Tai ngay!!! Ban co the xoa dong chu nay!!! Automotive Steels Related titles Lightweight Composite Structures in Transport: Design, Manufacturing, Analysis and Performance (ISBN 978-1-78242-325-6) Future Development of Thermal Spray Coatings: Types, Designs, Manufacture and Applications (ISBN 978-0-85709-769-9) Pekguleryuz, Kainer and Kaya, Fundamentals of Magnesium Alloy Metallurgy (ISBN 978-0-85709-088-1) Woodhead Publishing Series in Metals and Surface Engineering Automotive Steels Design, Metallurgy, Processing and Applications Edited by Radhakanta Rana Shiv Brat Singh AMSTERDAM BOSTON HEIDELBERG LONDON NEW YORK OXFORD PARIS SAN DIEGO SAN FRANCISCO SINGAPORE SYDNEY TOKYO Woodhead Publishing is an imprint of Elsevier G G G G G G G G G Woodhead Publishing is an imprint of Elsevier The Officers’ Mess Business Centre, Royston Road, Duxford, CB22 4QH, United Kingdom 50 Hampshire Street, 5th Floor, Cambridge, MA 02139, United States The Boulevard, Langford Lane, Kidlington, OX5 1GB, United Kingdom Copyright © 2017 Elsevier Ltd All 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https://www.elsevier.com Publisher: Matthew Deans Acquisition Editor: Gwen Jones Editorial Project Manager: Charlotte Cockle Production Project Manager: Debasish Ghosh Cover Designer: Christian J Bilbow Typeset by MPS Limited, Chennai, India Contents List of contributors ix 1 Design of auto body: materials perspective J.R Fekete and J.N Hall 1.1 History of steel usage in vehicle body structures and closures 1.2 Significant events in history impacting steel application in vehicle design 1.3 Breakdown in vehicle by material mass and application 1.4 Improved safety and fuel economy: current regulations 1.5 Vehicle energy losses and contribution to fuel economy through mass reduction 1.6 Summary References Steels for auto bodies: a general overview J.N Hall and J.R Fekete 2.1 Steel grades and design strategy for auto body applications 2.2 Steel’s contribution to fuel economy through mass reduction 2.3 Recent body structure & closures production applications 2.4 Manufacturing concerns 2.5 Future steel technology 2.6 Sustainability/life cycle assessment 2.7 Summary References Formability of auto components E.H Atzema 3.1 Introduction 3.2 Basic concepts 3.3 Advanced process analysis 3.4 Basic concepts 3.5 Advanced process analysis 3.6 Forming processes 3.7 Formability aspects of different steels 1 12 16 16 19 19 25 28 31 35 37 43 44 47 47 48 48 50 63 70 82 vi Contents 3.8 Conclusions Acknowledgments References 90 90 90 Physical metallurgy of steels: an overview G Krauss 4.1 Introduction 4.2 The iron-carbon phase diagram 4.3 Austenite 4.4 Ferrite and cementite 4.5 Steel microstructure: general considerations 4.6 Steel microstructures produced by diffusion: ferrite, pearlite, and bainite 4.7 Diffusionless transformation of austenite: martensite 4.8 Transformation diagrams and Jominy End Quench Curves 4.9 Summary References 95 Deep drawable steels P Ghosh and R.K Ray 5.1 Introduction 5.2 Aluminum killed (AK) steels 5.3 Interstitial free (IF) and interstitial free high strength (IFHS) steels 5.4 Bake hardening (BH) steels 5.5 Summary and conclusions References High strength low alloyed (HSLA) steels C.I Garcia 6.1 History and definition 6.2 Structureproperty relationships: effect of microstructure on the mechanical properties of HSLA steels 6.3 Fundamental metallurgical principles of thermomechanical processing 6.4 Examples of hot and cold rolled HSLA steels used in the transportation industry 6.5 Transformation behavior 6.6 Summary References Dual-phase steels N Fonstein 7.1 Introduction 7.2 Effect of structure on mechanical properties of dual-phase steels 95 96 98 99 100 101 104 108 110 110 113 113 116 127 138 140 141 145 145 148 150 153 155 165 166 169 169 170 Contents Obtaining dual-phase steels by transformations of austenite using controlled cooling from the intercritical region 7.4 Obtaining as-rolled dual-phase microstructure by cooling of deformed austenite 7.5 Effects of chemical composition on dual-phase steels 7.6 Application of dual-phase steels in modern cars 7.7 Summary References vii 7.3 10 TRIP aided and complex phase steels K Sugimoto and M Mukherjee 8.1 Introduction 8.2 Processing route and microstructure 8.3 Alloy design 8.4 Microstructure modeling 8.5 Deformation-induced transformation of retained austenite 8.6 Mechanical properties 8.7 Press formability 8.8 Other mechanical properties 8.9 Summary References Bake hardening of automotive steels E Pereloma and I Timokhina 9.1 Introduction 9.2 Mechanisms of bake hardening response 9.3 Factors affecting bake hardening response 9.4 Bake hardening of multi-phase steels 9.5 Modeling 9.6 Effect of bake hardening on the performance of automotive steels 9.7 Summary References Bainitic and quenching and partitioning steels E De Moor and J.G Speer 10.1 Introduction 10.2 Bainitic steels 10.3 Quenching & partitioning 10.4 Substitution of silicon by aluminum 10.5 Manganese alloying 10.6 Carbon alloying 10.7 Molybdenum additions 10.8 Competing reactions during partitioning 10.9 Local formability of bainitic and Q&P steels 10.10 Conclusions 186 197 