Research on microstructure transformation and property of 18Cr–0.2C Fe-based coatings

ABSTRACT

In this study, the coatings were fabricated on the 3Cr13 stainless steel substrate by laser cladding. The microstructure, phase compositions and the detailed information about the crack propagation of the coatings were investigated systematically. A comparative study on the corrosion resistance of the traditional of 3Cr13 stainless steel and laser cladding blades was conducted. The standard Gibbs free energy variation of carbides, phase composition and precipitation sequence were precisely calculated. The results showed that the microstructure near the fusion zone was mainly composed of cellular crystals and dendrites. Meanwhile, its microstructure had changed in the upper middle of the coatings. The calculated results showed that the phases formed at the equilibrium state consisted of α-Ferrite, σ and M23C6 carbide. In the vicinity of fusion line and the middle of the coatings, the crack distributed along α-Ferrite grain boundaries. On the top of coatings, the crack traversed the matrix and carbide.

KEYWORDS:

• Laser cladding
• 18Cr–0.2C Fe-based coatings
• microstructure transformation
• corrosion resistance
• in situ fracture

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors wish to acknowledge the financial supports of the Sailing Plan in Guangdong Province [grant number 2015YT02G090], the Innovation Platform of Hardware Knives and Nickel Alloy Additive Manufacturing Technology in Yangjiang City [grant number 2015B020221002], High-end Knives and Scissors Additive Manufacturing (3D Printing) of Engineering Technology Research Center in Guangdong Province [grant number 509153168061], Initial Construction Subsidy for New Research and Development Institutions of Yangjiang City Hardware Knives and Scissors Industry and Technology Research [grant number 611229498090].