鎂合金擁有低的密度以及較高的比強度的優點，但是，其低剛性、加工性差以及較低的抗腐蝕性，造成應用受到限制。本研究選用Mg58Cu31Gd11為基材，利用外添加25 vol.% 的多孔鉬顆粒製成鎂基複材，將鋯基((Zr53Cu30Ni9Al8)99.5Si0.5)金屬玻璃薄膜鍍覆在鎂基複材表面來改善機械性質與抗腐蝕性，並利用三點彎曲進行抗彎強度提升之探討。分別以鋁-鈦(25 nm / 25 nm)與銅(50 nm)作為基材與鍍膜間的緩衝層，根據膠帶附著力測試結果顯示，以鋁-鈦為緩衝層所鍍覆之鋯基金屬玻璃薄膜之附著力(4 B)優於以銅為緩衝層的薄膜之附著力(0 B)。鎂基塊狀金屬玻璃基材與複材於抗彎試驗後，可觀察到多孔鉬顆粒於鎂基塊狀金屬玻璃複材內，可以有效的阻擋裂縫的傳播以及吸收掉裂縫的能量，促使複材的抗彎強度有效提升至180 MPa，且鍍覆鋯基金屬玻璃薄膜的鎂基塊狀金屬玻璃複材抗彎強度更可提高到了254 MPa。由此推論，鋯基金屬玻璃薄膜能有效地覆蓋試片表面的缺陷以及抑制試片表面第一個裂縫的產生，進而提升抗彎強度。另外透過電化學腐蝕試驗(動態極化曲線)得到鍍覆鋯基金屬玻璃薄膜之鎂基塊狀金屬玻璃複材的腐蝕電流密度為9.16x10-8 A/mm2，而鎂基塊狀金屬玻璃基材與複材分別為8.69x10-7 A/mm2與5.65x10-6 A/mm2。因此，由電化學腐蝕試驗的結果可看出鋯基金屬玻璃薄膜可以提供保護鎂基塊狀金屬玻璃複材更優越的耐腐蝕性。;In order to improve the mechanical properties as well as corrosion resistance of Mg-based metallic glass (BMG) and Mg-based metallic glass composite (BMGC). The Zr-based metallic glass thin film (MGTF) of 200 nm thickness was coated on the Mg-based BMGC with two different buffer layers, Al-Ti (25 nm/25 nm) and Cu(50 nm), for adhesion ability investigation. The BMGC plates (with dimension of 4 mm W x 3 mm T x 35 mm L) of Mg58Cu31Gd11 with 25 vol.% Mo particles (size of 25 m) [2] was selected as the substrate and coated with 200 nm Zr-based ((Zr53Cu30Ni9Al8)99.5Si0.5) MGTF by DC-sputtering. The results of 3-point bending test show that the flexural strength of the Mg-based BMGC (180 MPa) can be significantly enhanced to 254 MPa for the Mg-based BMGC with 200 nm Zr-based MGTF coating. The remarkable increase in flexural strength of the Mg-based BMGC coated with Zr-based MGTF is suggested that the Zr-based MGTF can smooth the surface (by covering the defects on the specimen surface) to prevent the stress concentration and also provide residual stress to suppress the crack initiation from the specimen surface during bending test. In addition, the results of polarization electrochemical test reveal that the Zr-based MGTF exhibits much better corrosion resistance in 0.9 wt. % sodium chloride solution. Accordingly, the coating of 200 nm Zr-based MGTF on the Mg-based BMGC by sputtering is believed a promising method to protect the Mg-based BMGC from the island environment.
