Browsing by Author "Stokes J."

Filter results by typing the first few letters
Now showing 1 - 1 of 1
  • No Thumbnail Available
    Scopus
    Effect on microstructure of TiO2 rate in Al2O3-TiO2 composite coating produced using plasma spray method
    (2012-01-01) Islak S.; Buytoz S.; Ersoz E.; Orhan N.; Stokes J.; Hashmi M.S.; Somunkiran I.; Tosun N.
    In this study, Al2O3-TiO2 composite coatings were thermally sprayed on the SAE 1040 steel using atmospheric plasma spray (APS) process of mixed different rates micron-sized TiO2 and micron-sized Al2O3 powders. The effects of TiO2 addition on the microstructure, phase compositions and microhardness of the coatings were investigated by using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffractometry (XRD) and microhardness tester. The results show that the Al2O3-TiO2 composite coatings consists of both fully melted regions and partially melted regions, and the fully melted region has a lamellar-like structure. Phase transformations from mainly stable a-Al2O3 and anatase-TiO2 in the powders to predominant rnetastable y-Al2O3, rutile-TiO2 and Al2TiO5 phase in the Al2O3-TiO2 composite coatings were observed. It was determined that the pore content decreased with the increased in the TiO2 powder rate. The microhardness of the coating layers was 3-4.5 times higher than substrate material. The average microhardness values of the coatings were found to reach 650-860 HV.