Tensile Flow Behavior of 9Cr–2WVTa Reduced Activation Ferritic/Martensitic Steel

Abstract

Tensile flow behavior of 9Cr–2WVTa ferritic/martensitic (RAFM) steel in normalizedtempered condition has been studied based on Voce equation over the temperature range of 25–600 آ°C. Yield strength (YS) and ultimate tensile strength (UTS) decrease with increase in temperature. However, the elongation decreases with increase in temperature up to 400 آ°C and then increases beyond 400 آ°C. True stress–true plastic strain curves at all temperatures are adequately described by the Voce equation. While saturation stress (دƒs) decreases with temperature, the rate at which the stress approaches the saturation value (nV) increases with temperature. The variation of the stress increment up to saturation stress (دƒun) with temperature shows a plateau in the temperature range of 200–400 آ°C. Moreover, the product of دƒun and nV (دƒunآ·nV) is inversely proportional to the elongation. The relation of elongation to دƒunآ·nV can be described by a power law with the exponent of −1.63.