Influence of high velocity oxy-fuel parameters on properties of nanostructured TiO2 coatings

Bulletin of materials science

Maryamossadat Bozorgtabar²  Mohammadreza Rahimipour³  Mehdi Salehi⁴  Mohammadreza Jafarpour¹ 

[1] Mobarakeh Steel Company, P. O. Box 84815-161, Isfahan, Iran$$Mobarakeh Steel Company, P. O. Box 84815-161, Isfahan, IranMobarakeh Steel Company, P. O. Box 84815-161, Isfahan, Iran$$;Islamic Azad University-Majlesi Branch, Majlesi New Town, Isfahan, Iran$$Islamic Azad University-Majlesi Branch, Majlesi New Town, Isfahan, IranIslamic Azad University-Majlesi Branch, Majlesi New Town, Isfahan, Iran$$;Materials and Energy Research Centre, P. O. Box 14155-4777, Tehran, Iran$$Materials and Energy Research Centre, P. O. Box 14155-4777, Tehran, IranMaterials and Energy Research Centre, P. O. Box 14155-4777, Tehran, Iran$$;Department of Materials Engineering, Isfahan University of Technology, Isfahan 84154, Iran$$Department of Materials Engineering, Isfahan University of Technology, Isfahan 84154, IranDepartment of Materials Engineering, Isfahan University of Technology, Isfahan 84154, Iran$$

关键词: HVOF;    TiO2;    phase transformation;    nanostructure coating.;   

DOI  :  

学科分类：材料工程

来源: Indian Academy of Sciences

【 摘 要 】

A liquid fuel high velocity oxy-fuel (HVOF) thermal spray process has been used to deposit TiO₂ nanostructured coatings utilizing a commercially available nanopowder as the feedstock. The coatings were characterized by means of X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and transmission electron microscope (TEM), respectively. Photocatalytic activity was evaluated as a rate constant of decomposition reaction of methylene blue (MB) determined from the changes of relative concentration of MB with UV irradiation time. The results indicate that the sprayed TiO₂ coatings were composed of both TiO₂ phases viz. anatase and rutile, with different phase contents and crystallite sizes. A high anatase content of 80% by volume was achieved at 0.00015, fuel-to-oxygen ratio with nanostructure coating by grain size smaller than feedstock powder. Photocatalytic activity evaluation results indicated that all the TiO₂ coatings are effective to degradation MB under UV radiation and their activities differ in different spray conditions. It is found that fuel flow rate strongly influenced on phase transformation of anatase to rutile and by optimizing the rate which can promote structural transformation and grain coarsening in coating and improving photocatalytic activity.

【 授权许可】

Unknown