Report

Making ultrastrong steel tough by grain-boundary delamination

See allHide authors and affiliations

Science  07 May 2020:
eaba9413
DOI: 10.1126/science.aba9413

You are currently viewing the abstract.

View Full Text

Log in to view the full text

Log in through your institution

Log in through your institution

Abstract

Developing ultrahigh strength steels that are ductile, fracture resistant, and cost-effective would be attractive for a variety of structural applications. We show that improved fracture resistance in a steel with an ultrahigh yield strength of nearly 2GPa can be achieved by activating delamination toughening coupled with transformation induced plasticity. Delamination toughening associated with intensive but controlled cracking at Mn-enriched prior-austenite grain boundaries normal to the primary fracture surface dramatically improves the overall fracture resistance. As a result, fracture under plane-strain conditions is automatically transformed into a series of fracture processes in “parallel” plane-stress conditions through the thickness. The present “high-strength induced multi-delamination” strategy offers a different pathway to develop engineering materials with ultra-high strength and superior toughness at economical materials cost.

View Full Text

Stay Connected to Science