/cm^3 to 4.65 g/cm^3, moreover, the resulting in like spherical stainless steel powder particles with uniform dispersion and smooth surface. The index of the samples after injection molding , degreasing and sintering reach MPIF standard, when the sintering temperature is 1 380℃ , the sintered density and hardness is 7.85 g/cm^3 and 70 HRB respectively. The performance of the 316L stainless steel powder reach advanced level at home.