Microstructural and tribological properties of AA 1050 alloy reinforced with Ni-Cu-Fe using friction stir deposition for brake calipers

Brake calipers play a critical role in vehicle braking systems but often face many problems such as uneven brake wear, continuous friction between the brake pads and rotor which result in overheating, high wear rates, changes in the coefficient of friction COF and loss in the weight. To address these challenges, advanced manufacturing methods were used to fabricate innovative brake calipers. A novel Ni + Cu + Fe mixture, coated with Ag, was prepared via planetary ball milling and incorporated into AA1050 aluminum using additive friction stir deposition (AFSD). Then, scattering of these mixtures as cladding to fabricate simple wall structure inside AA1050 to form multi-layers single-track deposition through AFSD technique. Tribological performance was evaluated using a pin-on-disk wear test under varying loads (10-30 N) and sliding velocities (0.5-1.5 m/s). Microstructural analyses revealed uniform dispersion and strong bonding of reinforcement particles, particularly in samples with 80% Ni coated with Ag. This composition minimized wear rates to 3.2 x 10-5 mg/m under the most severe test conditions, with improved grain structure and reduced porosity. In conclusion, the usage of mechanical alloying and AFSD proves to be effective techniques for crafting brake calipers endowed with exceptional tribological properties.