Korrosion thermisch gespritzter Schichten auf der Basis von Aluminiumoxid

✍ Scribed by C.C. Stahr; L.-M. Berger; F.-L. Toma; M. Herrmann; D. Deska; G. Michael

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 350 KB
• Volume: 39
• Category: Article
• ISSN: 0933-5137
• DOI: 10.1002/mawe.200800387

✦ Synopsis

In this paper, the results of corrosion investigations performed on thermally sprayed coatings with different compositions in the Al 2 O 3 -TiO 2 system (Al 2 O 3 , Al 2 O 3 -3 %TiO 2 , Al 2 O 3 -40 %TiO 2 , Al 2- TiO 5 ) are presented. The coatings were deposited on corrosion-resistant stainless steel substrates using APS and HVOF processes. The coatings were characterized by means of optical microscopy and SEM of metallographically prepared cross sections as well as surfaces before and after corrosion testing. The changes in phase composition occurring during spraying were studied by X-ray diffraction. The corrosion experiments were performed with 1 N solutions of NaOH and H 2 SO 4 at room temperature, 60 C, and 85 C. In contrast to expectations, APS-sprayed coatings were found to be more corrosion-resistant than the denser HVOF-sprayed coatings were.

Key words: atmospheric plasma spraying (APS), high velocity oxy-fuel spraying (HVOF), Al 2 O 3 /TiO 2 system, microstructure, corrosion properties