Eeffects of die casting conditions on the mechanical properties of ADC 12

Abstract

The object of this study was to know the effects of various die casting conditions such as injection pressure, locking force, injection speed, sleeve temperature, chill period, molten metal temperature, automatically controlled mold temperature, and injection speed ratio on the mechanical properties of ADC12 alloy products (ASTM E8 test bar). The die casting machine used in our laboratory was of DC 250 type, which can record the measuring results of the above casting conditions and also can control the mold temperature. The results obtained were as follows:1. Injection pressure and locking force gave almost no effects on the mechanical properties of ASTM test bar.2. Mechanical properties decayed at extremely high or low injection speed, but they were improved with the increase of injection speed, because the pressure increased immediately after filling molten metal into the cavity, whereby beneficial effects were given on the strength of the products.3. Higher casting temperature (680°C) was recommended for better mechanical properties from the viewpoints of fluidity and castability of molten metal.4. Mechanical properties decayed with the elevation of mold temperature.5. They were the best at the injection speed ratio of 1 to 1.6. Mechanical properties of ASTM test bar, were independent of the chill period of 5-10 seconds.