MILITARY TECHNOLOGY AR MOUR Hazell ARMOUR Materials, Theory, and Design Materials, Theor y, Highlights Recent Advances in Materials/Armour Technology and Design As long as conflict exists in the world, protection technologies will always be in demand. Armour: Materials, Theory, and Design describes the existing and emerging protection technologies that are currently driving the latest advances in A armour systems. This book explains the theory, applications, and material science R aspects of modern amour design as they are used in relation to vehicles, ships, M personnel, and buildings, and explores the science and technology used to provide protection against blasts and ballistic attacks. It covers materials technologies used in O protection; addresses the system effects of adding blast-wave shaping to vehicles, as U well as the effect on the human body; and outlines ballistic testing techniques. R Takes a Look at How Armour Works The book discusses ceramics for armour applications; transparent armour; and metals for armour applications (including aluminum alloys, magnesium alloys, titanium alloys and steels); as well as composite armour systems; explosive reactive armour systems with reference to defensive and suite for vehicles; and wound ballistics. In addition, the author lists more than 100 references for advanced study and further reading. Armour: Materials, Theory, and Design introduces a variety of armour technologies, outlines modern threats and dangers applicable to protection technology, and aids readers in implementing protective structures that can be used in battle, conflict, military zones, and other related environments. Paul J. Hazell K23217 6000 Broken Sound Parkway, NW Suite 300, Boca Raton, FL 33487 711 Third Avenue New York, NY 10017 an informa business 2 Park Square, Milton Park www.crcpress.com Abingdon, Oxon OX14 4RN, UK www.crcpress.com K23217_cover.indd 1 6/5/15 10:15 AM Materials, Theory, and Design Materials, Theory, and Design Paul J. Hazell The University of New South Wales Canberra, Australia Boca Raton London New York CRC Press is an imprint of the Taylor & Francis Group, an informa business CRC Press Taylor & Francis Group 6000 Broken Sound Parkway NW, Suite 300 Boca Raton, FL 33487-2742 © 2016 by Taylor & Francis Group, LLC CRC Press is an imprint of Taylor & Francis Group, an Informa business No claim to original U.S. Government works Version Date: 20150604 International Standard Book Number-13: 978-1-4822-3830-3 (eBook - PDF) This book contains information obtained from authentic and highly regarded sources. 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One who puts on his armour should not boast like one who takes it off. 1 Kings 20 v 11 (NIV) Contents Preface ...................................................................................................................xiii Author .....................................................................................................................xv 1. Introduction .....................................................................................................1 1.1 Survivability and Onions ....................................................................2 1.2 Some Basic Concepts ............................................................................3 1.3 The Disposition of Armour .................................................................4 1.4 Early Applications .................................................................................6 1.4.1 Personal Protection ..................................................................6 1.4.2 Vehicle Armour ........................................................................7 1.4.3 Aircraft Armour .......................................................................8 1.4.4 Ship Armour .............................................................................8 1.4.5 Fortifications ...........................................................................10 1.5 Early Empirical Models of Penetration ............................................11 1.6 Summary ..............................................................................................14 2. An Introduction to Materials .....................................................................15 2.1 Introduction .........................................................................................15 2.2 A Quick Introduction to the Structure of Materials ......................15 2.2.1 Mechanisms of Plastic Deformation ...................................16 2.3 Stress and Strain ..................................................................................17 2.4 Elasticity ...............................................................................................21 2.5 Strength ................................................................................................24 2.6 Hardness ..............................................................................................30 2.7 Dynamic Behaviour of Materials ......................................................32 2.7.1 Charpy Impact Test ...............................................................36 2.7.2 Instrumented Drop Tower Test ............................................37 2.7.3 Split-Hopkinson Pressure Bar Test ......................................37 2.7.4 Taylor Test ...............................................................................38 2.7.4.1 Introductory Concepts ...........................................39 2.7.4.2 Approximate Formula for Estimating the Yield Point ...............................................................40 2.7.5 Dynamic Extrusion Test........................................................45 2.7.6 Flyer-Plate Test .......................................................................45 2.8 Summary ..............................................................................................47 3. Bullets, Blast, Jets and Fragments .............................................................49 3.1 Introduction .........................................................................................49 3.2 Small-Arms Ammunition ..................................................................49 vii viii Contents 3.2.1 Bullet Notation .......................................................................50 3.2.2 Penetrability ............................................................................51 3.2.3 The Effect of the Bullet’s Jacket during Penetration .........53 3.3 Higher-Calibre KE Rounds ...............................................................54 3.4 Explosive Materials .............................................................................55 3.4.1 Blast ..........................................................................................57 3.4.2 Blast Wave Parameters ..........................................................58 3.4.3 Blast Scaling Laws .................................................................60 3.4.4 Predicting Blast Loading on Structures .............................62 3.4.5 Underwater Blasts ..................................................................64 3.4.6 Buried Mines and IEDs .........................................................66 3.5 Shaped-Charge ....................................................................................68 3.5.1 Penetration Prediction ...........................................................69 3.5.2 Jet Formation ..........................................................................71 3.6 Explosively Formed Projectiles .........................................................74 3.7 High-Explosive Squash Head ............................................................76 3.8 Fragments .............................................................................................77 3.8.1 Gurney Analysis to Predict Fragment Velocity .................79 3.8.2 Drag on Fragments and Other Projectiles ..........................83 3.8.3 Fragment Penetration ............................................................87 3.9 Summary ..............................................................................................90 4. Penetration Mechanics ................................................................................91 4.1 Introduction .........................................................................................91 4.2 Failure Mechanisms ...........................................................................91 4.3 Penetration Analysis ...........................................................................92 4.3.1 Penetration into Thick Plates................................................96 4.3.1.1 Recht Penetration Formula ...................................97 4.3.1.2 Forrestal Penetration Formula ............................102 4.3.2 Penetration of Thin Plates ...................................................109 4.3.2.1 The Effect of Projectile Shape on Penetration. ......................................................109 4.3.2.2 Penetration of Thin Plates by Blunt-Nosed Projectiles ..............................................................110 4.3.2.3 Penetration of Thin Plates by Sharp-Nosed Projectiles ..............................................................112 4.3.3 Introducing Obliquity .........................................................114 4.4 Hydrodynamic Penetration .............................................................117 4.4.1 Fluid Jet Penetration Model ................................................119 4.4.2 Improvements on the Fluid Jet Penetration Model .........124 4.4.3 Segmented Penetrators ........................................................133 4.5 A Brief Look at Computational Approaches .................................134 4.5.1 Types ......................................................................................134 4.6 Summary ............................................................................................136