Hot corrosion behavior of three different zones of linear friction welded Ti-22Al-25Nb alloy

Xi Chen, Faqin Xie, Tiejun Ma, Wenya Li, Xiangqing Wu

Research output: Contribution to journalArticlepeer-review

8 Scopus citations

Abstract

Ti-22Al-25Nb joint was achieved by using linear friction welding (LFW) technique. The hot corrosion behavior of base metal, weld zone, and thermo-mechanically affected zone (TMAZ) was investigated at 700 °C in 25% NaCl-75% Na 2 SO 4 (wt%) mixed molten salt. In the initial stage, the base metal and joint exhibit similar oxidation resistant ability, and the corrosion products formed on all zones are mainly composed of TiO 2 , Nb 2 O 5 , and Al 2 O 3 . The formation of NaNbO 3 first occurs in base metal and TMAZ after 50 h, while the weld zone is free of NaNbO 3 until 100 h. The development of pitting corrosion in both base metal and TMAZ is caused by the diffusion of sulfur and re-oxidation of sulfides. After a prolong exposure in molten salts, more serious sulfuration, acid dissolution, and escape of gaseous chlorides occurred in base metal leading to a drastic acceleration of corrosion rate.

Original languageEnglish
Pages (from-to)612-622
Number of pages11
JournalMaterials and Corrosion
Volume70
Issue number4
DOIs
StatePublished - Apr 2019

Keywords

  • hot corrosion behavior
  • linear friction welding
  • pitting corrosion
  • sulfuration
  • Ti-22Al-25Nb alloy

Fingerprint

Dive into the research topics of 'Hot corrosion behavior of three different zones of linear friction welded Ti-22Al-25Nb alloy'. Together they form a unique fingerprint.

Cite this