透气钢的制备方法及其在塑料模具中的应用研究

Development of the Breathable Steel and the Research of Its Application in the Plastic Mould

本文通过粉末粒度分级和控制粉末压制力获得具有适当孔隙率的金属粉末生坯,烧结之后获得具有连通微孔隙可以透气的粉末冶金多孔材料;向材料中渗入液体之后进行气体透过试验,气体可以顺利从材料中穿过,说明材料内部的孔隙是连通的;金相照片和SEM照片从微观上进一步证实了这种连通性;而注塑实验表明粘性的塑料并不会进入材料内的微孔隙中堵塞气体通道,注塑过程可以重复地进行;制备获得的粉末冶金多孔材料强度介于200~250MPa,可以满足透气模具钢的使用要求。

Green compact of stainless steel powder with certain porosity was obtained by controlling the compaction pressure after granularity grading. The sintered compact is a kind of porous material with tiny connective cavities. The penetration test showed that gas can smoothly flow through this material, which proves the connectivity of those cavities. The metallograph and Scanning Electron Micrograph （SEM） further proved this connective micro structure. The plastic-lnjection experiment indicated that the viscous plastic won＇t penetrate into those cavities to block the gas channels. And the plastic-injection can be repeatedly performed. This porous material has the strength between 200 -250 MPa and satisfies the requirements for the breathable mould steel.