Effect of solutes on the dynamic recrystallization microstructure of nickel

Abstract. Solute drag effects during dynamic recrystallization were studied using four different nickel-sulphur alloys containing &om 1 to 20 wt. ppm of sulphur. It was shown in an earlier paper that the steady state stress for.dynamic recrystallization depends on the sulphur concentration. The aim of this paper is to discuss the effect of sulphur on the steady state grain size durin dynamic recrystallization. The compression tests were carried out between 650°C and 1200°C at a constant strain rate of 10 ' S- ' until a strain of 1 was attained. The samples were then quenched in water within Is. The grain sizes were measured after interrupted compression tests using both optical micrography and orientation imaging microscopy (OM) measurements. As expected, the grain sizes decrease when the solute concentration is increased. A model taking into account the reduction of the mobility of random grain boundaries due to their interaction with sulphur and the occurrence of twinning is proposed to account for the steady state grain size during dynamic recrystallization. 1