Nanoaluminum for Solid Rocket Propulsion:An Opinion

Status Nano-sized Aluminum(nAl)powders intended for rocket propulsion were first prepared at the Semenov Institute of Chemical Physics(ICP,Moscow,Russia)in 1959.Because of its favorable properties,Al is widely used to augment performance in particular of AP/HTPB(Ammonium Perchlorate/Hydroxyl-Terminated PolyButadiene)composite propellants,the workhorse of space launcher solid motors.The first propellant samples loaded with nAl were burned at ICP in 1970.Results pointed out an increased steady burning rate by ≈50％and Vieille pressure exponent by ≈ 10％,while a decrease was observed of the Al condensed combustion products(CCPs)average size.These remarkable ballistic effects prompted excitation in solid rocket practitioners.Larger energy densities,quicker energy release rates,and mitigation of two-phase(2P)flow losses compared to conventional ingredients were anticipated.Intense research and development programs started worldwide.In addition to the propellants of the widely used AP/HTPB/Al family,also new formulations were investigated:for example,the unique nAl/ice propellant(also known as ALICE).