198 208 208 209 217 217 219 224 229 231 239 245 247 248 249 259 259 260 264 272 281 282 283 283 289 289 289 292 294 296 298 301 304 308 312 viii 11 12 13 Contents Acknowledgments Disclaimer References 312 313 313 High Mn TWIP steel and medium Mn steel B.C De Cooman 11.1 Introduction 11.2 High Mn TWIP steel 11.3 Medium Mn TRIP and TWIP TRIP steel 11.4 Outlook for high Mn TWIP steel and medium Mn steel 11.5 Summary Acknowledgment List of abbreviations References 317 Hot formed steels E Billur 12.1 Introduction 12.2 Physical metallurgy of hot forming steels 12.3 Hot forming steels 12.4 Blank coatings 12.5 Typical automotive applications 12.6 Summary and future outlook References Forging Grade Steels for Automotives O.N Mohanty 13.1 Introduction 13.2 Basic physical metallurgy relevant to hot forging 13.3 Evolution of microalloyed forging steels 13.4 Steels for automotive forging—the way forward References Index 317 320 352 360 379 379 379 380 387 387 392 393 398 402 405 406 413 413 417 436 447 448 455 List of contributors E.H Atzema Tata Steel, IJmuiden, The Netherlands E Billur Billur Metal Form Ltd., Bursa, Turkey; Atılım University, Ankara, Turkey B.C De Cooman Graduate Institute of Ferrous Technology, POSTECH, Pohang, South Korea E De Moor Colorado School of Mines, Golden, CO, United States J.R Fekete National Institute of Standards and Technology, Boulder, CO, United States N Fonstein ArcelorMittal Global R&D, East Chicago Labs, United States C.I Garcia University of Pittsburgh, Pittsburgh, PA, United States P Ghosh Tata Steel, Jamshedpur, India J.N Hall Steel Market Development Institute, Southfield, MI, United States G Krauss Colorado School of Mines, Golden, CO, United States O.N Mohanty RSB Group, Pune, India M Mukherjee Tata Steel Ltd., Jamshedpur, Jharkhand, India E Pereloma University of Wollongong, Wollongong, NSW, Australia R.K Ray Indian Institute of Engineering Science and Technology, Shibpur, West Bengal, India J.G Speer Colorado School of Mines, Golden, CO, United States K Sugimoto Shinshu University, Wakasato, Nagano, Japan I Timokhina Deakin University, Geelong, VIC, Australia 456 Auto bodies, steels for (Continued) welding/joining, 3334 recent body structure and closures production applications, 2831 sustainability, 3738 Auto body, design of, breakdown in vehicle by material mass and application, 89 safety and fuel economy, 912 CAFE and relationship to CO2 emissions, 1112 safety regulations, 1011 significant events in history impacting steel application in, 18 vehicle body structures and closures, history of steel usage in, vehicle energy losses and contribution to fuel economy, 1216 aluminum, 1415 carbon fiber reinforced polymers, 1516 magnesium, 15 Auto/Steel Partnership, 56 Automotive forging, steels for, 447448 Automotive quality galvanized products, Automotive sheet steel grades, 20f Avrami equation, 161 B BA AK steel, alloying elements in, 119t BA-IFHS steels, 136137 Bainite, 2021, 101103, 104f, 274275 transformation kinetics, 226, 294295 Bainite reaction, 196, 289 Bainitic ferrite matrix, 221222, 221f Bainitic heat treatments, 290t Bainitic steels, 289291 local formability of, 308312 Bake hardenable steels, 67 “Bake hardenable” grades, 24 Bake hardening (BH), 169 Bake hardening (BH) steel, 138140, 259 aluminum killed steel, 139140 bake hardening temperature and time, effect of, 271272 composition, 264266 dislocation pinning, 139 effect on performance of automotive steels, 282283 Index grain size, effect of, 270271 interstitial free steel, 140 mechanisms, 260264 precipitation hardening, 139 processing parameters, effect of, 266269 annealing temperature, 266267 cooling rate, 267268 pre-straining, effect of, 268 strain path, effect of, 269 Bake hardening response (BHR), 259264, 260f Banded ferrite-pearlite microstructures, 190 BaoSteel, 395396 Bare spots, 226, 294295 Barrier protection, 400 Batch annealed AK steels, 117121 chemical composition, importance of, 119 processing parameters, importance of, 120121 batch annealing heating rate, 121 coiling temperature, 120121 finish rolling temperature, 120 slab reheating temperature, 120 Batch annealing (BA), 67, 108, 116, 154 Battery electric vehicle (BEV), 26 Bauschinger effect, 4849, 348 Bendability, 88 Bending, 50, 7578 β-fiber orientation, 366368 Blank coatings, 398402 AlSi coating, 399400 varnish coatings, 402 Zn based coatings, 400401 Body-in-white (BIW), 2627 Body-on-frame (BOF) migration to body-frame-integral (BFI) structures, Boron, 393 Bouaziz backstress effect, 347348, 347f B-pillar, 2930, 402403 Brittle network effect, 242 Burgers vector, 331332 Buyn model, 337338 C CA-aluminum killed steels, 125127 CAFE (Corporate Average Fuel Economy), 2, Index compliance and effects, 2728 mileage requirements, 3f performance, 3f and relationship to CO2 emissions, 1112 Cahn model, 161 California Air Resources Board, CALPHAD, 323324 Carbide free bainite (CFB), 169 Carbides, 202 Carbon, 23, 95, 198, 224225, 326327, 392 Carbon alloying, 298300 Carbon equivalent, 3334 Carbon fiber reinforced polymers (CFRP), 1516, 25, 387 Carbon partitioning, 306307 Carbonitride, 202 Carbo-nitride formers, Carbonitride-forming