III.21Maraging steels

– Maraging steels are iron alloys, generally characterised by high nickel content, carbon content of less than or equal to 0,03 % by weight, and the use of substitutional elements or precipitates to produce strengthening and age-hardening of the alloy. They are subjected to heat treatment cycles to facilitate the martensitic transformation process (solution annealed stage) and subsequently age hardened (precipitation hardened stage).– Maraging steels, useable in 'missiles' (complete rocket systems and unmanned aerial vehicle systems capable of a range exceeding 300 km), having all of the following:(i) Having an ultimate tensile strength, measured at 293 K (20 °C), equal to or greater than 0,9 GPa in the solution annealed stage; or 1,5 GPa in the precipitation hardened stage;(ii) Any of the following forms:– Sheet, plate or tubing with a wall or plate thickness equal to or less than 5,0 mm; or– Tubular forms with a wall thickness equal to or less than 50 mm and having an inner diameter equal to or greater than 270 mm.