DIE CASTING OF HIGH TEMPERATURE MATERIAL

摘要

A die casting machine (18) includes a melting unit (24), a horizontal shot sleeve (30) in fluid communication with die cavity (36) for receiving molten titanium from the melting unit (24), and a plunger (40) sealing and moveable engagement with the shot sleeve (30) for forcing molten material from the shot sleeve (30) into the die cavity (36). The melting unit (24), the shot sleeve (30) and the die cavity (36) are maintained in a non-reactive environment. The material is melted to a low superheat, e.g. less than about 200 DEG F/95 DEG C. Molten material is then transferred from the melting unit (24) to the shot sleeve (30) to fill not more than about one half of the shot sleeve volume. The molten material is injected from the sleeve (30) into the die cavity (36) using the plunger (40) for solidification in the die cavity (36). The resulting articles have a fine average grain microstructure and are characterized by an absence of flowlines.