Impact Temperature in Splat and Splat-Substrate Interface in HVOF Thermal Spraying
— An explicit axisymmetrical FE methodology is developed here to study the particle temperature arising in WC-Co particle on an AISI 1045 steel substrate. Parameters of constitutive Johnson-cook model were used for simulation. The results show that particle velocity and kinetic energy have important role in temperature arising of particles.
Potential of High Velocity Oxy Fuel Thermal Spraying in Turbine Shaft Repairing
In this paper, the application of thermal spray coatings in high speed shafts by a revolution up to 23000 RPM has been studied. The agglomerated WC-12Co powder was coated on gas compressor components using high velocity oxy fuel (HVOF) method and its microstructure and residual stress were evaluated. Two high speed shafts were coated using the experimental data and the results demonstrated an acceptable performance in the high cycles. The results have shown that the developed coating has 148±30 MPa using hole drilling method and 156-257 MPa compressive residual stresses in curvature method. Morphological and crystallographical studies were conducted using optical microscopy, scanning electron microscopy (SEM) and X-ray diffraction respectively to evaluate the powder and coating characteristics. [M. Jalali Azizpour, S. Norouzi, E. Pipelzadeh, D.Sajedipour, H.Talebi, A.Ghamari, b.Aslani. Potential of High Velocity Oxy Fuel Thermal Spraying in Turbine Shaft Repairing. Journal of American Science 2011;7(10):69-73]. (ISSN: 1545-1003). http://www.americanscience.org. Keywords—Hole drilling, Residual stress, WC-12Co, Thermal spraying.
Finite Difference Modeling on the Temperature Field of Substrate in Friction Surfacing
Friction surfacing is an advanced process of great potential, especially in the field of repair and reclamation of worn and damaged components. As a kind of thermal processing technology, the temperature profile and changes of the substrate in friction surfacing are important factors to get coatings of high quality. In this paper, the temperature field of the substrate during the process is simulated by finite difference method. The results are consistent with experiments, reappearing the temperature change of the substrate during friction surfacing, allowing further study on figuration and quality of coatings.