EFFECT OF INJECTION PARAMETERS AND CAVITY POSITION ON MIM GREEN PART MASS
This paper presents effect of the cavity position on green mass of metal injection (MIM) parts molded in a four-cavity split mold for different values of injection velocity, holding pressure profile and mold temperature. Test components where ring-shaped containing an external groove at the middle of height. It was found that the parameters that have greatest influence on part mass in single cavity are mold temperature folowed by holding pressure and injection velocity. Obtained experimental results also addres that the main source of variation in verticaly positioned runner system becomes cavity to cavity variation. In this case cavity to cavity variation increase is caused by separation and segregation supported by gravity effect.It was also found that in binder rich upper-cavity zone at sufficiently low mold temperature packing pressure increase cause decreasing of green part mass due to shift of glass transition temperature toward higher values.