Surface vitrification of alloys by pulsed electrical discharge treatment

Pulsed electrical discharge (PED) treatment was applied as a novel method to synthesize amorphous or amorphous/crystalline composite layers on the surfaces of Zr-, Fe-, Ti- and Al-based crystalline alloys. The formation of amorphous or amorphous/crystalline composite layers was investigated in terms of the significant disparity in glass-forming ability of the alloys. The influences of PED processing parameters on the surface glass formation of Zr55Al10Ni5Cu30 alloy were further discussed and the PED-treated alloy exhibited a gradient structure: amorphous surface, amorphous/crystalline composite region and crystalline substrate from surface to inside. Besides, effects of processing parameters on the microhardness and corrosion behavior of the treated Zr55Al10Ni5Cu30 alloy were investigated and the results revealed that the PED treatment could improve the microhardness and corrosion resistance of the crystalline substrate alloy. This PED treatment is a promising method to synthesize amorphous or amorphous/crystalline composite layers for novel mechanical, physical or chemical applications. •PED treatment was applied as a novel method to synthesize amorphous layers.•PED-treated alloy exhibits a gradient structure from surface to inside.•Improved surface microhardness and stability after PED treatment.