Recycling Cu-Sn-Pb Alloy with Enhanced Properties from Waste Photovoltaic Welding Strip by Induction Melting

There are currently two commonly used ways to recover copper alloys from waste photovoltaic welding strips, such as acid washing and high-temperature oxidation, during which a large amount of waste gas, waste water, and various oxides will be generated. In this work, a unique approach to recycling waste photovoltaic welding strips is proposed by introducing induction melting of the waste photovoltaic ribbon for designing Cu-Sn-Pb alloys. The microstructure, microhardness, tensile properties, electrochemical performance, and friction of recycled Cu-Sn-Pb alloys from waste photovoltaic welding strips have been investigated. The results show that, with the increase of tin content, the size of the precipitated lead phase increases from 2.2 µm to 13.6 µm, the solid-solution-strengthening effect increases, the microhardness of the alloy increases from 113 HV to 146 HV, and the tensile strength increases from 628 MPa to 654 MPa. The existence of brittle phase Cu₁₀Sn₃ in the alloys leads to the decrease of the ductility and the acceleration of wear in the friction process. Both 6% Sn and 10% Sn alloys exhibit polarization potentials at approximately − 0.14 V. This discovery provides a potential approach to recycling Cu-Sn-Pb alloys from waste photovoltaic welding strips.