Rapidly solidified Al-6.5 wt.% Ni alloy

Aluminium-nickel alloy with nominal composition 6.5 wt.% Ni has been manufactured by chill-casting and melt-spinning methods. The resulting microstructures have been examined by optical microscopy (OM) and scanning electron microscopy (SEM). These results showed that the microstructure of the rapidly solidified ribbons is clearly different from that of the chill-casting alloy. The effect of the wheel speed on rapidly solidified ribbons dimension and the relationship between ribbon thickness and wheel speed was also examined. It was found that there is good relationship between ribbon thickness and wheel speed. The ribbon thickness decreased inversely with the wheel speed. Furthermore, the microhardness of the chill-casting alloy and the rapidly solidified ribbons were measured by using a Vickers indenter. The result showed that the microhardness of the rapidly solidified ribbons is higher than that of chill-casting alloy. (C) 2003 Elsevier Science B.V. All rights reserved.