This invention relates to coatings for a metal or non-metal substrate comprising (i) a thermal sprayed bondcoat layer applied to the substrate, and (ii) a thermal sprayed ceramic layer applied to the bondcoat layer; wherein said coating has a helium leak rate of less than 6×10−6 standard cubic centimeters per second. The thermal sprayed bondcoat layer comprises an alloy of MCrAlM′ wherein M is an element selected from nickel, cobalt, iron and mixtures thereof, and M′ is an element selected from yttrium, zirconium, hafnium, ytterbium and mixtures thereof. The alloy is thermally sprayed from a powder having a mean particle size of 50 percentile point in distribution of from about 5 microns to about 100 microns. The coatings are useful for extending the service life under severe conditions, such as those associated with metallurgical vessels' lances, nozzles and tuyeres.