Experimental study and numerical simulation of the influence of ball milling parameters on granule sizes of mold powder

In this study, the ball milling parameters (solids loading, binder and dispersant content, ball milling time) were optimized to control the granule size of the mold powder during spray drying and obtain good mechanical strength and metallurgical properties of the hollow granule mold powder. The effect of ball milling parameters on the granule size of mold powder was systematically investigated using computational fluid dynamics (CFD). A series of parameters, such as the temperature field, velocity field, granule size and trajectory were varied and the moisture content of the slurry in the spray drying tower was computed. To ensure that the granule size of the mold powder is controlled at 0.2-0.6 mm, the following optimum ball milling parameters were chosen based on the results of the numerical simulation: solid loading, 60 wt%; modified sodium carboxymethyl cellulose binder content, 1.0 wt%; sodium tripolyphosphate dispersant content, 0.5 wt%; ball-milling time, 60 min.