Effect of Hf substitution Cu on glass-forming ability, mechanical properties and corrosion resistance of Ni-free Zr–Ti–Cu–Al bulk metallic glasses

• Published in: Journal of alloys and compounds 2019-10, Vol.806, p.668-675
• Main Authors: Jin, Z.S., Yang, Y.J., Zhang, Z.P., Ma, X.Z., Lv, J.W., Wang, F.L., Ma, M.Z., Zhang, X.Y., Liu, R.P.
• Format: Article
• Language: English
• Subjects: Aluminum; Amorphous alloys; Amorphous materials; Compressive strength; Copper; Corrosion behavior; Corrosion currents; Corrosion effects; Corrosion resistance; Glass formation; Glass-forming ability; Mechanical properties; Metallic glasses; Nickel; Plastic deformation; Substitutes; Substitution of Hf with Cu; Suction; Sulfuric acid; Titanium; Zirconium; Zr-based bulk metallic glasses
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2019.07.240

A series of Ni-free Zr55Ti3HfxCu32-xAl10 (x = 0, 1, 2, 3, 4, 5 at. %) bulk metallic glasses (BMGs) were developed by copper mold suction-casting. The effect of partially substituting Cu by Hf was investigated in terms of glass-forming ability (GFA), mechanical properties, and corrosion behavior. As a result of the partial substitution, the GFA of Hf-bearing amorphous alloys were significantly enhanced as compared to Zr55Ti3Cu32Al10 BMGs. Hf addition also enlarged the supercooled liquid region from 55 K to 70 K. The critical diameter was found to increase from 4 mm to 8 mm for x = 3. The corresponding compressive yield strength was over 1800 ± 21 MPa with a large plastic strain above 2.60 ± 0.10%. Electrochemical tests indicated that the lowest corrosion current density was 1.6 ± 0.1 × 10−8 A/cm2 for the alloy with x = 5 in H2SO4 solution, thereby yielding a superior corrosion resistance. •Partial substitution of Hf with Cu greatly enhanced the GFA of BMGs.•The Hf-bearing BMGs show a higher σy of 1800 ± 21 MPa and a large εp of 2.60 ± 0.10%.•The lowest icorr of BMGs is 1.6 ± 0.1 × 10−8 A/cm2 in H2SO4 solution.