What is the difference between cold rolled aluminum coils and hot rolled aluminum coils?

Cold rolled aluminum coils are produced by rolling aluminum at room temperature, resulting in a smoother surface and tighter dimensional tolerances. They have higher strength and hardness due to cold working. Hot rolled aluminum coils, on the other hand, are rolled at high temperatures, which allows for larger thickness reductions and creates a rougher surface. Hot rolled coils are generally softer and more ductile, with lower strength and hardness compared to cold rolled coils. The choice between the two depends on the specific application requirements for strength, surface finish, and formability.