Microstructure and wear resistance of in-situ TiC–Al2O3 particles reinforced Fe-based coatings produced by gas tungsten arc cladding

• Fe–TiC–Al2O3 composite was fabricated on the surface of 1045 steel.
• The formation mechanism of the reinforcing particles was declared.
• Wear resistance of the produced composite was investigated.

ABSTRACTThe present research aimed to fabricate Fe–TiC–Al2O3 coatings on the surface of 1045 steel by gas tungsten arc cladding process. 3TiO2–4Al–(3 + x)C–yFe (x = 1.5 and 3, y = 0 and 1.71) mixtures were used as cladding precursors. The mixtures and the substrate were then melted using a gas tungsten arc cladding process. Results showed that a composite containing 20 vol.% reinforcing phases was fabricated using 3TiO2–4Al–4.5C–1.71Fe precursor. The composite coatings formed by a four-step mechanism including, the formation of TiC into the Fe particles in front of the molten pool, the entrance of the Fe particles to the weld pool, the dissolution of TiC into the melt and finally, re-precipitation of TiC during solidification separately or on Al2O3 particles. Also, incomplete dissolution of some TiC formed TiC–Al2O3 colonies in the structure of the coatings. The hardness of the coatings increased up to the maximum of 830 HV which improved the abrasive wear resistance of the substrate.