Wahlmann B, Körner C, Nunn M (2021)
Publication Language: English
Publication Type: Journal article
Publication year: 2021
Claddings made of nickel-base alloys or stainless steel are frequently used in the oil, chemical, and power generation industries to protect low-alloy steels from corrosion. Arc weld overlays, which are commonly deposited, often exhibit microstructures near the fusion line that are susceptible to cracking. Due to its very localized and controlled heat input, electron beam welding has the potential to produce claddings with a more resistant microstructure. In this study, multi-layer nickel-base alloy and stainless steel claddings were fabricated by wire-feed electron beam additive manufacturing. Dilution was high because of the specific wire melting technique. It was found that the degree of dilution had a considerable influence on the precipitation of secondary phases, which, however, did not impair the integrity of the claddings. The influence of dilution on the formation of precipitates could be rationalized with thermodynamic calculations. In the nickel-base alloy claddings, the fusion line was sharp without any interfacial martensite. Only a few potentially detrimental type-II grain boundaries were found. Instead, epitaxial solidification was prevalent. This was attributed to metastable melting that was caused by high heating rates. Thus, electron beam-based manufacturing could produce claddings that are more resistant to disbonding than standard arc weld overlays.
Wahlmann, B., Körner, C., & Nunn, M. (2021). Electron Beam Wire Cladding of Nickel Alloys and Stainless Steel on a Reactor Pressure Vessel Steel. Materials Science and Engineering A-Structural Materials Properties Microstructure and Processing. https://dx.doi.org/10.1016/j.msea.2021.141082
Wahlmann, Benjamin, Carolin Körner, and Mike Nunn. "Electron Beam Wire Cladding of Nickel Alloys and Stainless Steel on a Reactor Pressure Vessel Steel." Materials Science and Engineering A-Structural Materials Properties Microstructure and Processing (2021).