A material includes a transparent substrate coated with a stack of thin layers acting on infrared radiation including at least one functional layer. The stack includes a protective coating deposited above at least a part of the functional layer. The protective coating includes at least one lower protective layer based on titanium and zirconium, these two metals being in the metal, oxidized or nitrided form, and at least one upper protective layer of carbon, within which layer the carbon atoms are essentially in an sp2 hybridization state, located above the layer based on titanium and zirconium.