Microstructural characterization of Co-based coating deposited by low power pulse laser cladding

Laser Cladding of Ultra-Thin Nickel-Based Superalloy Sheets

“…It can be seen that the orientation of the elongated grains is, in both cases, perpendicular to the boundary of the melt pool and that the grains do not have any crystallographic preferred orientation. The elongation of the grains in the direction perpendicular to the melt pool agrees with the findings of Ocelík et al [ 5 ] and Farnia et al [ 10 ]. In contrast to these publications, in this work, the highly-longitudinal orientated grains occupied more than 70% of the clad height in the crosswise sections instead of approximately 20% [ 5 ], or 50% [ 10 ].…”

“…The elongation of the grains in the direction perpendicular to the melt pool agrees with the findings of Ocelík et al [ 5 ] and Farnia et al [ 10 ]. In contrast to these publications, in this work, the highly-longitudinal orientated grains occupied more than 70% of the clad height in the crosswise sections instead of approximately 20% [ 5 ], or 50% [ 10 ]. This difference is attributed to two facts: due to the low heat dissipation into the thin substrate, the grains tend to grow in the direction perpendicular to the surface, and in addition to this, a conventional continuously-pulsed cladding method was used in these studies and the elongated grains were, thus, inclined to the cladding direction [ 5 , 10 ].…”

“…The microstructure of the substrate did not change in area 1 and no distinct heat-affected zone can be seen. This is in contrast to thicker substrates and higher laser power, in which heat affected zones are observed [ 7 , 10 ]. In the molten, and then solidified, area 2, the grains are slightly smaller than in the substrate, with an average grain diameter of about 7 µm.…”

“…Published studies typically focus on the investigation of coatings produced on rather massive cylinders [ 5 , 6 ] or plates [ 7 , 8 , 9 ] as substrates. To our knowledge, only relatively few studies have been carried out on substrates thinner than 10.0 mm [ 10 , 11 ].…”

Effect of nano-CeO2 on microstructure and wear resistance of Co-based coatings

“…They are usually used as abrasive resistant material for industrial applications in the energy, petrochemical, metallurgy, aerospace field, etc. [9][10][11][12]. Nano-materials have small size effect and high specific surface effect.…”