Laboratory Investigation on Seams between Rails and Hardened Fine-grained, as well as Hadfield Steel Plates with Manual Arc Welding

Abstract

In the last decade, hardened fine-grained plate components have been used in turnouts and crossings on Western European urban rail networks, as well as in Hungary, in place of traditional rail or Hadfield steel components. The first crossing was built in Hungary in 2016. These components have many advantages, such as the ease with which they can be machined in the factory; they are less prone to cracking than rails due to their block design (high load-bearing cross-section); however, their weldability to rails and lifetime repairability present numerous challenges for railway turnout manufacturers and operators. There have been numerous studies on joint and repair welding of rails and hardened fine- grained materials, but there is little or no information available on joint welding with manual arc welding of these two different materials. The current study aims to investigate the welds of coated electrode manual arc welding of rails (R260 and R400 HT) and hardened fine- grained plates (in this case, Hardox 500) under non-laboratory conditions while strictly adhering to technological specifications, in comparison to manual arc welding of rails and Hadfield steels. Laboratory tests included raw material chemical composition, macroscopic tests, micro-hardness measurements, tensile, shear, and bending tests.