摘要
In this paper,high-zirconium Zr66+2xAl9-x(Ni1/3Cu2/3) 25-x(x=0,1,2 at.%) bulk metallic glasses with high strength and large ductility were fabricated by copper mould casting.The effects of zirconium content on the glass-forming ability(GFA),thermal properties and mechanical properties were investigated using X-ray diffractometer(XRD),differential scanning calorimeter(DSC),and mechanical testing system in compressive and three-point bending modes,respectively.The high-zirconium BMGs show the critical diameters of 3-5 mm,the supercooled liquid region ranging from 70 K to 99 K,and the yield strength of over 1700 MPa.The Zr 70 Al 7(Ni1/3Cu2/3) 23 BMG exhibits a large compressive plastic strain up to 21% and a high notch toughness value of 60.6 MPa m 1/2.The increase in Zr content results in the decrease in GFA and thermostability,and in the improvement of plasticity under compressive and three-point bending conditions.The superior plasticity of high-zirconium BMGs is attributed to their high Poisson's ratio and small elastic modulus ratio /B.
In this paper, high-zirconium Zr66＋2xAl9-x（Ni1/3Cu2/3）25-x （x=0,1,2 at.%） bulk metallic glasses with high strength and large duc- tility were fabricated by copper mould casting. The effects of zirconium content on the glass-forming ability （GFA）, thermal properties and mechanical properties were investigated using X-ray diffractometer （XRD）, differential scanning calorimeter （DSC）, and mechanical testing system in compressive and three-point bending modes, respectively. The high-zirconium BMGs show the critical diameters of 3-5 ram, the supercooled liquid region ranging from 70 K to 99 K, and the yield strength of over 1700 MPa. The Zr70Al7（Ni1/3Cu2/3）23 BMG exhibits a large compressive plastic strain up to 21% and a high notch toughness value of 60.6 MPa m1/2. The increase in Zr content results in the decrease in GFA and thermostability, and in the improvement of plasticity under compressive and three-point bending conditions. The superior plasticity of high-zirconium BMGs is at- tributed to their high Poisson＇s ratio and small elastic modulus ratioμl/B.
