The objective of this research was to understand the melting and wetting behaviour of braze alloys and mechanical properties of brazed joints for pure zirconium plates and the Zr-based bulk metallic glass (BMG), Vitreloy 105 (Zr(_5)(_2)(_.)(_5)Cu(_1)(_7).(_9)Ni(_1)(_4)(_.)(_6)Al(_1)(_0)Ti(_5)). Active brazing alloy, Cusil ABA (Ag(_6)(_3)Cu(_3)(_5)(_.)(_2)(_3)Ti(_1)(_.)(_7)(_5)), has been used to braze Zr plates in the Gleeble 3500 thermo- mechanical simulator under vacuum at 3 temperatures (840, 940 and 1000 (^o)C) and with Vitreloy105 at 780 (^o)C. The shear strength of the brazed Zr-plate increased at lower brazing temperatures; brazing of Vitreloy 105 plates was not successful as the brazing temperature, (Cusil ABA liquidus temperature) exceeded its crystallisation temperature Tx=440 (^o)C leading to crystallization and embrittlement during to brazing. As a result, three BMG compositions (Mg(_6)(_5)Cu(_1)(_5)Ag(_1)(_0)Tb(_1)(_0)(_,)Zn(_4)(_0)Mg(_1)(_1)Ca(_3)(_1)Yb(_1)(_8) and Ca(_6)(_5)Mg(_1)(_5)Zn(_2)(_0)) as potential brazes for Vitreloy 105 with liquidus temperatures below the crystallisation temperature and high values of fracture strength have been selected to predict (using Thermo- Calc) the equilibrium reaction between substrate and braze prior to manufacture in order to estimate likely wettability and joint strength.
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