Scale-up of a Self-Lubricating Composite Connecting Rod Produced by Powder Metallurgy in a Pilot Plant

The optimization of tribological systems is crucial for increasing the efficiency of mechanical systems. The use of advanced materials, specifically self-lubricating composites, is an alternative to reduce mechanical losses and increase the durability of components. In this study, a connecting rod with self-lubricating material was developed, with a Fe0.5Si4Ni matrix and 6.5 vol% graphite and 1 vol% hBN as solid lubricants, using existing industrial infrastructure in the laboratory. Given the novelty of the material, we not only controlled microstructure and properties but also evaluated dimensions to ensure optimal bearing performance. Using statistical process control tools, along with microstructural and tribological analyses, we identified processing parameters to minimize dimensional variability and replicate composite properties. The results showed the technical potential of producing an industrial-level component with the self-lubricating composite, achieving a Cp close to 3.3 and a friction coefficient of 0.14.