Acoustic and Mechanical Performance of Cu-Si Alloys for Application in Temple Bells

Bronze (Cu-Sn) alloys have long been used as the standard material for constructing temple bells because of their superior strength and acoustic properties. However, due to the rising cost of tin, alternative materials for the production of temple bells have been sought after in both academia and industry. Cu-Si alloys containing 2.0, 4.0, 6.0, and 8.0 wt% Si were fabricated by casting and evaluated in terms of their mechanical, structural and acoustic properties compared with a conventional Cu-15.5 wt% Sn alloy. Tensile strength, yield strength, elastic modulus, impact toughness, and hardness were measured alongside natural frequency and damping ratio. The results show that increasing Si content up to 6.0 wt% leads to enhanced strength, increased natural frequency, and reduced damping ratio, while Si content of 8.0 wt% results in brittle microstructural features and degraded performance. Overall, Cu-6.0 wt% Si exhibited mechanical properties superior to or comparable with Cu-15.5 wt% Sn alloy, alongside a higher-pitched, longer-lasting sound.