elements, 207 Carbo-sulfide precipitates, 134 Carburized steel 8620, 429f Cellular Automata, 165 Cementite, 9697, 99100, 102103, 226 Center Body Pillar, 154 CGL (continuous galvanizing line), 196 Charger XL, Chassis frame, design of, 154f Chevrolet Colorado, 2829, 29f Chromium, 9596, 201, 207, 229, 330 on tensile properties, 205 Chrysler Corporation, Clean Air Act, 16 Close-packed plane, 99 CMnAl steel, 301304 CMnSi steel, 294295, 301304 CMnSiAl steel, 301304 CO2 emissions, 1112 CO2 emissions per vehicle weight savings, 146f Cohen-Weertman deviation process, 335336 Cohen-Weertman nucleation mechanism, 334 Coiling temperature (CT), 120121, 124125, 131 Cold forging, 413414 Cold forming, 68, 115t Cold rolling, 67 and annealing, 132 457 Cold rolling route, 220 complex phase (CP) steels, 223224 TRIP aided steels, 220 Coldrolled carbon steel flat products, 115t Cold-rolled HSLA sheet steel, 145, 147 Complex phase (CP) steels, 4748, 218f, 219, 222224, 223f See also TRIP aided and complex phase steels cold rolling route, 223224 hot rolling route, 222223 Composition-processing-microstructureproperty relationship, 150 Computer Aided Engineering (CAE), 49 Constitutive models, 165 Continuous annealing (CA), 67, 108, 116 Continuous annealing line (CAL), 183184, 220 Continuous casting process, 23 Continuous cooling transformation (CCT), 161, 191192 CCT curve, 392393, 392f CCT diagram of conventional low alloy (AISI 4137) steel, 444f of low carbon bainitic steel, 444f Continuous transformation, 108, 109f Continuously annealed AK steels, 121127 chemical composition, importance of, 122124 processing parameters, importance of, 124127 coiling temperature, 124125 cold rolling and annealing, 125127 finish rolling temperature, 124 slab reheating temperature, 124 typical annealing cycle for, 127f Conventional cold rolled steel, 24 Copley-Kear-Byun model for twinning, 332334 Copper, 440443 precipitation behavior of, 441 Copper bearing bar steel grades, 443 Copper bearing forging steels, microalloyed, 440446 Copper-induced surface hot shortness (SHS), 442443 Corrosion-resistant coatings, 24 Corrosion-resistant vehicle bodies, 22 Cottrell atmosphere, 262265, 274, 277, 279 458 Cottrell locking, 100 Cottrell-Bilby model, 261262 CP steel sheet, cooling schedule in production of, 223f Crash avoidance, 10 Crash worthiness, 10, 247 regulations, 1011, 10f Critical safety structure applications, 1922 CrMnSiB DP steels, 173, 174f Cross-die test geometry, 75f Crystallographic texture, 114, 117118 Cullity method, 299300 Cutting clearance, 72f D Deep drawable steels, 113 aluminum killed steels See Aluminum killed (AK) steels bake hardening (BH) steel, 138140 bake hardenable aluminum killed steel, 139140 bake hardenable interstitial free steel, 140 classification of steels based on drawing capacity, 115 grades of, 115116 interstitial free (IF) steels See Interstitial free (IF) steels interstitial free high strength (IFHS) steels See Interstitial free high strength (IFHS) steels measure of, 113115 Deep drawing, 7375, 113, 114f Deep Drawing Ratio (DDR), 61 Deformation parameters, 159 Deformation twinning, 317318, 331332, 339 Deformation-induced transformation, models for of austenite to martensite transformation, 234237 Angel/Ludwigson and Berger, model developed by, 234235 Matsumura et al., model developed by, 235 Mukherjee et al., model developed by, 237 Olson and Cohen, model developed by, 235 Index Sherif et al., model developed by, 237 Shin et al., model developed by, 236237 Sugimoto et al., model developed by, 235236 Dent-resistant steels, 282 Department of Energy (DOE), 36 Destructive tests, 33 Diagonal direction (DD), 5253 Diffuse necking, 5657 Diffusion-controlled solid state phase transformations, 96 Diffusionless transformation of austenite, 104107 Dilatometry, 108 Direct quenching microalloyed forging grade, 438439 Direct water quenched (DWQ) condition, 438 Dislocation mediated twin nucleating process, 335336 Dislocations, 149t Displacive transformations, 417 Docol 2000 Bor, 395396 Double decker furnaces, 388389 DP ferrite-martensite steels, 182 DP600, 87 DP1000 grade, 30 Dual-phase (DP) steels, 46, 2022, 4748, 169, 218f, 219, 223f, 272273, 289, 398 application of, in modern cars, 208 effect of structure on mechanical properties of, 169186 ductility parameters, 180181 existing models of strength of heterogeneous materials, 170172 factors affecting strength characteristics, 172175 fatigue, 185 fracture behavior, 184186 hydrogen embrittlement, 185186 quench and strain aging, 182183 strain hardening, 175180 tempering, 183184 toughness, 184185 effects of chemical composition on, 198208 mechanical properties, 202207 Index phase transformations during annealing in two-phase region, 198201 strain aging and tempering behavior, 207208 microstructure of, 172f obtaining of, by cooling of deformed austenite, 197 obtaining of, by transformations of austenite, 186196 annealing temperature, effect of, 189191 austempering cycle, 194196 cooling rate, effect of, 191194 pseudo-binary Fe(Me)-C diagram, 187f tensile strength of, 173, 183 Ducker Analysis, 89 Ductile ferrite, 2021 Dynamic recrystallization kinetics, 