Here's why:

* Metallic bonds are formed between metal atoms. They involve a "sea" of delocalized electrons that are shared by all the metal atoms in the structure. This sharing creates strong attractive forces between the positively charged metal ions and the negatively charged electron cloud.

* Covalent bonds involve the sharing of electrons between two specific atoms, typically nonmetals.

Copper, being a metal, does not form covalent bonds with other copper atoms. Instead, it forms a metallic bond, leading to its characteristic properties like good conductivity, malleability, and ductility.