CLEAVAGE TOUGHNESS OF HETEROGENEOUS MATERIALS AND APPLICATION TO WELDED JOINTS

Abstract

Abstract—Toughness is generally considered as a property of homogeneous materials. In this paper, the main interest is devoted to the cleavage toughness of multi‐materials. Weldments are a special case of these heterogeneous materials and are of great importance because of their wide applications. The case of a crack front intercepting more than one material is investigated experimentally and numerically. The agreement is generally very good. The special case of a brittle core zone located all along the crack‐tip is investigated only with numerical tools. However, a special feature arising from this study is that a critical HAZ size can be defined. Below this critical size, the failure probability should never exceed a selected value (e.g. 10%). This could be used as a design rule for multipass weldments.