158159 Dynamic strain aging (DSA), 362366 Dynamical Hall-Petch effect, 347348, 347f E Edge cracking, 373 Edge fracture, in hole expansion, 372373 Electrogalvanizing process, 23 Electron backscatter diffraction (EBSD), 305 Electron probe micro-analysis, 362f Energy Independence and Security Act, 11 Engine and transmission components, 12 Engineering stress-strain curves evolution, 292f Environmental Protection Agency (EPA), tailpipe emissions, 11 “Equilibrium amount of austenite”, 187 Equilibrium binary Fe-Mn phase diagram, 322f Eutectic reaction, 9798 Eutectoid reaction, 97 Extended X-ray absorption fluorescence spectroscopy (EXAFS), 441 F Face-centered cubic (fcc) unit cell, 9899 Fatigue strength, 247248 Fe P06, 115 Federal Clean Air Act, Federal Motor Vehicle Safety Standards and Regulations, 10 459 Federal Register, 10 Fe-Mn-C alloy system, 322, 322f Ferrite, 99104, 170, 179, 274275 unit cell crystallographic structure of, 99f Ferrite contraction, 174 Ferrite grains, 179 size, 153f Ferrite nucleation, 228229 Ferrite recrystallization, 206207 Ferrite transformation, 155156, 162, 230231 Ferritebainite mixture, 174, 197 Ferritecarbide interfaces, 189190 Ferritemartensite structure, 196197, 208 Ferritepearlite matrix, 414 Ferritepearlite microstructure, 189 FeTiP precipitation, 130 Fiber cost and panel processing, 16 Finish rolling temperature (FRT), 120, 124, 131 Flanging, 7881 Focused ion beam (FIB) liftouts, 305 Ford Motor Company, 14 Forging grade steels for automotive, 413 automotive forging, steels for, 447448 microalloyed forging steels, evolution of, 436446 low carbon microalloyed forging steels (without copper), 437440 microalloyed copper bearing forging steels, 440446 microalloying in medium carbon steel forgings, 436437 physical metallurgy relevant to hot forging, 417436 phase transformations associated with forging, 417420 precipitates, solute atoms and grains, 425430 stability of precipitates, 420425 strengthening mechanisms operative in microalloyed forging steels, 430436 Formability aspects of steels, 8290 advanced high strength steels, 8890 high strength steels, 8688 mild steels and IF steels, 8386 460 Formability of auto components, 33, 47 advanced high strength steels, 8890 advanced process analysis, 4850 basic concepts of, 48 forming processes, 4950 high strength steels, 8688 material classes, 50 advanced process analysis, 6370 basic concepts, 5063 forming processes, 7081 mild steels and IF steels, 8386 Forming Limit Curve (FLC), 4849, 5758, 67 Forming limit diagram (FLD), 3133, 32f, 58 Forming process, 3133 4150 steel austenite grains of, 103f needle- or plate-shaped crystals of lower bainite in, 104f Fracture, 372373 in hole expansion, 373 of twinning-induced plasticity steel, 372373 Free Form grade, 438 Fuel economy, steel’s contribution to, through mass reduction, 2528 NHTSA Volpe model, 2728 3-G grade, gauge, and geometry optimization, 27 2-G grade and gauge optimization, 2526 vehicle energy losses and contribution to, 1216 Fujita-Mori-Liu model, 334 Future steel technology, 3537 FutureSteelVehicle (FSV), 2728 G Galvannealing (GA), 23, 227, 229, 401 Gas metal arc welding (GMAW), 34 Gas shocks, Generalized planar fault energy (GPFE) curves, 339340 Generalized stacking fault energy (GSFE), 324326 Geometrically necessary inhomogeneous dislocations (GNDs), 274 Gibbs free energy, 323324 Index Gladman analysis, 427429 Global formability, 308309 Glossy painted surfaces, 22 Grain boundary nucleation theory, 161 Grain coarsening temperature, 150 Grain growth, 124125, 130, 134136, 156157, 160, 369371, 428 abnormal grain growth (AGG), 427428 normal grain growth (NGG), 427428 Grain refinement, 147148, 149t, 158, 183, 206207 Grain size refinement, 341, 430 and precipitation, 431432 Graphite, 9697 Greenhouse gas (GHG), 26 emissions, 11, 38f, 39, 4142, 44 life cycle for, 40t, 41t, 42t Guttierez “composite effect”, 347348, 347f H HallPetch analysis, 176f HallPetch coefficient, 175, 342343 HallPetch effect, 317318, 347348, 347f HallPetch equation, 148149, 162163, 342, 343t, 420, 431432 Hardening, 5355 strain rate hardening, 6365 Hardening model, 6870 Hardness measurements, 108 Harper’s model, 261262 H-delayed fracture, 373377 Heat treating and forming process, 14 Heating and cooling, 9596, 108, 420425 High Mn TWIP steel alloy design, principle of, 320326 High Mn TWIP steel and medium Mn steel, 317 aluminium, 328329 carbon, 326327 chromium, 330 copper, nickel, 329 fracture, 372373 fracture, in hole expansion, 373 hydrogen-related delayed fracture, 373377 industrial production, 360362 liquid metal-induced embrittlement, 378379 manganese, 327328 Index mechanical properties of TWIP steel, 330350 critical stress for twinning, 335339 elastic properties, 330331 forming properties, 350351 grain size strengthening in TWIP steel, 342343 high strain rate behavior of TWIP steel, 351352 medium Mn TRIP and TWIP TRIP steel, 352360 micro-alloyed TWIP steel, 344345 principles of medium Mn TRIP and TWIP TRIP steel alloy design, 352360 solid solution hardening, 340341 strain hardening control in medium Mn TWIP TRIP steels, 357360 strain hardening in TWIP steel, 345350 twinning