Initial results for the failure strength of a LOVA gun propellant at high pressures and various strain rates

Conference · Mon Apr 01 04:00:00 EST 1985

OSTI ID:5846222

Costantino, M; Ornellas, D

We present the initial results for the failure strength of a LOVA gun propellant at high pressures and various strain rates. We believe these to be the first such data for these conditions. Right circular cylinder samples are loaded hydrostatically to pressures of up to 400 MPa (60,000 psi) then, holding this confining pressure constant, an additional axial load is applied to create a shear stress. Shear stress as a function of axial strain is measured and values at 3% and 5% axial strain are reported at strain rates of 10/sup -4/, 10/sup -2/, 10/sup -1/, and 10/sup 3/ s/sup -1/ at various confining pressures to 400 MPa. The strength at 10/sup -4/ s/sup -1/ increases by more than a factor of six over 400 MPa with an increasing slope. Similar rates of increase are found for strain rates of 10/sup -2/ and 10/sup -1/ s/sup -1/. We are unaware of this type of behavior in any other material. At 0.1 MPa confining pressure, the strength increases by almost a factor of 5 as the strain rate increases from 10/sup -4/ to 2.6(10/sup 3/) s/sup -1/. The implications of these data to gun propellant grain design and the vulnerability of LOVA propellants are discussed.

• Research Organization: Lawrence Livermore National Lab., CA (USA)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 5846222
• Report Number(s): UCRL-92441; CONF-8504125-1; ON: DE85010941
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420500* -- Engineering-- Materials Testing
GUNS
MECHANICAL PROPERTIES
PROPELLANTS
STRAINS
VERY HIGH PRESSURE