Weldability of Niobium Microalloyed Steels for Structural Application

Publication Author : Thiago De Souza Amaral; Leonardo Magalhães Silvestre
Publication Year : 2018
Publication Event :
Publication Theme : SQJ Vol 47 No.3
Publication Company :

SYNOPSIS:

SYNOPSIS

Niobium microalloyed steels have been shown to be an excellent solution for structure fabrication. Employing concepts developed for the oil and gas industry, the niobium microalloyed steels deliver high strength and high toughness with considerably low carbon content. However, the definition of the real welding needs and the benefits of applying this family of steels is not well described in the welding specifications most commonly used in the construction sector.

This paper demonstrates an example of real weld application in a HSLA steel class 65 ksi and a HSLA steel class 50 ksi. It was possible to determine using thermal simulations the recommended energy range of the weld more accurately, including the need or not of preheating, and show that they were comparable with real welds. The use of niobium HSLA steel shows benefits that include cost savings resulting from the elimination of preheating, reduction in material use and increase in the process speed.

Keywords: HSLA Steel, Niobium, Welding, Cost Effective, Standards.