kinetics and twinning saturation, 339340 twinning mechanisms, 331335 nitrogen, 329 recovery annealing, 371372 recrystallization texture, 369371 rolling texture, 366368 silicon, 329 static and dynamic strain aging, 362366 High resolution transmission electron microscopy (HRTEM), 441 High strength IF (IFHS) steel, 128 High strength low alloy (HSLA) steels, 4, 7, 2021, 4748, 145, 146t applications of, 56 history and definition, 145148 hot and cold rolled HSLA steels, in transportation industry, 153154 mechanical properties, 153154 HSLA350, 87 HSLA460, 87 structureproperty relationships, 148149 thermomechanical processing, fundamental metallurgical principles of, 150152 transformation behavior, 155165 hot deformation model, 157160 prediction of mechanical properties, 162164 461 predictive material modeling, current state of, 164 predictive models, application of, 164165 slab reheating, 156157 transformation model, 160162 High strength steel (HSS), 56, 8, 47, 8688 development, 23 products, High-carbon steels, 95, 104107 Higher-strength hot forming steel, 395 Highway Safety Act, 2, 16 Hill model, 6162, 84 H-induced embrittlement, 376 Historic events impacting steel application in vehicle design, 18 Hole edge deformation, 373 Hole expansion capacity (HEC), 7981, 79f Hole expansion ratio (HER), 245246, 246f, 309312, 309f, 312f Hole expansion test, 374f Honda, 6, 30 Honda Civic, Hot and cold rolled HSLA steels, in transportation industry, 153154 mechanical properties, 153154 Hot deformation model, 157160 recovery, 157158 recrystallization, 158160 Hot dip galvanized (GI) steels, 401 Hot forging, 413414 physical metallurgy relevant to, 417436 phase transformations associated with forging, 417420 precipitates, solute atoms and grains, 425430 stability of precipitates, 420425 strengthening mechanisms operative in microalloyed forging steels, 430436 of steel, 413 Hot formed steels, 387 Hot forming, defined, 387 Hot forming steels, 393398 blank coatings, 398402 AlSi coating, 399400 varnish coatings, 402 Zn based coatings, 400401 462 Hot forming steels (Continued) brief history, 390391 coatings after, 401f conventional AHSS, 397 die making strategies for, 390f direct process, 387 energy absorbing, 396 indirect process, 387 intrusion resistant, 393396 medium-Mn steels, 397 physical metallurgy, 392393 stainless steels, 397 typical automotive applications, 402405 tailor hardened parts, 404405 tailor rolled parts, 404 tailor welded parts, 403404 typical hot stamping line, 388390 Hot plate heating, 388389 Hot rolling, 156, 158, 197f, 220 Hot rolling route, 221 complex phase (CP) steels, 222223 TRIP aided steels, 221 Hot stamping, 22, 35, 389390, 392393 Hot-dip galvanizing, 23, 294295 Hot-rolled HSLA sheet steels, 145, 147 HPF1470, 393 HPF2000, 395396 HSLA grade steel, doubly folded, 77f Hydraulic press with accumulator drive, 389 with flywheel, 390 multi-cylinder, 389 Hydroforming, 31 Hydrogen-charging test, 373375 Hydrogen-related delayed fracture, 372377 I Immobilization, 64 Inclusion shape control, 147148 Inductive heating, 388389 Innovative door ring concept, 25f Integrated Computational Materials Engineering (ICME), 36 Intercritical annealing (IA), 169, 186187, 219220 Interstitial free (IF) steels, 47, 116, 127138 chemical composition, importance of, 128130 precipitation in IF steels, 133134 Index processing parameters, importance of, 130138 role of precipitates in, 132133 Interstitial free high strength (IFHS) steels, 127138 chemical composition, importance of, 128130 precipitation in, 134138 processing parameters, importance of, 130138 Intrusion resistant hot forming steels, 393396 Iron carbide, 9697, 115116, 265266 Iron-carbon phase diagram, 9698, 97f Isothermal austenitization curves, 187 kinetics of, 188f Isothermal bainitic transformation (IBT) treatment, 219220 Isothermal hardening, 68, 68f Isothermal holding (IH), 189, 219220, 225, 291, 310312 Isothermal transformation (IT), 108, 109f, 161, 290 J JaoulCrussard model, 176 Java-based Material Properties (JMATPRO), 418419 JohnsonMehlAvramiKolmogorov (JMAK) model, 161, 230 Jominy End Quench curves, 108110, 109f K Killed steel, 23 Kirchhoff assumption, 76 Koistinen-Marburger equation, 292293 Krishtal-Gordon-An model, 378379 L Labeled end-quench test, 109110 Lagrangian formulation, 165 Lankford parameter, 113116 Lankfords coefficient, 52 Laser cutting, 390 Laser processes, 34 Laser welded blanks, 26, 44 Laser welding, 34 Lath martensite, 106, 107f, 219 Index Lattice friction stress, 148149, 340342 Life cycle assessment (LCA), 3943 Life cycle emissions, 26, 41t Lightweighting, 1213, 28, 39 Liquid metal embrittlement (LME), 400 Liquid metal-induced embrittlement (LMIE), 372373, 378379 Local formability, 308309 Local necking analysis, 56, 84 Longitudinal cracks, 377 Low carbon microalloyed forging steels (without copper), 437440 Low carbon-aluminum killed steel, 119f Low-alloyed dual-phase steels, 169 Low-carbon steels, 95, 106 Luăders lines, 23, 67 M Magnesium, 15, 25 Magnesium alloys, 13, 387 Magnesium Vision 2020, 15 Mahajan-Chin model, 332334 Mahajan-Chin stacking fault process, 335336 Manganese, 9596, 122f, 129130, 198, 200, 204f, 