| Summary: | Metal forming is one of the foremost widespread techniques that is used for production. Lubrication and friction conditions affect the outcome of deformation during the metal forming process. Acknowledged as possible replacements for mineral oil-based lubricants, bio-oil lubricants have gained rising attention, as they play a crucial role in resolving environmental issues. In a Coulomb–Tresca friction model, a ring compression test was used to investigate the relationship between the Coulomb friction coefficient and Tresca shear friction. This article is presented as a case study in highlighting and modelling the use of different types of palm oil-based as a biolubricant in the cold-forging process using experimental and finite element methods. The findings show that the relationship of k behaves as a parabolic function when the friction is low (m < 0.65) and as an exponential function when the friction is high (m > 0.75), with a transitional area between the two conditions. From the result of the lubricant sample, palm stearin (PS) has demonstrated the lowest friction at m = 0.10 / µ = 0.05, compared to commercial metal-forming oil (m = 0.15 / µ = 0.075). The improvement of friction did not help in reducing the surface roughness (Ra) where palm mid olein had the lowest Ra value, although the friction that occurred during the test was high (m = 0.20 / µ = 0.09375). Palm kernel oil (PKO) has the highest friction value (m = 0.45 / µ = 01,875) compared to the other samples.
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