Abstract

The high heat input during fusion welding leads to transformations of the microstructure in the area subjected to welding, mostly resulting in a heterogene crystalline structure and an overall deterioration of the mechanical properties. To reduce the detrimental effect, posttreatment processes which are typically separated from the actual welding process are state of the art. The present work shows the new methodology, WeldForming, which intends to eliminate subsequent treatment processes. The new in-line process combination harnesses the synergies of a welding and a rolling process to ultimately prevent the typical zone formation of the heat affected zone. Experimental investigations combined with a detailed numerical simulation of the coupled welding and forming process indicate the functional proof of the new methodology. The validation of the numerical model is carried out with the aid of temperature profiles, cross sections, and microstructure analysis as well as flow curves determined by upsetting tests on thermomechanical simulation systems.

Highlights

  • Energy input is integral to all welding processes, which can lead to extensive transformations and changes of the microstructure and properties of these materials

  • Two plates are joined in a butt weld configuration with a sheet-thickness-dependent seam geometry according to DIN EN 9692-1 and with a defined face and root reinforcement

  • The welding results using three different welding characteristic curves are examined with regard to weld seam geometry, seam defects, and spatter tendency

Read more

Summary

Introduction

Energy input is integral to all welding processes, which can lead to extensive transformations and changes of the microstructure and properties of these materials This applies in particular to steel in the area of the weld metal [1, 2]. The characteristics of heat input during the welding process will lead to temperature gradients and different cooling rates during the solidification of the weld pool This can cause an irregular distribution of alloying elements (e.g., segregation) and various microstructural features after solidification may evolve. Recommended for publication by Commission IX - Behaviour of Metals Subjected to Welding This can in turn lead to undesirable properties of the whole component, e.g., the joint has inferior strength relative to the unaffected base material [4]. Experiments conducted on highstrength low-alloy steels by Mohandas [5] reveal the effect of the microstructural changes in the HAZ on the overall mechanical properties of the component

Objectives
Methods
Findings
Discussion
Conclusion
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call