Diffusion bonding of Zr_(55)Cu_(30)Ni_5Al_(10) bulk metallic glass to Cu with Al as transition layer

摘要

In this work we demonstrate the diffusion bonding of Zr_(55)Cu_(30)Ni_5Al_(10) bulk metallic glass (BMG) to aluminum and copper alloy. The process parameters including temperature, pressure and time are investigated experimentally, and we obtain appropriate ones for accomplishing diffusion bonding of the BMG to aluminum alloy successfully. Then we present a two-step diffusion bonding process to bond the BMG to copper alloy by using aluminum alloy as transition layers, and achieve a five-layer bonded joint of BMG/Al/Cu/Al/BMG. The mechanical properties of the multilayer joint are examined. The hardness of the BMG in the joint is enhanced while the bending strength decreases significantly compared with the as-received BMG. Besides, the crystalline metals alleviate and block the extension of cracks in the BMG, which results in the joint fracturing in an explosion-proof glass manner, dissimilar to rupturing in a catastrophic manner that is always happened in the BMGs. Therefore, diffusion bonding of BMG to crystalline metals is a promising way to extend its application.