Melo-Maximo L.,National Polytechnic Institute of Mexico |
Perez M.,Instituto Tecnolo Gico Y Of Estudios Superiores Of Monterrey |
Lin J.,Southwest Research Institute |
Salas O.,Instituto Tecnolo Gico Y Of Estudios Superiores Of Monterrey |
And 5 more authors.
Surface Engineering | Year: 2015
In the present work, Cr/Cr2O3 thin films were applied on 304L stainless steel substrates via modulated pulsed power magnetron sputtering to investigate their protective behaviour against metal dusting for this steel. Depositions of the films were carried out at various negative values of bias voltage. The structure of the films consisted of a very dense fine columnar structure composed of textured Cr2O3. The films showed similar, very good protective behaviour during exposition to an atmosphere of CH4zH2zresidual oxygen and moisture at 1073 K for 20 h. The main protection mechanism proposed was associated to the coatings acting as barriers for outward diffusion of the alloy elements and inward diffusion of C and O into the alloy, especially early in the exposure. © 2015 Institute of Materials, Minerals and Mining.
Valdez S.,National University of Costa Rica |
Ascencio J.,National University of Costa Rica |
Casolco S.R.,Instituto Tecnolo Gico Y Of Estudios Superiores Of Monterrey |
International Journal of Electrochemical Science | Year: 2014
Metal matrix composite (MMC) are engineered materials manufactured by the action of incorporated reinforcement materials into metal matrix. As a result, stiff and hardened reinforcing phase in metallic matrix is obtained. The matrix includes non-ferrous structures; meanwhile reinforcing phases comprise hardened non-metallic particulates. The purpose of this paper is to investigate microstructural and electrochemical behavior of Al-Mg matrix reinforced with SiC particles. The Aluminum-Magnesium matrix composite was manufactured by the vortex method. SiC particles were mixed into steel tubes at 1500 rpm to molten Al-Mg as-cast alloy. The MMC was characterized with the purpose of studying chemical and electrochemical interactions of SiC particles with the metal-matrix. Results show that anodic dissolution in the cast Al-Mg matrix was accelerated by the formation of a non-stable oxide layer exhibiting partial protection with small resistance to polarization conditions, while the corrosion phenomena in Al-MMC was inhibited by the addition of silicon carbide particles. © 2014 The Authors.