Accession Number : ADA304347

Title :   Optimum Weld-Metal Strength for High-Strength Steel Structures.

Descriptive Note : Final rept.,

Corporate Author : LEHIGH UNIV BETHLEHEM PA CENTER FOR ADVANCED TECHNOLOGY FOR LARGE STRUCTURAL SYSTEMS

Personal Author(s) : Dexter, Robert J. ; Ferrell, Matthew

PDF Url : ADA304347

Report Date : 18 DEC 1995

Pagination or Media Count : 131

Abstract : This report provides data and analysis to support the acceptance of undermatched welds in high-strength steel in shipbuilding. Wide-plate tensile tests made from HSLA-l00 steel plate (690 MPa minimum yield strength) with transverse groove welds demonstrated that moderately-undermatched joints (actual weld yield strength up to 12 percent less than actual base-plate yield strength) can achieve strength and ductility as high as overmatched welds. Welds undermatched between 18 and 28 percent exhibited full strength but minimal ductility. Relatively coarse-mesh elastoplastic finite-element analysis adequately reproduced the behavior observed in the experiments. Wide-plate specimens were prepared with various controlled intentional defects in both moderately-undermatched and overmatched welds. These defect specimens exhibited remarkable performance and there was no consistent difference between the results of the moderately-undermatched welds and the overmatched welds. When loaded in shear, groove welds undermatched up to 28 percent developed the required minimum shear strength of the MSLA-100 plate and had excellent ductility. Guidelines and commentary for design, finite-element analysis, selection of weld filler metal and welding procedure for various types of joints are given to facilitate the use of high-strength steel with optimum weld metal properties. (MM)

Descriptors :   *WELD METAL, *HIGH STRENGTH, *SHIPBUILDING, TENSILE STRENGTH, OPTIMIZATION, FINITE ELEMENT ANALYSIS, CRACKING(FRACTURING), DISPLACEMENT, STRAIN(MECHANICS), COOLING, STRENGTH(MECHANICS), STEEL, WELDS, DEFECTS(MATERIALS), SHEAR STRESSES, STRAIN GAGES, FATIGUE(MECHANICS), DUCTILITY, YIELD STRENGTH, TOLERANCES(MECHANICS), GROOVING, WELDABILITY, WELDING, JOINTS, SHEAR STRENGTH, FILLERS.

Subject Categories : Properties of Metals and Alloys
      Marine Engineering

Distribution Statement : APPROVED FOR PUBLIC RELEASE