Coated article and method for making the same

A method for making a coated article, comprising:

• providing an aluminum or aluminum alloy substrate;
• forming a combined gradient layer on the substrate by vacuum sputtering, using nitrogen and oxygen as reaction gases and using aluminum target;
• the combined gradient layer comprising a plurality of aluminum-oxygen-nitrogen layers, the atomic percentage of aluminum atoms within the combined gradient layer being gradually decreased from near the substrate to far away the substrate, the atomic percentages of oxygen atoms and nitrogen atoms within the combined gradient layer being gradually increased from near the substrate to far away the substrate;
• and
• forming a decorative layer on the combined gradient layer by vacuum sputtering, the decorative layer being a non-metallic layer.