The phrase "copper alloy" refers to a material made by combining copper with one or more other metals. It means that copper is mixed with different elements to create a stronger and more durable material. Full definition
The square brick paw charm is made of copper alloy. (iheartcats.com)
Use standard double edge blades, durable plated with over the heavy copper alloy body. (amazon.com)
These models are all twist to open or butterfly style and are constructed of a heavy copper alloy that makes them look and feel like many more expensive models. (primandprep.com)