Improving the oxidation resistance of Cr-Si-based alloys by ternary alloying. (1st April 2020)

• Record Type: Journal Article
• Authors: Ulrich, Anke S.; Pfizenmaier, Petra; Solimani, Ali; Glatzel, Uwe; Galetz, Mathias C.
• Is Part Of: Corrosion science. Volume 165(2020)
• Publication Date: 2020-04-01
• Subjects: A. Alloy -- B. EPMA -- C. High temperature corrosion -- C. Selective oxidation; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2019.108376
• Languages: English
• ISSNs: 0010-938X

Abstract

Highlights: Alloying Cr with Si, Ge, Mo, and Pt improves oxidation and nitridation resistance. Cr-Si-Mo: N-resistant Mo-enriched Crss forms in the subsurface zone. Cr-Si-Ge: Ge decreases perturbations in oxidation kinetics. Cr-Si-Pt: Cr3 PtN forms instead of Cr2 N. Ge, Mo, or Pt alloying varies Cr2 O3 morphology. Abstract: Oxidation and nitridation behaviour of Cr, Cr91 Si9 [at.%], and different ternary Cr91 Si7 X2 (X = Ge, Mo, Pt) alloys were systematically investigated. Thermogravimetric analysis was conducted at 1200 °C for 100 h in synthetic air. Alloying was found to highly affect the oxidation and nitridation resistance. EPMA, XRD, SEM, and EBSD methods were employed to reveal the impact of different alloying elements on the formation of Cr2 N, on the subsurface zone, and on the structure of the oxide scale, consisting of Cr2 O3 and SiO2 . The formation of Cr2 N is highly reduced by alloying, which goes along with a change in oxide morphology.