New insights into serrated flow in Pt2Mo-type superlattice strengthened Ni-Cr-Mo alloy at room temperature

It is found that the Portevin-Le Chatelier (PLC) effect can occur in a Ni-Cr-Mo alloy containing ordered phase with Pt2Mo-type structure during uniaxial tensile tests at room temperature with strain rate of 10(-3) s(-1). The serrations exhibit an embedded characteristic, i.e. a small serration is embedded in two adjacent large serrations. Both formation of order-disorder transformation-induced twins and twinning of ordered phase itself are responsible for the occurrence of the serrations, which generally arise from dynamic strain aging (DSA) that is widely accepted as the underlying mechanism for the PLC effect. (C) 2015 Elsevier B.V. All rights reserved.