Effect of Cr Additives on the Microstructures and Properties of Laser Cladded Ni₃Si

Abstract

Three compositions, (Ni75Si25)-5Cr, (Ni75Si25)-10Cr and (Ni75Si25)-15Cr, have been cladded onto Ni-based suaperalloy substrate by pre-placing laser cladding process with a 5 kW continuous wave CO2 laser. Ni75Si25 was also cladded with the same method for comparison. The process parameters have been optimized to obtain defect free claddings. The microstructure and the hardness of the cladded layers were characterized by optical microscopy, scanning electron microscopy, X-ray diffraction and microhardness measurement. The corrosion resistance of the cladded layers was measured in a sulfuric acid solution.

Microstructural Evolution and Mechanical Properties of 2D–SiCf/SiC and Hastelloy N Joints Using 82.5Au–17.5Ni Brazing Filler

“…When the temperature was elevated to 1 000 °C, the reaction was sufficient, tight, and reliable joining of SiC f /SiC was obtained. While further increasing the brazing temperature to above 1 015 °C, brittle Ni 31 Si 12 compounds occupied the brazed seam and the thickness of brazed seam was too high, leading to the obvious deterioration of the shear strength.…”

On corrosion behaviour of HVOF sprayed Ni3Si intermetallic powders

“…10 The microhardness range of 600-760 HV has been observed in laser cladded Ni 3 Si (with cast structure). 9 In the case of Ni 3 Si alloys, the presence of Ni 5 Si 2 and Ni(Si) in the microstructure increases and decreases the hardness of alloy, respectively. [5][6][7][8][9][10][11]…”

“…9 In the case of Ni 3 Si alloys, the presence of Ni 5 Si 2 and Ni(Si) in the microstructure increases and decreases the hardness of alloy, respectively. [5][6][7][8][9][10][11]…”

“…However, low ductility and high production costs of Ni 3 Si have limited the application of this alloy as a corrosion resistant material. [5][6][7][8][9][10][11][12][13] Therefore, interests in Ni 3 Si coating technologies have been on the rise in recent years.…”

“…Finally, SHS process is limited to lab scale. [9][10][11][12][13] It is possible to develop high velocity oxy-fuel (HVOF) process to fabricate Ni 3 Si coatings. During HVOF, a mixture of oxygen and a gas or liquid fuel is burned at high pressures to produce a jet flame which heats and accelerates the particles.…”