Properties And Board Continuous Casting Of Cu-Zr-Al Glassy Alloys

Glassy alloy has special range order atomic structure, which lead to many good properties, such as high strength, high hardness,high corrosion resistance,good wear resistance,good magnetic properties and biocom patibility. However, it has not been widely used in industry, because the preparation methods and critical dimension limited its developmentThis thesis has been done to solve the problem of glassy alloys’ application and improve the quality of people’s lives. XRD, SEM,DSC and DTA have been used to study the properties（theriml stability, hardness,corrosi on resistance,wear resi stance,biocompatibility）of ternary Cu-Zr-Al glassy alloys prepared in copper mold. Vacuum multi-mold continuous casting system has been designed and established for the metallic glasses continuous casting.The super cooled liquid region of Cu₄₀Zr₅₀Al₁₀, Cu₄₀Zr₄₅Al₈ and Cu₅₀Zr₄₂Al₈ were wide（>70 K）,which indicated their good thermal stability. The ternaty Cu-Zr-Al glassy alloys have high hardness（>570HV）. With increasing the content of Cu, there exhibits an increase in the hardness of the alloys. The glassy alloys exhibits excellent corrosion resistance in 3.5%NaCl solution and 0.5 mol/L H₂SO₄ solution, and Cu₅oZr₄₂Al₈ glassy alloy was the best of them With increasing the content of Cu, an increase appeared in corrosion resistance of the alloys. The ternaty Cu-Zr-Al glassy alloys showed a better wear resistance than Ti6A14 V and Cu_5oZr₄₂Al₈ glassy alloy was the best of the four albys. The wear resistance has been improved by increasing the content of Cu,which was same as what happened in the hardness tests. Cu₄₀Zr₅₀Al₁₀ glassy alloy has better biocompatib ility than other twoglassy alloys. Zr has been certified to beto improve biocompatib ility.Vacuum multi-mold continuous casting system has been designed and established to study the methods of metallic glass board continuous casting. It has been foud that highdrawing speed,high melting temperature, low pressure were bad for the quality of pure aluminum board. Moreover, continuous casting was helpful to get purer conponents. At last,a 50mmX 6mmX 300mm Cu₄₀Zr₅₀Al₁₀ board with good high quality has been prepared.