Abstract
Keywords: Die-casting, Visualization, Molten metal flow, Air leak, CAE
Die-casting is one of the most excellent casting processes in the point of high productivity and the process compaction. On the other hand, the control of the molten metal is very difficult because the filling and solidification of that is remarkably fast. As a result, die-casting is at great risk of generating defects inside of products. Therefore, in most of production spots, they remove air in the die with vacuum pump through the vent hole before filling of molten metal (what is called, vacuum die-casting process) and improve the quality of casting products. However, because it is difficult to achieve the complete sealing of complicated parts of die-casting machine or die cavity (for example, the clearance between sleeve and plunger chip, parting line of die, and so on), air leak with the vacuum occurs in such a part. And it is expected that the leak (especially at the clearance between sleeve and plunger chip) have some kind of influence on behaviour of molten metal in the die cavity and the quality of products. In this study, we observed phenomena, what we would call 'precedent metal influx', occurred in that part by using the visualization system utilizing X-ray and non-contact molten metal sensor utilizing eddy current and clarified the influence that it gave quality. And then, we formulated new physical model based on that phenomenon to improve the precision of casting CAE.