Extreme pressure properties of nanolubricants for metal-forming applications

Purpose - The purpose of this paper is to evaluate the extreme pressure properties of CuO and TiO ₂ nanoparticle additives with the incorporation of a surfactant within a synthetic fluid for metal-forming applications. Design/methodology/approach - The paper studies the effect of CuO and TiO ₂ nanoparticle additives at various concentrations (0.01, 0.05 and 0.10 wt. per cent) in a synthetic lubricant fluid under extreme pressure conditions. Oleic acid surfactant is added to the nanolubricant to improve dispersion and stability of nanoparticles. Extreme pressure tribological tests are performed on a four-ball T-02 tribotester according to the ITEePib Polish method for testing lubricants under conditions of scuffing. Findings - The results show that the addition CuO and TiO ₂ nanoparticles under the presence of OA resulted in an increase of the load-carrying capacity (poz) of the lubricant up to 137 and 60 per cent, respectively. The seizure load was also increased by 50 and 15 per cent, respectively. Practical implications - The results show that CuO and TiO ₂ nanoparticles can be successfully used as additives improving extreme pressure properties of lubricants. Originality/value - This demonstrates the potential of nanoparticle additives using surfactants for improving the extreme pressure properties of lubricants. These nanolubricants can be used for metal-forming applications like deep-drawing, achieving an increased tool life.