Velocity Measuring Approaches for the Determination of Ballistic Limits of GLARE 5 Fiber-Metal Laminate Plates
In this study, 152.4 mm by 101.6 mm (6”×4”) GLARE 5 plates with various thicknesses were impacted by a 0.22 caliber bullet-shaped projectile using a high-speed gas gun. Velocities of the projectile along the ballistic trajectory were measured at different locations throughout the test using (1) a pair of laser-beam optoelectronic paths near the gun muzzle, (2) two sets of chronographs before and after the specimen, and (3) a high speed camera for recording the trajectory history of the projectile. The high speed camera yielded the most reliable way of measuring the projectile speed and could record the projectile orientation before and after the impact. It was experimentally detected that the measured speed of the projectile at the muzzle of the barrel was less than the actual impact speed of the projectile. The phenomenon can be explained by the well-known intermediate ballistics. The incident projectile impact velocity versus the residual velocity was plotted and numerically fitted according to the classical Lambert–Jonas equation for the determination of ballistic limit velocity, V50. The results showed that V50 varied in a parabolic trend with respect to the metal volume fraction (MVF) and the specimen’s thickness.
KeywordsFatigue Titanium Dust Helium Epoxy
Unable to display preview. Download preview PDF.
- 1.Vlot A., Glare-History of the development of a New Aircraft Material, Kluwer, Dordrecht: Kluwer Academic Publishers, 2001.Google Scholar
- 8.Langdon G.S., Nuricka G.N., Cantwell W.J., The response of fibre metal laminate panels subjected to uniformly distributed blast loading. Eur. J. Mech. A, Solids, 27, 107–115, 2008.Google Scholar
- 9.Vasek A., Polak J., Kozak V., Fatigue crack initiation in fiber-metal laminate GLARE 2. Mater. Sci. Eng., A234–236, 621–624, 1997.Google Scholar
- 11.Castrodeza E.M., Bastian F.L., Perez Ipiña J.E., Critical fracture toughness, JC and δ5C, of unidirectional fiber-metal laminates. Thin-Walled Struct., 41, 1089–1111, 2003.Google Scholar
- 14.Langdon G.S, Lemanski S.L., Nurick G.N., Simmons M.C., Cantwell W.J., Schleyer G.K., Behaviour of fiber-metal laminates subjected to localized blast loading: Part I-experimental observation. Int. J. Impact Eng., 34, 1202–1222, 2007.Google Scholar
- 17.Data sheets. Aviation Equipment Structures, Inc., Costa Mesa, California, 1998.Google Scholar
- 18.QA Reports B0319B-2, B1008B-1, B0904A-3. Structural Laminates Company, New Kensington, Pennsylvania, 1994.Google Scholar
- 19.Alloy 7475 Plate and Sheet, ACRP-053-B. Alcoa Mill Products, Bettendorf, Iowa.Google Scholar
- 20.Vlot A., Gunnink J.W. (Eds.). Fiber Metal Laminates, an Introduction. Dordrecht, the Netherlands: Kluwer Academic Publishers, 2001.Google Scholar
- 21.Farrar C.L., Leeming D.W., Military Ballistics-A Basic Manual (Battlefield Weapons Systems & Technology). Brassey’s Defence Publishers, Volume X, 1983.Google Scholar
- 22.Lambert J.P., Jonas G.H., Towards standardization of in terminal ballistics testing: velocity representation. Ballistic Research Laboratories, Aberdeen Proving Ground, Maryland, Report No. BRL-R-1852, 1976.Google Scholar