Abstract: Low friction material particularly adapted for use at high temperatures in the regenerator portion of gas turbine engines, the material comprising a work surface layer on a substrate, the work surface layer prior to a break-in period comprising an iron oxide (wustite--FeO, magnetite--Fe.sub.3 O.sub.4, or hematite--Fe.sub.2 O.sub.3) matrix containing an interspersed trapping material in the interstices thereof, the trapping material comprising an inorganic compound such as a salt or oxide; and subsequent to the break-in period, the work surface layer acquires a substantially continuous film of hematite--Fe.sub.2 O.sub.3 iron oxide in which the hexagonal Fe.sub.2 O.sub.3 crystals or cells provide a highly oriented structure. Transfer of the oriented film to the mating surface occurs during run-in.

Abstract: Diffusion-alloying of aluminum into copper brazed joints and structures, particularly for turbine engine regenerator cores.