Strain Rate Insensitivity of Damage-Induced Surface Area in M30 and JA2 Gun Propellants
Abstract
Uniaxial compression tests are performed at constant strain rate on single-grain, seven-perforated specimens of M30 and JA2 gun propellant using the US Army's high rate, servohydraulic test apparatus in order to investigate the effects of strain rate, temperature, and percent axial strain on the combustion characteristics (apparent burn rate and pressurization rate) of the propellants. At room temperature M30 primarily deforms by macroscopic fracture and JA2 deforms by macroscopic flow. The single grains of deformed propellant are then burned in a newly designed 7.8-cc mini closed-bomb and plots of pressure, pressurization rate and surface area ratio versus time, and apparent burn rate versus pressure are compared with baseline results for the undeformed propellant specimens. The apparent burn rates of damaged M30 propellant vary considerably and the degree of damage-induced surface area approaches six times that of the undeformed baseline M30 specimens. The apparent burn rates of JA2 are relatively unaffected by the induced deformation. Results of the statistical test design indicate that the apparent burn rate of JA2 at 20 MPa is primarily dependent on the deformation temperature, yet the apparent burn rate of M30 at 20 MPa is dependent primarily on percent axial specimen strain. The apparent burn rates for these propellants are relatively insensitive to the deformation strain rate over the range 0.01 to 100/sec.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1991
- Accession Number
- ADA239666
Entities
People
- Arpad Juhasz
- George A. Gazonas
- James C. Ford
Organizations
- Ballistic Research Laboratory