A self-lubricating piston for an internal combustion engine comprises a composite coating adhered to a grooved piston surface and containing therein a first reinforcing phase of high tensile strength, high modulus of elasticity, reinforcing fibers of graphitic structure and a second reinforcing phase of powdered solid lubricant. The fibers are spooled around the piston and continuous for at least two turns. The fibers are preferably contacted along their lengths with longitudinally discontinuous bands of high thermal conductivity soft material forming multiple radial heat transfer paths throughout the composite layer.