%0 Journal Article %A Mahe, B. %A Perut, Christian %D 1993 %I Begell House %N 1-6 %P 361-374 %R 10.1615/IntJEnergeticMaterialsChemProp.v2.i1-6.210 %T BORON PROPELLANTS FOR DUCTED ROCKET APPLICATION %U https://www.dl.begellhouse.com/journals/17bbb47e377ce023,181301e53c3359b9,54f95c9d3ad7eb70.html %V 2 %X A research program was conducted to optimize the processability and evaluate the properties of fuel-rich solid propellants heavily loaded with boron. Propellants containing large amounts of boron pose specific problems. Good manufacturing and mechanical properties require definition of the specifications for the raw material, and development of a method for the mixing operation. The maximum stress is usually between 1.4 and 2.5 MPa, and the strain at maximum stress between 35 and 50 %.
The computed volumetric specific impulses are between 1600 and 1800 s g cm−3 for a flight at Mach 2 and sea level, with a chamber pressure equal to 0.57 MPa and an equivalence ratio of 0.4. Ballistic evaluations were performed by firing end-burning grains. A large burning rate range is achieved by varying the ammonium perchlorate particle size and the ballistic catalyst content. This allows operation in the choked gas generator or in the unchoked gas generator configuration. The burning rate required at the operating pressure is between 8 and 15 mm/s for an end-burning grain. The unchoked gas generator configuration demands high burning rate propellant because of the low operating pressure. These compositions produce no combustion residue, but leave slag in the gas generator, with a mass corresponding to less than 1 % of the initial mass of the grain. %8 1993-01-01