TOOL WEAR ANALYSIS OF 22MNB5 BORON STEEL CUTTING TOOLS IN ALUMINIUM ALLOY MACHINING UNDER LUBRICATED AND UNLUBRICATED CONDITIONS

Mohd Fairuz Mohd Rashid; Mohd Hadzley Abu Bakar; Mohd Fauzi  Mamat; Lailatul Harina Paijan; Nor Ana Rosli; Shaiful Anwar Ismail; Safarudin Gazali Herawan

Mohd Fairuz Mohd Rashid Petroleum Safety Division, Department of Safety and Health Malaysia, Pusat Pentadbiran Kerajaan Persekutuan, Blok Setia Perkasa 4, Kompleks Setia Perkasa, Presint 1, 62530 Putrajaya, Malaysia.
Mohd Hadzley Abu Bakar Faculty of Industrial and Manufacturing Technology and Engineering Universiti Teknikal Malaysia Melaka (UTeM), Hang Tuah Jaya,76100 Durian Tunggal, Melaka, Malaysia.
Mohd Fauzi Mamat Universiti Teknikal Malaysia Melaka (UTeM), Hang Tuah Jaya,76100 Durian Tunggal, Melaka, Malaysia.
Lailatul Harina Paijan Universiti Teknikal Malaysia Melaka (UTeM), Hang Tuah Jaya,76100 Durian Tunggal, Melaka, Malaysia.
Nor Ana Rosli Universiti Teknikal Malaysia Melaka (UTeM), Hang Tuah Jaya,76100 Durian Tunggal, Melaka, Malaysia.
Shaiful Anwar Ismail Universiti Teknikal Malaysia Melaka (UTeM), Hang Tuah Jaya,76100 Durian Tunggal, Melaka, Malaysia.
Safarudin Gazali Herawan Industrial Engineering Department, Faculty of Engineering, Bina Nusantara University, 11480, Jakarta, Indonesia

Keywords: 22MnB5, machining, tool wear, tool life, built-up edge, flank wear

Abstract

This study explores the potential of 22MnB5 boron steel as a cutting tool material for machining AA6061 aluminium alloy under lubricated and unlubricated conditions. Conventional high-speed steel (HSS) tools often face rapid wear and limited hot hardness at high cutting speeds, while carbides and ceramics, though effective, are costly or brittle. To address this gap, four 22MnB5 samples with different hardness levels (45.5–70 HRC) were prepared through hot stamping and heat treatment. Hardness tests, ball-on-disc wear experiments, and machining trials were conducted at cutting speeds ranging from 100 to 450 m/min with a constant feed of 0.1 mm/rev and depth of cut of 0.5 mm. The heat-treated sample (70 HRC) showed the best tribological performance, achieving the lowest coefficient of friction (0.2114) and superior wear resistance. Machining trials revealed that lubrication reduced tool wear by an average of 15.8 %, while the most stable performance occurred at cutting speeds of 200-350 m/min. Wear mechanisms varied with speed and condition, shifting from built-up edge formation at lower speeds to tribolayer effects at higher speeds. Overall, the findings suggest that 22MnB5 boron steel, particularly in its heat-treated form, provides a durable and cost-effective alternative to HSS, with promising potential for sustainable machining applications.