INVESTIGATIONS OF BRITTLE CLEAVAGE FRACTURE OF WELDED FLAT PLATE BY MEANS OF A BEND TEST
Reported herein are the results of several series of bend tests conducted on 10-in. square by 3/4-in. thick plates upon which had been deposited weld metal. The experiments were carried out in conjunction with tests on large welded tubes of ship plate. This report presents a description of the test specimens and the testing technique. Both double-V butt-welded and single-bead specimens were tested as simple beams supported on a 6-in. span, centrally loaded. The weld or bead was so placed that it was stressed in tension by the applied load. Tests were made at various temperatures ranging from room temperature to -40 deg F on specimens welded with E6010 electrodes, low-alloy steel electrodes, 25-20 stainless steel electrodes, and with Unionmelt. The effects on ductility at -40 deg F of preheating to various temperatures ranging from 0 deg F to 500 deg F, of postheating to 1100 deg F, and of normalizing were determined. The effect of arc voltage and the effect of the weld contour on the ductility at various temperatures were determined for E6010 and Unionmelt deposits. Chemical analyses of typical weld deposits were made and the microstructure of most of the specimens was studied, and microhardness surveys were conducted on about half of the specimens tested. Included in the report are the following data: welding conditions, testing temperature, bend angle, maximum elongation, maximum load and type of failure, microstructures, and hardness values. The cracks were found to originate in the weld metal and not in the heat-affected zone of the base plate even though the heat-affected zone was in many cases much harder than the weld metal. The ductility of the bend test specimens was found to be improved by preheating, postheating, low arc-voltage and by the use of stainless steel electrodes. The ductility was decreased by low preheat temperature, low testing temperature, fast rate of electrode travel, high arc voltage, and by the use of electrodes having high hardenability.
University of California, BerkeleyCollege of Engineering
Berkeley, CA USA 94720
Ship Structure CommitteeNational Academy of Science, 2101 Constitution Avenue, NW
Washington, DC USA 20418
- DAVIS, H E
- TROXELL, G E
- Parker, E R
- Boodberg, A
- Publication Date: 1948-3-10
- Pagination: 111 p.
- TRT Terms: Bend tests; Butt welds; Cleavage fracture; Fracture mechanics; Plate bearing test; Weld tests
- Identifier Terms: Ship Structure Committee
- Old TRIS Terms: Ship plates
- Subject Areas: Marine Transportation; Materials;
- Accession Number: 00330976
- Record Type: Publication
- Source Agency: Ship Structure Committee
- Report/Paper Numbers: SSC- 6 Tech Rpt.
- Contract Numbers: NObs-31222, NObs-34231
- Files: TRIS
- Created Date: May 21 1981 12:00AM