The Effect of Initial Grain Size on Formability of AZ31B Magnesium Alloy during I-ECAP

Abstract

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The Origin of Fracture in the I-ECAP of AZ31B Magnesium Alloy

“…The results obtained in this work and in our previous study [22] showed that the initial grain size has a strong influence on the minimum temperature of I-ECAP. However, the effect of strain rate cannot be ignored as well; therefore, it is proposed to use a Zener-Hollomon parameter [34] to define the processing window:…”

“…In order to reduce temperature below 473 K (200°C), the grain structure of~2 lm or smaller is required. [13,22,36] It was found here that the relation between Zener-Hollomon parameter, Z, and the initial grain size of AZ31 required to avoid fracture, d initial , follows the power law:…”

“…[20,21] The preliminary results from I-ECAP experiments investigating the effect of grain size on formability in I-ECAP have been already published in our previous paper. [22] The work presented here has been extended by microstructural characterization, investigation of route effects on formability, and literature review reflecting similarities between fracture behavior of AZ31B magnesium alloy subjected to I-ECAP and conventional ECAP. Relations between mechanical properties and microstructures of the samples successfully I-ECAPed in this work have been published in the other articles.…”

In situ analysis of the influence of twinning on the strain hardening rate and fracture mechanism in AZ31B magnesium alloy

“…1. The origin of the billet distortion after I-ECAP by route B C was already discussed as related to strain rate sensitivity of non-uniformly strained material [16,17]. The irregular shape of the I-ECAPed billet has influenced the sample appearance after upsetting.…”

Producing High‐Strength Metals by I‐ECAP

“…The punch is moving in a reciprocating manner while the billet is fed into deformation zone in consecutive steps. As the first trials with pure aluminum and pure copper were successful, the work is now being continued with magnesium alloys [18][19][20][21] and other materials. The goal of the current work is to show the I-ECAP capability of improving strength of different alloys, which would extend the field of their possible applications.…”