The interconnected porosity of the Cr3C2–NiCr coatings obtained by high-velocity oxy fuel spraying is detrimental in corrosion and wear resistance applications. Laser treatments allow sealing of their surfaces through melting and resolidification of a thin superficial layer. A Nd:YAG laser beam was used to irradiate Cr3C2–NiCr coatings either in the continuous wave mode or at different repetiti...

Modern gas turbine hot sections need to be protected from elevated temperature and damaging environments. This protection starts as a typically two layer coating system, the base layer or bond coat (BC) acts as a corrosion barrier and a kind of buffer for the thermal mismatch between the base material and the second top thermally protective layer or Thermal Barrier Coating (TBC). The BC is norm...

The U.S. Department of Energy (DOE) Office of Fossil Energy is intensely promoting research and development of oxy-fuel combustion systems that employ oxygen, instead of air, for burning the fuel. The resulting flue gas primarily consists of H2O and CO2 that facilitates sequestration of CO2 or use it in a turbine to generate electricity, thereby leading to reduction in CO2 emissions. Also, as t...

High-velocity oxy-fuel (HVOF) spray coating plays a major role in many surface treatment methods, which tend to improve erosion and corrosion resistance properties. HVOF is well known for its dense high-quality ability. This due the less in-flight exposure time, tends have oxide content because of high-velocity Among number process parameters, porosity hardness are predominant factors while con...

In this work, a model for the nitrogen chemistry in the oxy-fuel combustion of pulverized coal has been developed. The model is a chemical reaction engineering type of model with a detailed reaction mechanism for the gas-phase chemistry, together with a simplified description of the mixing of flows, heating and devolatilization of particles, and gas solid reactions. The model is validated by co...

Compositional alterations to high-entropy alloys (HEAs) allow further evolution of these materials by adjusting their property profiles. This way, they can be used for coating technologies and surface-protection applications. In the present work, minor quantities non-metallic alloying constituents, BSiC, were added CrFeNi base system. The alloy development was carried out in an electric arc fur...

The aim of this study was to determine the kinetic parameters of the oxy-fuel combustion of char from a Brazilian bituminous coal with a high ash content. The char, with a particle diameter of 715 μm, was prepared in a N2 atmosphere at 1173 K. The oxy-fuel combustion assays were performed using a thermobalance at different temperatures and O2/CO2 gas mixtures of different concentrations. Accord...