Armour: Materials, Theory, and Design

499 Pages·2022·20.416 MB·English

by  Paul J. Hazell

Armour
Updated throughout for the new edition, Armour: Materials, Theory, and Design
covers extant and emergent protection technologies driving advances in armour sys-
tems. Covering materials, theory and design, the book has applications in vehicle,
ship, personnel and building use.
Introducing a wide range of armour technologies, the book is a key guide to the
technology used to protect against both blasts and ballistic attacks. Chapters cover
bullets, blasts, jets and fragments, as well as penetration mechanics. The new edition
builds on the previous, discussing ceramics and metallic materials as well as woven
fabrics and composite laminates. Detailing modern technology advancements, the
second edition has also been expanded to include improved explanations on shock
mechanisms and includes significantly more figures and diagrams.
An essential guide to armour technology, this book outlines key ways to imple-
ment protective strategies applicable to many types of conflict.

Armour
Materials, Theory, and Design
Second Edition
Paul J. Hazell
Cover image: Shaped charge jet penetration of armour showing the formation of behind armour
debris (courtesy of J Backofen Jr) - see Figure 11.7.
Second edition published 2023
by CRC Press
6000 Broken Sound Parkway NW, Suite 300, Boca Raton, FL 33487-2742
and by CRC Press
4 Park Square, Milton Park, Abingdon, Oxon, OX14 4RN
CRC Press is an imprint of Taylor & Francis Group, LLC
© 2023 Paul J. Hazell
First edition published by CRC Press 2015
Reasonable efforts have been made to publish reliable data and information, but the author and
publisher cannot assume responsibility for the validity of all materials or the consequences of
their use. The authors and publishers have attempted to trace the copyright holders of all material
reproduced in this publication and apologize to copyright holders if permission to publish in this
form has not been obtained. If any copyright material has not been acknowledged please write and
let us know so we may rectify in any future reprint.
Except as permitted under U.S. Copyright Law, no part of this book may be reprinted, reproduced,
transmitted, or utilized in any form by any electronic, mechanical, or other means, now known
or hereafter invented, including photocopying, microfilming, and recording, or in any information
storage or retrieval system, without written permission from the publishers.
For permission to photocopy or use material electronically from this work, access www.copyright.
com or contact the Copyright Clearance Center, Inc. (CCC), 222 Rosewood Drive, Danvers, MA
01923, 978-750-8400. For works that are not available on CCC please contact m pkbookspermissions@
tandf.co.uk
Trademark notice: Product or corporate names may be trademarks or registered trademarks and are
used only for identification and explanation without intent to infringe.
ISBN: 9780367419714 (hbk)
ISBN: 9781032345413 (pbk)
ISBN: 9781003322719 (ebk)
DOI: 10.1201/9781003322719
Typeset in Times
by codeMantra
Dedicated to all the brave men and women of the military services
who risk their lives in the defence of their nation.

