A Ti36.27-Zr12.50-Cu37.48-Ni12.50-Hf1.25 (at.%) amorphous ribbon was developed via melt-spinning and employed as a vacuum brazing filler to join Ti-6Al-4V (TC4) to SS316L. The effects of brazing temperature (910-950 °C) and dwell time (5-40 min) on the microstructure and mechanical performance of joints were systematically examined. The optimal shear strength of 360 ± 12 MPa was achieved at 910 °C for 40 min, which was closely matched by the joint brazed at 910 °C for 10 min (353 ± 9 MPa). By contrast, higher temperatures induced the formation of coarse intermetallic layers, leading to a strength reduction of up to 50%. Microstructural analysis revealed three distinct zones: (α + β)-Ti diffusion layer with α-Ti lamellae, a central eutectic/intermetallic seam, and an Fe-Cr-rich interface. Growth kinetics followed parabolic time and Arrhenius temperature dependence, yielding activation energies of 261 kJ/mol (TC4 side) and 149.6 kJ/mol (SS316L side). Microhardness mapping identified the Ti₂Cu and TiFe phases as indispensable strengthening constituents; however, their inherent brittleness simultaneously rendered them the primary embrittling sources. Fractography showed intermetallic cleavage on the SS316L side and mixed ductile-brittle failure on the TC4 side. This work defines a narrow brazing window for high-strength TC4/SS316L joints and underscores the critical balance between diffusion-driven bonding and intermetallic control.
Bano et al. (Sun,) studied this question.