225, 327328, 392393 Manganese alloying, 296298 Manganese sulfide inclusions, 9596 Manufacturing concerns, 3135 forming, 3133 painting, 3435 welding/joining, 3334 Martensite, 2021, 104107, 170171, 274275 Martensite crystal, 105f, 106, 107f Martensite finish temperature (Mf), 405 Martensite hardness, 171, 298299 Martensite transformation, 231232, 233f Martensitic sheet products, application of, 56 Martensitic transformation, 231232, 244, 398 Mass balance calculation, 299300, 308 Mass reduction, 2528 Material classes, formability aspects of, 50 advanced process analysis, 6370 forming limit curves, 67 hardening model, 6870 strain rate hardening, 6365 temperature changes, 68 463 yield locus, 6566 basic concepts, 5063 forming limit curve, 5758 hardening, 5355 limits of forming, 5657 strain measures, 5052 stress measures, 53 yield locus, 5863 forming processes, 7081 bending, 7578 cutting, 71 deep drawing, 7375 flanging, 7881 roll forming, 81 stretching, 7273 Matsumura et al., model developed by, 235 MBW1500, 393 Mechanical prediction, 156 Mechanical twinning, 319 Medium carbon steel forgings, microalloying in, 436437 Medium manganese steels, 296 Medium Mn multi-phase steels, 318319 Medium-carbon steels, 95, 102104 Medium-Mn steels, 397398 Metal/tungsten inert gas (MIG/TIG), 34 Metallography, 108 METASAFE steels, 437, 437t Micro band induced plasticity (MBIP) steel, 317 Microalloyed (MA) grades, 436 Microalloyed (MA) steels, 145 forgings, 430 Microalloyed copper bearing forging steels, 440446 Microalloyed forging steels low carbon, 437440 strengthening mechanisms operative in, 430436 Microalloyed HSLA steels, 148 Microalloyed steels, 86 Microalloying constituents, 420425, 433436 Microalloying elements, 147148 Microalloying in medium carbon steel forgings, 436437 Micromill, benefits of, 1415 Microstructural uniformity, 151152 Microstructure, steel, 100101 produced by diffusion, 101104 464 MicrotuffR, 438439 composition and strength toughness of, 439t Mid-size sedan, energy losses in, 13f Mild low carbon steels, 47 Mild steels and IF steels, 8386 Miura-Takamura-Narita nucleation mechanism, 334 Mn enrichment for stabilizing austenite, 221, 222f Mn-B alloyed steels, 387 MoCMnAl steel, 301304 MoCMnSi steel, 301304 Modern hot strip mills, 197 Molybdenum, 9596, 200202, 205, 208, 229 Molybdenum additions, 301304 Monocoque, 45 Monte Carlo algorithm, 281282 Monte Carlo models, 164 Monte Carlo simulations, 4243, 326 of life cycle emissions, 43f Moăssbauer spectroscopy (MS), 299300, 301f, 306308, 326 Mukherjee et al., model developed by, 237 Multi-chamber furnaces, 388389 Multi-cylinder hydraulic press, 389 Multi-phase steels, 205, 217 Multi-phase steels, bake hardening of, 272281, 281f bainitic steels, 279 DP and TRIP steels, 272279 martensitic steels, 279281 N Nano-secondary ion mass spectroscopy (SIMS), 304305, 305f National Highway and Traffic Safety Administration (NHTSA), 2, 1011 fuel economy regulation, 11, 12f Volpe model, 2728, 28f National Steel Corporation, 56, 145 Nb-stabilized steels, 266267 Near infrared heating, 388389 Necking, 53, 5657, 8384, 362363 “New domestic” manufacturers, New United Motor Manufacturing Inc (NUMMI), NHTSA Volpe model, 2728, 28f Index Nickel, 9596, 442443 Niobium, 9596, 132133, 147148, 202, 208, 227228, 438 Niobium microalloying, 290291, 310312 Nippon Steel Corporation (NSC), 217 Nissan, 30 Nitrogen, 23, 128, 264265, 329 Non-equilibrium phase transformation diagram, for Fe-Mn binary alloys, 322f Non-recrystallization temperature, 151152 Normal and abnormal grain growth, 427428 Normal anisotropy, 57, 87, 113114, 373 Normal grain growth (NGG), 427428 North American steelmakers, O Oil crisis, in 1973, 145 Olson and Cohen, model developed by, 235 One-piece hot stamped door ring, 31f One-step Q&P, 292293, 307308 Optimization of mechanical properties, 155156 Ostwald ripening, 157, 427428 Over-aging furnace, 194195 Over-aging temperature, 122, 125127 P Painted surface appearance, 24 Painting, 3435 Panel forming process, 24 Partitioning temperature, 301304, 405 Partitioning time, 295297, 299304, 405 Partitioning treatment, aim of, 292293, 304 Peach-Kohler equation, 332334 Pearlite, 101104, 417, 433436 Peritectic reaction, 9798 Phase transformations, 96, 98, 196f, 418f, 420 associated with forging, 417420 during continuous annealing, 231 effect of steel composition on, 198201 on Run-Out-Table (ROT), 230231 strain-induced, 319 Phosphorous residual, 9596 Phosphorus, 129130, 179, 227 Phs-ultraform, 393 Physical metallurgy of steels, 95 Index austenite, 9899 diffusionless transformation of austenite, 104107 ferrite and cementite, 99100 iron-carbon phase diagram, 9698 steel microstructure, 100101 produced by diffusion, 101104 transformation diagrams and Jominy End Quench curves, 108110 Pick-up truck, 26 Pillar Body Lock Inner, 154 Plain carbon steels, 147148 Planar anisotropy, 48, 113114 Plastic deformation, 5152, 148149, 157, 232233, 236, 331 Plastic incompatibility, 178 Plastic strain ratio, 113 Plasticity modeling, 86 Plasticity-enhancing mechanisms, 317, 319 Plastic-skinned Pontiac Fiero, 45 Polygonal ferrite, 221f, 222 POSCO, 395396 Post-crash standards, 