Contents
Preface to the First Edition ......................................................................................xv
Preface to the Second Edition ................................................................................xvii
Author .....................................................................................................................xix
Chapter 1 Introduction ..........................................................................................1
1.1 Lessons from Nature .................................................................2
1.2 Survivability and Onions ...........................................................2
1.3 Some Basic Concepts ................................................................3
1.4 The Disposition of Armour .......................................................5
1.5 Early Applications .....................................................................6
1.5.1 Personal Protection .......................................................6
1.5.2 Vehicle Armour ............................................................7
1.5.3 Aircraft Armour ...........................................................8
1.5.4 Ship Armour .................................................................8
1.5.5 Fortifications...............................................................11
1.6 Early Empirical Models of Penetration ...................................12
1.7 Summary .................................................................................14
Notes .................................................................................................14
References ..........................................................................................14
Chapter 2 An Introduction to Materials ..............................................................17
2.1 Introduction .............................................................................17
2.2 A Quick Introduction to the Structure of Materials ................17
2.2.1 Mechanisms of Plastic Deformation ..........................18
2.3 Stress and Strain ......................................................................19
2.4 Elasticity ..................................................................................23
2.5 Strength ...................................................................................25
2.6 Hardness ..................................................................................31
2.7 Dynamic Behaviour of Materials ............................................33
2.7.1 Charpy Impact Test ....................................................35
2.7.2 Instrumented Drop Tower Test ...................................36
2.7.3 Split-Hopkinson Pressure Bar Test .............................36
2.7.4 Taylor Test ..................................................................39
2.7.4.1 Introductory Concepts ................................41
2.7.4.2 Approximate Formula for Estimating
the Yield Point ............................................42
2.7.5 Dynamic Extrusion Test .............................................46
2.7.6 Flyer-Plate Test ...........................................................47
2.8 Summary .................................................................................48
References ..........................................................................................49
vii
viii Contents
Chapter 3 Bullets, Blast, Jets and Fragments ......................................................51
3.1 Introduction .............................................................................51
3.2 Small-Arms Ammunition ........................................................51
3.2.1 Bullet Notation ...........................................................52
3.2.2 Penetrability ...............................................................52
3.2.3 The Effect of the Bullet’s Jacket during
Penetration ..................................................................55
3.3 Higher-Calibre KE Rounds .....................................................57
3.3.1 Depleted Uranium Penetrators ...................................58
3.3.2 Lethality Calculations Using the Lanz–Odermatt
Equation .....................................................................59
3.4 Explosive Materials .................................................................64
3.4.1 Blast ............................................................................65
3.4.2 Blast Wave Parameters ...............................................66
3.4.3 Blast Scaling Laws .....................................................68
3.4.4 Predicting Blast Loading on Structures .....................71
3.4.5 Blast Wave Interactions ..............................................75
3.4.6 Underwater Blasts ......................................................76
3.4.7 Buried Mines and IEDs ..............................................79
3.5 Shaped Charge .........................................................................81
3.5.1 Penetration Prediction ................................................82
3.5.2 Jet Formation ..............................................................83
3.6 Explosively Formed Projectiles ...............................................89
3.7 High-Explosive Squash Head ..................................................91
3.8 Fragments ................................................................................92
3.8.1 Gurney Analysis to Predict Fragment Velocity .........93
3.8.2 Fragment Size Predictions ..........................................99
3.8.3 Drag on Fragments and Other Projectiles ................100
3.8.4 Fragment Penetration ...............................................103
3.9 Summary ...............................................................................106
Note ...............................................................................................106
References ........................................................................................106
Chapter 4 Penetration Mechanics .....................................................................109
4.1 Introduction ...........................................................................109
4.2 Failure Mechanisms ..............................................................109
4.3 Penetration Analysis ..............................................................110
4.3.1 Penetration Analysis into Thick Plates.....................114
4.3.1.1 Robins–Euler Penetration Formula
(Robins, 1742) ...........................................114
4.3.1.2 Poncelet Penetration Formula
(Poncelet, 1829) ........................................116
4.3.1.3 Poncelet with Increasing Complexity .......118
4.3.1.4 Poncelet with a Physical Force
Definition ..................................................118
4.3.1.5 Other Related Penetration Models ............119
Contents ix
4.3.1.6 Awerbuch and Bodner Formulae ..............120
4.3.1.7 Jacobson Penetration Formulae ................127
4.3.1.8 Recht Penetration Formulae .....................132
4.3.1.9 Forrestal Penetration Formula ..................140
4.3.2 Penetration of Finite-Thickness Plates .....................149
4.3.2.1 Ballistic Limit Equations for
Finite-Thickness Plates .............................151
4.3.2.2 The Effect of Projectile Shape on
Penetration ................................................156
4.3.2.3 Penetration of Thin Plates by
Blunt-Nosed Projectiles ............................157
4.3.2.4 Penetration of Thin Plates by
Sharp-Nosed Projectiles ...........................160
4.3.3 Introducing Obliquity ...............................................163
4.3.4 Perforation of Oblique Plates of Finite
Thickness by Rods ...................................................166
4.3.5 Minimum Target Obliquity to Induce Rod
Ricochet ....................................................................167
4.4 Penetration of Rods into Thick Plates ...................................168
4.5 Hydrodynamic Penetration ....................................................169
4.5.1 Fluid Jet Penetration Model .....................................172
4.5.2 Improvements on the Fluid Jet Penetration Model ...176
4.5.3 Segmented Penetrators .............................................185
4.6 Summary ...............................................................................186
Note ...............................................................................................187
References ........................................................................................187
Chapter 5 Stress Waves .....................................................................................191
5.1 Introduction ...........................................................................191
5.2 Calculation of the Particle Velocity .......................................191
5.3 Elastic Waves .........................................................................193
5.3.1 Elastic Wave Transmission and Reflection
at an Interface ...........................................................193
5.4 Inelastic Waves ......................................................................201
5.4.1 Inelastic Wave Transmission and Reflection
at an Interface ...........................................................202
5.5 Shock Waves ..........................................................................203
5.5.1 An Ideal Shock Wave ...............................................205
5.5.2 Are Shock Waves Relevant in Ballistic-Attack
Problems? .................................................................205
5.6 Rankine–Hugoniot Equations ...............................................207
5.6.1 Conservation of Mass ...............................................208
5.6.2 Conservation of Momentum .....................................208
5.6.3 Conservation of Energy ............................................209
5.6.4 A Consistent Set of Units .........................................212
5.7 The Hugoniot .........................................................................212