| 摘要: | 鈦合金具有相當高的生物相容性，穩定性以及高安全性。在醫療骨科植體方面有廣泛的應用，尤其是在骨折手術中所需的骨釘、骨板以及人工骨骼等。但由於鈦合金之楊氏係數(E)與人體的骨頭有相當大的差異，而導致應力遮蔽效應(stress-shielding)造成原本的骨頭萎縮；相較於鈦合金，金屬玻璃(Metallic glass)具有較低的楊氏係數、高彈性變性回彈能力、高硬度等性質，且鈦基金屬玻璃有著出色的生物相容性、低密度以及耐腐蝕性。本研究自鈦鋯系列金屬玻璃中選擇，對人體無害之成分且具較高的玻璃形成能力的Ti42Zr35Si5Sn2.5Co12.5Ta3製作多孔材，藉由參數調整製備出符合骨性細胞長入低楊氏係數之孔隙尺寸及孔隙率。首先將Ti42Zr35Si5Sn2.5Co12.5Ta3合金利用真空旋鑄機製作出鈦基金屬玻璃薄帶，再利用SPEX震動球磨機製作出鈦基金屬玻璃粉體，最後將鈦基金屬玻璃粉體添加不同體積比例之氯化鈉於其過冷溫度區間熱壓成型，並經超音波水洗後製作出鈦基金屬玻璃多孔材，製作出不同孔隙率的鈦基金屬玻璃多孔材，尺寸可達直徑約12 mm及厚度約5 mm。
鈦基金屬玻璃多孔材在孔隙率37.8 %左右的楊氏係數與機械強度和人體骨骼較為接近；分別為楊氏係數可達至24.8 GPa且機械強度為41.4 MPa，並可以透過Gibbson和Ashby的模組，模擬出50 %孔隙率以下鈦基金屬玻璃多孔材的楊氏係數與機械強度之關係。
;Recently, Titanium base alloys have already widely used in medical applications, especially the bone nail, metal sutures, and bone implant because of its high biocompatibility, stability, and safety in human body. However, titanium alloys is much higher Young′s modulus than human bone. This leads to stress-shielding and causes atrophy of original bones (Because of the Young′s modulus mismatch, the surgery often failed due to stress-shielding.). In addition, we should be concerned about the durability, corrosion resistance and safety of Titanium alloys in human body. Compare to Titanium base alloys, Ti-based metallic glass has low Young’s modulus, excellence biocompatibility, low density, high elasticity resilience, and corrosion resistance. This research aims to make bulk metallic glass foam by using the Ti42Zr35Si5Sn2.5Co12.5Ta3 metallic glass because of its high glass forming ability and harmless to human body. At first, Ti42Zr35Si5Sn2.5Co12.5Ta3 alloy ingot was prepared by arc-melting, then re-melted and fabricated into MG ribbon by vacuum melt-spinning process. The MG ribbons were chopped and mechanical milled into MG powders by SPEX milling. Furthermore, the different volume fraction combinations of Ti-based MG powder and NaCl powder were mixed and hot-compressed in to bulk form at the supercooled temperature region of Ti-based MG. Finally, these Ti-based BMGFs with dimension of 12 mm in diameter and 4 mm in thickness were obtained by washing out the NaCl from the hot-compressed bulk samples by ultrasonic cleaning in water. Meanwhile, the results of this study show that the Ti-based BMGF with about 37.8 % porosity has similar value of Young′s modulus to human bones. |
