Details

Autor(en) / Beteiligte

• Chen, Tingting
• Shi, Yongjun
• Liu, Zhitong
• Guo, Yankuo
• Wang, Shuyao
• Zhang, Wenping
• Yao, Zhongfu

Titel

Role of nitrogen and tantalum in the high-temperature oxidation behavior of AlCoCr0.5NiTaxTi(N) alloys synthesized by laser in situ synthesis

Ist Teil von

• Surface & coatings technology, 2024-06, Vol.486, p.130953, Article 130953

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2024

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Laser cladding was used to synthesize the coatings of the AlCoCr0.5NiTaxTi (N) alloys on a Ti–6Al–4 V substrate. As the Ta content increased, the alloy evolved from columnar crystals composed of dendritic face-centered cubic (FCC)/L12 phases and interdendritic Laves phases to a eutectic structure. The high-valence state of Ta diminished oxygen vacancies in TiO2, which reduced the diffusion rate, so an appropriate Ta content improved high-temperature oxidation resistance. In the cladding process, nitrogen from the protective gas was partially dissolved in the alloy and partially formed Ti2N, both of which act as diffusion barriers for titanium, inhibiting the formation of titanium oxide and promoting the formation of continuous single aluminum oxide, thereby improving oxidation resistance at high temperatures. •AlCoCr0.5NiTaxTi(N) coating consists of FCC/L12 and Laves phases.•An increase in Ta content promoted the formation of eutectic structures.•These coatings, oxidized in air at 800 °C for 240 h, followed a parabolic law.•Ta reduced the oxygen vacancies in TiO2, thereby improving oxidation performance.•Ti2N and a nitrogen-rich solid solution within the coating inhibited TiO2 formation.