10 Post-World War II economic expansion, Precipitates in interstitial free steels, 132133 stability of, 420425 Precipitates, solute atoms and grains, 425430 Precipitate-time-temperature (PTT) diagrams, 431432 Precipitation, 149t, 207 hardening, 64, 147148, 430 in IF steels, 133134 in IFHS steels, 134138 kinetics, 155156 process, 141 Predictive material modeling, 155156 application of, 164165 current state of, 164 Press formability, 245247 Prehaărten, 390391 Proeutectoid ferrite, 102, 102f Pseudo-binary Fe(Me)-C diagram, 187f, 355f Q Quenching and Partitioning (Q&P) steels, 196, 292294, 405 carbon alloying, 298300 465 competing reactions during partitioning, 304308 local formability of, 308312 manganese alloying, 296298 molybdenum additions, 301304 substitution of silicon by aluminium, 294295 “Quenching and Partitioning” route, 222 Quenching and tempering (Q&T), 307308, 308f Quenching temperature (QT), 292293 R Reconstructive transformations, 417 Recovery annealing, 371372 Recrystallization, 118, 158160 of ferrite, 190191 process, 119 texture, 369371 Reduction of area (RA) for DP steels, 181 Regression analysis, 200 Regulatory pressure, Residual compressive stresses, 95 Retained austenite, 3536, 177, 179180, 184, 219, 227229, 242, 247, 291, 298f deformation-induced transformation of, 231239 factors affecting the stability of, 238239 “Rimmed” steels, 23 Roll forming, 31, 35, 81, 82f Roller hearth furnaces, 388389 Roll-formed parts, Rolling direction (RD), 5253 Rolling texture, 366368 Run-Out-Table (ROT), phase transformation on, 230231 r-value, 5253, 58, 6162, 80 S SAAB, 208, 209f, 391 Safety cell, 21 Safety regulations, 911 Scheil’s additivity theory, 230 Second generation AHSS (2nd Gen AHSS), 3536 2nd generation Volvo XC90, 403 Secondary dendrite arm spacing (SDAS), 430 466 Servo mechanical presses, 390 Shear band induced plasticity (SBIP) steel, 317, 319 Shearing process, 71f Sheet steel grades, 20f Sherif et al., model developed by, 237 Shin et al., model developed by, 236237 Short range ordering (SRO), 363366 Silicon, 9596, 179, 200, 204, 208, 225226, 329, 442443 substitution of, by aluminium, 294295 S-in Motion, 2627 Slab deformation process, 157 Slab reheating, 156157 Slab reheating temperature (SRT), 116, 120, 124, 131 Small angle neutron scattering (SANS), 441 Small angle X-ray scattering (SAXS), 441 Snoek process, 260261 Society of automotive engineers (SAE), 23 Solid solution, 149t Solid solution hardening effect, 64, 420 Solidification, 96 Solubility product, 420423, 422f Solute drag effect, 156157, 425427 Sport utility vehicles (SUVs), Stacking fault energy (SFE), 317318, 322, 326, 359360, 363366 Stainless steels, 397 “Stair-rod cross slip” mechanisms, 333f, 334 Stamping process design, 3133 Static and dynamic strain aging, 362366 Static recrystallization kinetics, 159 Static strain aging (SSA), 138, 362 Steel grade changes, comparison of, 8f Steel grade development, 35 Steel Market Development Institute (SMDI), 39 Steel strengthening mechanisms, 149, 149t Steel-making process, 130 Stoloff-Johnson-Westwood-Kamdar model, 378379 Strain aging, 23, 67, 100, 207, 259, 261262 Strain hardening, 8687, 301304, 345350, 346f, 363366 of dual-phase steels, 175180, 202 in TWIP steel, 345350 Strain measures, 5052 Index Strain rate hardening, 6365 Strain rate sensitivity (SRS), 49, 6364, 67f, 73, 82, 363 Strain-induced phase transformations, 319 Strain-induced transformation, 232233, 320322 Stress assisted transformation, 232233 Stress measures, 53 Stressstrain behavior, 2021 Stressstrain curve, 2021, 21f, 86f, 176, 273f, 277, 290291, 298299, 301304, 329, 354 Stretch flangeability, 79, 88, 245247 Stretch-flanging, 362363, 373 Stretching process, 7273, 74f deformations, 73f schematically, 72f Stretching ratio (STR), 62 Structural adhesives, 34 Structural design, 2122 Structureproperty relationships, 148149, 162163 Substantial austenite retention, 289 Substantial deformation, 151152 Sugimoto et al., model developed by, 235236 Sulfur, 124, 129, 136f Superbainite, 289 Supercell method, 324325, 325f Super-ultra-low carbon (SULC) steels, 259 Surface decarburization, 398 Surface hot shortness (SHS), 442443 Sustainability, 3738 T Tailor rolled blanks (TRB), 404 Tailor welded blank (TWB), 24, 25f, 403404 Tailored blanks, 24 Temperature of non-recrystallization, 151152 Tensile ductility, 308309 Tensile testing, 33 Texture evolution modeling, 86 Texture formation, 130 THERMOCALC computation, 357f Thermodynamic estimations, 326 Thermodynamic parameter, 420423 Thermodynamic stability, 420423 Index Thermomechanical processing (TMP), 36, 145, 151, 197, 228, 265266, 273274, 416 fundamental metallurgical principles of, 150152 Third generation of AHSS (3rd Gen AHSS), 3537 Three-dimensional atom probe tomography, 355, 356f 3-G grade, gauge, and geometry optimization, 27 3-G methodology, 27 Ti-IFHS steel, 136138, 136f stability versus precipitation temperature of, 138f Time-temperature-transformation (TTT) diagram, 161, 224f, 419f, 431432, 434f Tire rolling resistance, 12 Ti-stabilized interstitials-free (Ti-IF) ferritic steel, 319320 Ti-stabilized steels, 266267 Titanium, 9596, 147148, 202, 