鈦金屬具優良生物相容性、抗腐蝕性以及比強度，在牙科應用十分普及。
雖然鈦金屬具優良生物相容性以及材料強度，但鈦金屬於鑄造時的高熔點以及高溫時的高反應性，使傳統包埋材多在鑄造過程中容易與鈦發生反應，導致最終鑄件性質發生改變或精密度不佳。因此，開發適用於鈦金屬鑄造之包埋材已成為研究之重點。
本研究基於基材A之包埋材性質進行改善，藉由調整基材A、基材B、添加劑D、添加劑F添加量以及燒結參數，使包埋材硬化時間減少，膨脹率提升。此外，添加添加劑G作為抗氧化劑，觀察添加劑G的添加是否能減少鈦金屬鑄造後氧化的情形，期望能提供未來包埋材研究開發之參考。

The research is divided into two parts. For the first part, our goal is to shorten the setting time and increase the expansion ratio. Second part is to decrease the oxidation of casting. We adjusted the wt% of B in order to increase the production of spinel, which is used to increase the expansion ratio. And we adjusted the wt% of D to shorten the setting time. Then we added G, looking forward to decrease the oxidation of casting. Results of first part showed that, with increasing wt% of B, the fluidity is 175mm - 201mm, setting time 17min - 22min, before sintered compressive strength 5.45 MPa - 31.2 MPa, after sintered compressive strength 10.79 MPa - 30.21 MPa and expansion ratio 0.81% - 1.68%. Besides, increasing D effectively shortened setting time. For the second part, by adding G, we observed that it reduced expansion ratio. Then we used investment material which contains q wt% - u wt% of G for casting. The results showed that r wt% of G has the largest area of golden oxide layer. The final component results fluidity 158mm, setting time 8min, before sintered strength 19.59 MPa, after sintered compressive strength 16.9 MPa and expansion ratio 1.16%.

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