NEW AMORPHOUS Al-La-Y-Ni(Fe)QUATERNARY ALLOYS WITH SUPERIOR STRENGTH AND DUCTILITY

The melt spun ribbons of Al-La-Y-Ni(Fe)quaternary alloys were prepared by a single-roller melt spinning technique in vacuum.Their amorphous nature,mechanical propertiesand tensile fracture surface morphology were investigated.The experimental results showthat amorphous alloys with high strength and good ductility as well as good thermalstability can be achieved in Al-La-Y-Ni(Fe)system,when the alloy contains 85—90at.-% Al and less than 10 at.-% La+Y.The maximum tensile fracture strength(σ_f)and microhardness(HV)are as high as 760 MPa and 294 DPN,respectively.The as-quenched ribbons can be bent 180 degree without fracturing.The dominant factors forformation of amorphous Al-La-Y-Ni(Fe)are the strong attractive interaction among Al,La,Y and a decrease of melting temperature.