Hardfacing alloying is one of the inevitable methods to protect the
components which are used in heavy-duty machinery. Specifically, this process is
performed to improve the tribological properties of industrially important materials,
such as AISI 304 stainless steel (SS) bushes in nuclear power plants, SS 316 control
valves in coal power plants, polycrystalline martensitic steel valve seats in steam
turbines, aluminum-based body sheet materials in the automobile, Co-based, Fe-based
and Ni-based alloys. These materials have unique advantages to use for their specific
application. However, these materials are preferred to use for hard-facing as those
alloys have poor tribological properties at the different working conditions as they are
prone to abrasive, adhesive wear and corrosion. Tribological properties, such as
hardness and wear resistance of the alloyed material, mainly depend on the proper
selection of hardfacing alloy powders, which have equal importance in the selection of
process. Colmonoy-5, Colmonoy-6, Stellite-6, Inconel-625, H13 Steel, stainless steel
420, stainless steel 304, Ti-64, IN-718, AlSiMg, Scalmalloy, SS316L and CuCrZr are
some of the important hardfacing alloy powders to enhance the tribological properties.
Laser surface treatments, Gas Tungsten Arc-based alloying and Plasma Transferred
Arc are the major hardfacing processes. Laser surface treatments are one of the most
effective surface alloying processes for enhancing materials properties due to their
unique advantages over other processes, such as flexible operation, high energy density
and chemically clean operation. Moreover, it produces good metallurgical bonding of
the alloyed region with the substrate material, minimizes the heat-affected zone (HAZ)
and forms finer microstructure. This chapter provides a detailed understanding of
various research works carried out on hardfacing alloying by laser-treated processes on
different substrates. The outcome of this chapter would be beneficial for the present
and future research based on laser-based hardfacing and also for many hardfacing
industries.
Keywords: AlSiMg, Coefficient of friction, Colmonoy powder, CuCrZr, Inconel
powder, Stellite powder, Scalmalloy, Tribological property, Wear resistance.
