The influence of thermomechanical processing on recrystallisation and precipitation in austenitic alloys with particular reference to the effects of deformation and ageing conditions

摘要: Abstract The recrystallisation and precipitation behaviour of an austenitic stainless steel has been studied with particular emphasis on the role experimental parameters in controlling mechanisms sigma phase. alloy, containing 23 wt% chromium nickel negligible carbon (0.004 wt%), was aged isothermally at different temperatures following hot-, warm-, or cold-working. Three distinct behaviours during ageing were found: static 900°C; conventional phase after 800°C; ‘discontinuous recrystallisation’ (conjoint precipitation) 700°C 600°C. conditions thermomechanical processing interacted strongly history, hot-working having least influence cold-working greatest significance, a consequence combination amount strain energy available for degree supersaturation Recrystallisation adequate caused discontinuous recrystallisation, yielding very rapid heavy precipitation, apparently approaching thermodynamic equilibrium only few hours ageing. By contrast, gave light by same time. distribution, shapes, sizes precipitates influenced mechanism.