01697825

Component

ASTM A709 Grade 50CR is a bridge steel designed to address the issue of prolonged wetness combined with chlorine containing salts which hinders the formation of a passive layer on traditional weathering steels. Due to the limited amount of information on the welding parameters for 50CR, this study investigated the effects of using 4 different welding filler wires (ER309L, ER309LC, ER309LSi, and ER316L) in conjunction with a specific heat input (75 kJ/in) and maximum interpass temperature (450 °F) on half-inch groove welded plates, selected from a larger set. This study reports the absorbed fracture energies obtained with Charpy V-notch testing on full size samples performed at a range of temperatures, including those specified by ASTM and AWS standards for zone 2. The ductile to brittle transition temperature (DBTT) of 50CR was found to be -40 °F, a thirty degree improvement from conventional weathering steel, 50W. The only sample plate that failed to meet AWS D1.5 in this study was welded with 309L, a heat input of 75 kJ/in, and a maximum interpass temperature of 450 °F, with an average fracture energy of 17 ft-lbs. The sample plate welded with 309LC showed a high amount of ductility across all Charpy test temperatures, and an average fracture energy of 41 ft-lbs at the AWS D1.5 testing temperature. Microstructure and fracture analysis were performed using conventional optical and scanning electron microscopy.

This paper was sponsored by TRB committee AFH70 Standing Committee on Fabrication and Inspection of Metal Structures.

19-02733

English

5p

2019

Transportation Research Board 98th Annual Meeting

Digital/other

Figures; References; Tables

Steel bridges; Steel plates; Structural steel; Submerged arc welding; Temperature

Bridges and other structures; Energy; Materials

Transportation Research Board Annual Meeting 2019 Paper #19-02733

TRIS, TRB, ATRI

Dec 7 2018 9:38AM