Optimization of wear rate in tungsten-copper metal matrix composites: a robust design approach

Introduction. Wear is a critical factor in assessing the performance and durability of tungsten-copper (W-Cu) composites. These composites are widely used in electrical contacts, electrodes, and high-temperature applications. Tungsten provides high hardness and wear resistance, while copper ensures excellent electrical and thermal conductivity. The purpose of the work. This study aims to quantify the wear rate based on pin mass loss and to develop a statistically robust procedure for minimizing the dry-sliding wear rate of W-Cu metal matrix composites. The investigation focuses on determining the optimal process parameters for achieving minimal wear. The methods of investigation. In this study, a Taguchi L9 orthogonal array was employed to design the experiments, with the following key parameters: reinforcement percentage (20–40%), temperature (160–200 °C), and load (80–100 N). Wear tests were conducted using a pin-on-disc tribometer. The results were analyzed using the signal-to-noise (S/N) ratio approach (smaller-the-better characteristic) and analysis of variance (ANOVA). The experiments followed the 'One Variable At A Time' (OVAT) principle, varying only one parameter while keeping the others constant. Furthermore, ANOVA was used to assess the individual influence of each control factor – reinforcement percentage, temperature, and load – on the wear performance of the W-Cu composites. Results and Discussion. The experimental results were analyzed using signal-to-noise (S/N) ratios (smaller-the-better characteristic) and analysis of variance (ANOVA). The optimum parameter combination – 30% reinforcement, 200°C, and 80N – resulted in the lowest wear rate of 3.498×10-7 mm³/(N•m). ANOVA identified temperature as the most influential factor, contributing 90.6% to the performance variation, followed by reinforcement percentage (7.5%) and load (1.8%). Validation experiments confirmed the prediction accuracy, with an error of 4.6%. This study demonstrates the effectiveness of the Taguchi method in identifying a robust set of process parameters for enhancing the wear performance of W-Cu composites, offering practical guidance for industrial applications.