A review of tool wear and its effect on surface integrity of Inconel 718

Inconel 718 is a nickel-based superalloy widely used in aerospace, energy and automotive sectors due to its exceptional high-temperature strength and corrosion resistance. However, its low thermal conductivity, high cutting forces and work-hardening tendency pose considerable challenges during machining, often accelerating tool wear and impairing surface integrity. This review systematically analyses published research to evaluate the influence of tool wear on surface characteristics and mechanical performance during conventional machining of Inconel 718. The findings reveal that cutting parameters and thermomechanical loads drive wear mechanisms such as abrasion, diffusion, adhesion and thermal fatigue, which significantly affect surface roughness, residual stresses and subsurface microstructure. Mitigation strategies, including advanced coatings, high-pressure and hybrid cooling and minimum quantity lubrication, are examined for their effectiveness and limitations. The findings indicate that although significant progress has been achieved, industrial adoption of advanced solutions remains limited. The review concludes by emphasizing the need for real-time wear monitoring, AI-driven process optimization and sustainable lubrication and tooling technologies to achieve reliable, cost-effective and environmentally compatible machining of Inconel 718.