Fabrication of nano-TiC functional gradient wear-resistant composite coating on 40Cr gear steel using laser cladding under starved lubrication conditions

•A nano-TiC gradient coating with good metallurgical bonding was prepared.•Nano-TiC forms a dense and uniform microstructure inside the gradient coating.•The micro-hardness increased from 612 HV to 1088 HV along the gradient direction.•Gradient coating offers superior wear resistance to uniform coating.