振动力场对金属粉末注射熔体流变性能及相分离的影响

Effects of Vibration Force Field on Melt Rheological Properties and Phase Isolation During Metal-Powder Injection Molding

在金属粉末注射成形过程中,会出现喂料的粘结剂与金属粉末的相分离,从而影响产品密度、硬度等质量参数.为了解决这个问题,在注射成形过程中引入振动力场,将蜡基粘结剂与平均粒径为10μm的气雾化316L不锈钢粉末按各种装载量进行配比,探讨了振动频率、振幅对喂料熔体流变性能及相分离的影响.结果表明:振动力场的引入能改善金属喂料的流动性能,增加金属喂料在阿基米德螺旋模具中充模过程的流程;振幅、频率的改变能改善制品的相分离情况,频率为10Hz、振幅为0.10mm时对相分离的改善作用最为明显.

During the metal-powder injection molding, phase isolation between the binder and the metal powders often occurs, which may degrade the product quality in terms of density and hardness. In order to solve this problem, vibration force field is introduced in the molding. Based on the wax-based binder for the gas-atomized spherical 316L stainless steel powders with an average size of 10 μm, different powder-loading feedstocks are prepared, and the effects of vibration frequency and amplitude on the melt rheological properties and phase isolation are dis- cussed. Experimental results show that vibration force field helps to improve the rheological properties of melt powders and lengthen the flow length when the feedstock fills the Archimedes helical mold ; and that the variations of vibration frequency and amplitude can ameliorate the phase isolation of samples, especially at a vibration frequency of 10Hz and an amplitude of 0. 10mm.