Improved properties and thermal stability of a titanium-stainless steel solid-state weld with a niobium interlayer. (20th July 2021)

• Record Type: Journal Article
• Authors: Li, Jianxiong; Vivek, Anupam; Daehn, Glenn
• Is Part Of: Journal of materials science & technology. Volume 79(2021)
• Page Start: 191
• Page End: 204
• Publication Date: 2021-07-20
• Subjects: Impact spot welding -- Titanium alloy -- Stainless steel -- Nb interlayer -- Thermal exposure -- Phase transformation; Metals -- Periodicals; Materials science -- Periodicals; Materials science; Metals; Periodicals; 620.1105
• DOI: 10.1016/j.jmst.2020.11.050
• Languages: English
• ISSNs: 1005-0302

Abstract

Graphical abstract: Highlights: High strength solid-state welds were demonstrated between Ti and stainless steel through an impact welding method. By incorporating a Nb interlayer these impact welds are stronger and more thermally stable. With modest thermal exposure, Ti/Nb/SS welds presented improved toughness. The effective operation temperature ranges are suggested for Ti-SS and Ti-Nb-SS spot impact welds. Abstract: Stainless steel (SS) and titanium alloys can be welded in the solid-state by high speed oblique impact. Here, the effect of a niobium (Nb) interlayer on weld strength and thermal stability is evaluated. Both Ti/SS and Ti/Nb/SS welds were subjected to thermal exposure ranging from 300 °C to 950 °C for 1.5 h. Thermal exposure monotonically decreases the strength and toughness of the Ti/SS pair with a dramatic falloff in strength and change in failure mode from partial pullout failure to full interfacial fracture at 600 °C. With the interlayer, toughness was increased versus baseline up to 700 °C thermal exposure and then intermetallic formation again caused falloff in properties. Guidelines for the production, properties and applications of these classes of welds are provided.