Experimental Study on Welding of Q550qENH High Performance Weather Resistant Bridge Steel

Compared with conventional bridge steel， weather-resistant bridge steel takes both mechanical properties and weather resistance into account， and has a promising application prospect in steel bridge engineering. However， the addition of alloy elements has a certain impact on the welding performance. For Q550qENH weather-resistant bridge steel plates， a series of experimental study was conducted， including material reinspection test， welding material reinspection test， steel plate welding performance test， a series of temperature impact test for butt joints， and welding process qualification test for typical joints. The matching welding materials for Q550qENH weather-resistant bridge steel plates were determined. The welding performance and weather resistance of this steel grade were evaluated and analyzed. And welding process qualification tests were carried out according to relevant standards. The test results showed that the -40 ℃ low-temperature impact energy A_kV2 of the weld metal was above 54 J， and the value of the corrosion resistance index I was above 6.5， which met the requirements of the relevant steel bridge manufacturing specifications. This provided technical support for the promotion and application of weather-resistant bridge steel in large-scale bridges.