Possibilities and Limitations to Improve the Weldability of Low Carbon 12Cr Ferritic Stainless Steel for Expanded Industrial Applications

Abstract

Ferritic stainless steel X2CrNi12 (EN 10088) is generally appreciated for its relatively low cost and good resistance to wet abrasion and mild environments, but unfortunately its weldability is restricted. Typical applications up to now include railway wagons for coal and iron ore, mining and mineral process and transport equipment, bus frames and chassis, silos, etc. This steel grade nowadays can be fabricated cost effectively with low carbon and impurity levels appreciably improving both the weldability and mechanical properties. In this case, long-term maintenance costs of assemblies produced using this ‘clean’ X2CrNi12 stainless steel will be low, with a suitable coating providing sufficient protection for several decades. For other applications, the use of weldable X2CrNi12 is also more economical than higher alloyed stainless steels. Moreover, joining the steel by laser welding without filler metal should be considered. The present paper provides an overview of results of a research project initiated by the Belgian Welding Institute investigating the possibilities of this modified low carbon ferritic stainless steel. The main objective of this work was to demonstrate that it offers great application ranges for constructing purposes which should expand its application field substantially. In the near future broadening this steel family with even higher mechanical properties allowing further reduction of plate or wall thickness and of production costs will be explored.