skip to main content

Title: Discontinuities in welds--cause and effect

The prime reason for the rejection or failure of weldments is the presence of defects or discontinuities produced during welding. The generation or introduction of the discontinuities in a welded structure can result when the delicate balance of welding variables is upset. Of more importance is the determination of the effect of weld discontinuities. Will the discontinuity influence the weldment in its intended service and thus be termed a defect. Or can we ''live with'' a particular discontinuity, since it does not influence the future service of the weldment. These questions are asked over and over again and the answers, although sometimes difficult to obtain, are becoming available. Unfortunately, the terminology concerning weld discontinuities and/or weld defects grew without rigorous definition. Terms such as crack, fissure, porosity, shrinkage, void, flaw, defect, discontinuity, defective weld, acceptable weld, and others had not been officially defined by the AWS until recently. It is with some wonder we have progressed this far without hard definitions. Many have called attention to the connotation of the word defect that is normally applied to discontinuities of the type encountered in welds. They proposed the use of the term discontinuity in order to avoid the natural conclusion bymore » the uninitiated to consider a weld defective if it contains ''defects,'' a prejudice certainly not intended even by the least knowledgeable individuals in the welding field. Over the last several years a series of definitions applies the word discontinuity to all interruptions of the typical structure of a weldment until the nature or accumulated effect of the discontinuities renders the part or product unable to meet acceptance standards or specifications. Then, the term defect applied. The cascading series of definitions is published in AWS A 3.0--''Terms and Definitions.''« less
Authors:
Publication Date:
OSTI Identifier:
7057938
Resource Type:
Journal Article
Resource Relation:
Journal Name: J. Mater. Energy Syst.; (United States); Journal Volume: 5:3
Research Org:
Dept. of Chemical Metallurgical and Polymer Eng., Univ. of Tennessee
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; DEFECTS; STANDARDIZED TERMINOLOGY; WELDED JOINTS; FAILURE MODE ANALYSIS; SPECIFICATIONS; STANDARDIZATION; WELDING; FABRICATION; JOINING; JOINTS; SYSTEM FAILURE ANALYSIS; SYSTEMS ANALYSIS 360101* -- Metals & Alloys-- Preparation & Fabrication; 360401 -- Polymers & Plastics-- Preparation & Fabrication-- (-1987)