228 Titanium stabilized interstitial-free steel, 101f equiaxed ferrite grains in, 101f TomotaTamura model, 171 Total elongation (TE), 181 ductility measurement by, 244 Toyota Corolla, Toyota Venza, 26 TPCP (Thermo-mechanical Precipitation Control Process), 443, 445, 446t, 447f Transformation diagrams and Jominy End Quench curves, 108110 Transformation induced plasticity-aided steel, 289, 398 Transformation modeling, 156, 160162 Transformation rate, 161 Transformation strengthening, 430 and thermo-mechanical processing, 433436 Transformation temperature, 163, 228 Transformed fraction, 161 Transition carbides, 306307 Transmission electron microscopy, 103 Transportation industry, 12 Transverse direction (TD), 5253 467 TRIP aided and complex phase steels, 217 See also Complex phase (CP) steels alloy design, 224229 aluminum, 226227 carbon, 224225 chromium, 229 manganese, 225 molybdenum, 229 niobium, 227228 phosphorus, 227 silicon, 225226 titanium, 228 vanadium, 228229 crashworthiness, 247 fatigue strength, 247248 mechanical properties, 239245 effects of strain rate, 244245 effects of temperature, 243244 microstructure modeling, 229231 empirical models, 231 phase transformation during continuous annealing, 231 phase transformation on ROT, 230231 models for deformation-induced transformation of austenite to martensite, 234237 Angel/Ludwigson and Berger, model developed by, 234235 Matsumura et al., model developed by, 235 Mukherjee et al., model developed by, 237 Olson and Cohen, model developed by, 235 Sherif et al., model developed by, 237 Shin et al., model developed by, 236237 Sugimoto et al., model developed by, 235236 press formability, 245247 retained austenite, additional factors affecting the stability of, 238239 TRIP aided plasticity mechanism in low alloy TRIP aided steel, 241f TRIP aided steel, 219222 with bainitic ferrite matrix (TBF), 236f cold rolling (CR) route, 220 hot rolling (HR) route, 220221 468 TRIP aided steel (Continued) stretch flangeability of, 246 TTT behavior in, 224f two-step heat treatment for, 219f TRIP effect, 217, 245, 274, 318319, 318f, 354, 357359 TRIP steels, 272274, 277, 294295 TRIP-aided bainitic ferrite (TBF), 290, 405 True strain, 5051 Twin thickening mechanism, 332334 Twinning stress, 335338, 345347 Twinning-induced plasticity, 317 TWIP effect, 318319, 318f, 332334, 354, 357360 TWIP steel, mechanical properties of, 330350 critical stress for twinning, 335339 elastic properties, 330331 forming properties, 350351 grain size strengthening, 342343 high strain rate behavior, 351352 medium Mn TRIP and TWIP TRIP steel, 352360 micro-alloyed TWIP steel, 344345 principles of medium Mn TRIP and TWIP TRIP steel alloy design, 352360 solute solution hardening, 340341 strain hardening, 345350 strain hardening control in medium Mn TWIP TRIP steels, 357360 twinning kinetics and twinning saturation, 339340 twinning mechanisms, 331335 TWIP steel, twinning shear stress value for, 335t 2-G grade and gauge optimization, 2526 2015 Acura TLX, 30, 31f 2015 Ford Edge, 30, 30f, 170f Two-step heat treatment, microstructural changes during, 220f Typical hot stamping time-temperature profile, 389f U Ultimate tensile strength (UTS), 54, 128, 177, 296297, 309310, 319320 Ultra-fine grained (UFG) microstructures, 356357 Ultrahigh strength steels, 4, 219 Index Ultra-low carbon (ULC) steels, 259 Uniform elongation, 181 ductility measurement by, 244 United States Automotive Materials Partnership LLC (USAMP), 15 United States Center for Automotive Research (USCAR), 36 University of California Santa Barbara Automotive Materials GHG Comparison Model V4 (UCSB Model), 3942 USIBOR 1500, 393 V Vacuum degassing technique, 128, 130 Vacuum degassing technology, 127128 Vanadium, 9596, 147148, 202, 228229 Varnish coatings, 402 VDA238 test equipment, 76f, 7778 Vehicle curb weight, 3f Vehicle downsizing, Vehicle energy losses and contribution to fuel economy, 1216 aluminum, 1415 carbon fiber reinforced polymers, 1516 magnesium, 15 Vehicle manufacturing, 31 Vehicle mass, 7, 12, 30, 44 Vehicle mass breakdown, 13, 13f Vehicle migration, Vehicle noise, vibration, and harshness (NVH) performance, 24 Venables pole mechanism, 335336 Vickers Hardness (HV) values, 394395 V-microalloyed HSLA steel, 147148 Volkswagen Beetle, Volpe model, 2728 W Warm forging, 413414 Warm forming, 14 Water quenching (WQ), 307308, 308f Weldability, 3334 Welding, 3334 Work hardening, 53, 64, 88, 88f, 89f, 178, 204, 244245, 272273 WorldAutoSteel, 27, 39 Index X X-ray absorption near edge spectroscopy (XANES), 441 X-ray diffraction analysis, 299300 Y Yield locus, 48, 5863, 60f, 61f, 62f, 6566 Yield point elongation (YPE), 86, 174, 362, 363f Yield strength, 4, 2024, 121, 147, 162163, 259, 371 Yield stress, 53, 5556, 5859, 6465, 342 Yoshida-Uemori model, 8990 YS/TS (yield strength/tensile strength) ratio, 170, 174, 178 469 Z Zener pinning mechanism, 156157, 425427 ZenerHolloman parameter, 158159 Zinc coated automotive steels, 34 Zinc coatings, 23, 34 Zinc-coated steels, ZinQuench system, 196 Zirconium, 202 Zn based coatings, 400401 Zn coated blanks, 400 Zn liquid metal embrittlement (Zn-LMIE), 378379 ZnNi coating, 401402