Date of Award
Committee Member 1
Committee Member 2
Shot sleeve is a very easily worn out part in a high-pressure die-casting machine due to serious dissolution of the area underneath the pouring hole. It is because during a normal pouring process, the high temperature molten aluminum will impact and dissolve that area of the shot sleeve by complex chemical and physical process. Rotation experiment was carried out to H13 and four kinds of refractory metal samples. SEM and EDS pictures were taken in order to investigate the microstructure and the dissolution mechanism of these materials. This suggests a high strength niobium is an ideal material for that area of a shot sleeve. Comparison among the tested samples were conducted to suggest a better material than H13 for shot sleeve. The result shows that niobium is the best dissolution resistance material in all the tested materials. Titanium is the worst one in all the refractory materials though, it is still 9 times better than H13. A three-stage dissolution theory is proposed including reaction, washout and diffusion stage. The washout and diffusion stage are when the weight loss occurred significantly. This study gives reference and indication for improving shot tooling as well as a way to understand the dissolution process of metals in molten aluminum. Future study is suggested to be performed in a real die-casting environment.
Zhu, Hengyu, "Dissolution Rate And Mechanism Of Metals In Molten Aluminum Alloy A380" (2014). Open Access Theses. 465.