Hot-Corrosion and Particle Erosion Resistance of Co-Based Brazed Alloy Coatings

Crystals

Albert Titus Constantin¹  Gabriela Mărginean²  Ion-Dragoș Uțu³  Iosif Hulka⁴  Norbert Kazamer⁵ 

[1] Department of Hydrotechnical Engineering, Civil Engineering Faculty, Politehnica University of Timișoara, Splaiul Spiru Haret 1A, 300222 Timișoara, Romania;Department of Materials Science and Testing, Westphalian University of Applied Sciences Gelsenkirchen Bocholt Recklinghausen, Neidenburger Str. 43, 45897 Gelsenkirchen, Germany;Department of Materials and Manufacturing Engineering, Faculty of Mechanical Engineering, Politehnica University of Timișoara, Blvd. Mihai Viteazu, 300222 Timișoara, Romania;Research Institute for Renewable Energies, Politehnica University of Timișoara, G. Muzicescu 138, 300501 Timișoara, Romania;Westphalian Energy Institute, Westphalian University of Applied Sciences Gelsenkirchen Bocholt Recklinghausen, Neidenburger Str. 43, 45897 Gelsenkirchen, Germany;

关键词: co-based alloys;    hot corrosion;    solid particle erosion;    microstructure;    brazing;   

DOI  :  10.3390/cryst12060762

来源: DOAJ

【 摘 要 】

Tape brazing constitutes a cost-effective alternative surface protection technology for complex-shaped surfaces. The study explores the characteristics of high-temperature brazed coatings using a cobalt-based powder deposited on a stainless-steel substrate in order to protect parts subjected to hot temperatures in a wear-exposed environment. Microstructural imaging corroborated with x-ray diffraction analysis showed a complex phased structure consisting of intermetallic Cr-Ni, C-Co-W Laves type, and chromium carbide phases. The surface properties of the coatings, targeting hot corrosion behavior, erosion, wear resistance, and microhardness, were evaluated. The high-temperature corrosion test was performed for 100 h at 750 °C in a salt mixture consisting of 25 wt.% NaCl + 75 wt.% Na₂SO₄. The degree of corrosion attack was closely connected with the exposure temperature, and the degradation of the material corresponding to the mechanisms of low-temperature hot corrosion. The erosion tests were carried out using alumina particles at a 90° impingement angle. The results, correlated with the microhardness measurements, have shown that Co-based coatings exhibited approximately 40% lower material loss compared to that of the steel substrate.

【 授权许可】

Unknown