Francisco C. Robles-Hernandez Jose Martin Herrera Ramírez Robert Mackay. Al-Si Alloys Automotive, Aeronautical, and Aerospace Applications

Francisco C. Robles-Hernandez Jose Martin Herrera Ramírez Robert Mackay Al-Si Alloys Automotive, Aeronautical, and Aerospace Applications

Francisco C. Robles-Hernandez Jose Martin Herrera Ramírez Robert Mackay Al-Si Alloys Automotive, Aeronautical, and Aerospace Applications

Francisco C. Robles-Hernandez College of Technology University of Houston Houston, Texas, USA Jose Martin Herrera Ramírez Centro de Investigación en Materiales Avanzados Chihuahua, Mexico Robert Mackay Metallurgical & Heat Treatment Nemak US/Canada Business Unit Windsor, Ontario, Canada ISBN 978-3-319-58379-2 DOI 10.1007/978-3-319-58380-8 ISBN 978-3-319-58380-8 (ebook) Library of Congress Control Number: 2017943091 Springer International Publishing AG 2017 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. The publisher, the authors and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the of publication. Neither the publisher nor the authors or the editors give a warranty, express or implied, with respect to the material contained herein or for any errors or omissions that may have been made. The publisher remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Printed on acid-free paper This Springer imprint is published by Springer Nature The registered company is Springer International Publishing AG The registered company address is: Gewerbestrasse 11, 6330 Cham, Switzerland

Acknowledgments Dr. Francisco C. Robles Hernandez acknowledges and appreciates the outstanding support of the government of Mexico by providing a fellowship through the Consejo Nacional de Ciencia y Technologia (CONACyT) to conduct his PhD studies. Part of the experimental work included in this book was completed during his PhD studies. Dr. Martin Herrera Ramirez and MSc. Armando Tejada Ochoa greatly appreciate the support of Dr. Roberto Martinez-Sanchez and Dr. Ivanovich Estrada-Guel for facilitating the use of the mechanical alloying facilities at CIMAV-Chihuahua as well as their technical guidance for the mechanical alloying experiments. Special thanks to Mrs. Adriana Ramos-Palomino and Mr. Jose Ernesto Ledezma-Sillas for editing some of the images and for designing others. Martin Herrera Ramirez thanks CONACyT for the support during his sabbatical year (grant number 255695). Armando Tejeda Ochoa also thanks CONACyT for his doctoral scholarship (grant number 445419). Dr. Robert Mackay acknowledges the Nemak of Canada Corporation and his staff and coworkers for supporting his objectives in both forensic analysis of casting defects and the pursuit of aluminum alloy and process development for the metal casting industry. Dr. Mackay is also grateful to his former graduate supervisors and his current employer for encouraging him to pursue the extensive publication record he has achieved to, all of which has instilled the confidence to participate in the coauthorship of this textbook. xv

Contents 1 Al-Si Alloys, Minor, Major, and Impurity Elements... 1 1.1 General Overview: Aluminum Silicon Alloys... 1 1.2 Alloy Designations... 3 1.3 ASTM Standards for Testing AL-SI Castings... 3 1.4 Effect of Main Chemical Constituents of AL-SI Hypereutectic Alloys... 4 1.5 Major Alloying Elements... 4 1.5.1 Silicon... 4 1.5.2 Copper... 6 1.5.3 Nickel... 9 1.5.4 Magnesium... 9 1.5.5 Zinc... 10 1.6 Impurity Elements... 10 1.6.1 Iron... 10 1.6.2 Manganese... 11 References... 12 2 Thermal Analysis... 17 2.1 Introduction... 17 2.2 Thermal Analysis Procedure... 19 2.3 Heat Exchange Conditions... 19 2.4 Experimental Results and Thermal Analysis Algorithms... 21 2.5 Applications of the Thermal Analysis Algorithms... 29 2.6 Thermal Analysis, Quench Testing, and Optical Microscopy... 34 2.7 Characterization: Optical and Scanning Electron Microscopy... 36 References... 43 3 Metal Casting Process... 47 3.1 Casting Processes: Overview... 47 3.2 High Pressure Die Casting Process... 49 3.3 Lost Foam Process... 55 3.4 Sand Casting and Precision Sand Casting Process... 59 xvii

xviii Contents 3.5 Aerospace Sand Casting Applications... 60 3.6 Precision Sand for Automotive Applications... 64 3.7 Semi-Permanent Molding Process... 66 3.8 Permanent Mold Process... 72 3.9 Investment Casting Process... 74 3.10 Casting Process Selection... 76 3.11 Heat Treatment Process for Aluminum Castings... 77 References... 79 4 Powder Metallurgy... 81 4.1 Introduction to Mechanical Milling... 81 4.2 Al-Si Alloys... 83 4.3 Powder Production Methods... 84 4.4 Mechanical Alloying... 86 4.5 Consolidation Methods... 91 4.6 Sintering... 95 References... 104 5 Liquid and Semisolid Melt Treatment: Electromagnetic Stirring... 109 5.1 Introduction to Electromagnetic Stirring... 109 5.2 Electromagnetic Stirring (ES) Principle... 110 5.3 Mechanical and Ultrasonic Stirring... 113 5.4 Electromagnetic Stirring and Vibration... 113 5.5 Discussion of Silicon Modification... 122 References... 126 6 Mechanical Properties... 131 6.1 Mechanical Strength and Durability Assessment... 132 6.2 Tensile Testing Properties... 132 6.2.1 Tensile Test Sample Geometries for Casting... 136 6.2.2 Precision Sand with Implemented Chill... 136 6.2.3 Tensile Properties of Casting Sections Where Cylindrical Samples Are Not Possible... 138 6.3 Weibull Statistical Method for Treating Tensile Test Data... 141 6.3.1 Examples of Weibull Statics Used in Aluminum Castings... 142 6.4 Fatigue Durability of Aluminum Castings... 146 6.4.1 Fatigue Staircase Generation for Al-Si Castings... 151 6.5 Weld Repair of Aluminum Castings... 155 References... 159 7 Applications in the Automotive and Aerospace Industries... 161 7.1 Aluminum Alloys: A Brief History... 161 7.2 Casting Quality Requirements... 163 7.3 Applications of Aluminum Castings in Automotive and Aerospace Industries... 165 7.4 Impact of Aluminum Cost on Casting Processes... 168

Contents xix 7.5 Aerospace... 168 7.6 Automotive... 168 References... 169 8 Principles of Solidification... 171 8.1 Aluminum Alloy Systems... 171 8.2 Alloy Designations... 173 8.3 Solidification Sequence of Al-Si Alloys... 175 8.4 Primary-Phase Evolution: α-al Dendritic Structure... 176 8.4.1 Effect of Silicon Concentrations... 180 8.4.2 Effect of Iron Concentrations... 182 8.4.3 Effect of Copper Concentrations... 185 8.4.4 Effect of Magnesium Concentration... 186 8.4.5 Si Eutectic Modifiers: Strontium, Antimony, and Sodium... 187 8.4.6 Grain Refinement... 189 8.5 Mechanism for Pore Development... 189 8.6 Hydrogen Concentrations: Measurement and Established Thresholds... 191 8.7 Methods of Hydrogen Absorption... 193 8.8 Kinetics for Oxide Generation... 195 8.9 Titanium Boride (TiB 2 ) Inclusions... 196 8.10 Strontium-Based Inclusions... 197 8.11 Reduced Pressure Test Methodology... 197 8.12 Methods for Degassing... 203 References... 206 9 Grain Refinement... 209 9.1 Introduction to Grain Refinement... 209 9.2 Chemical Grain Refinement... 210 9.2.1 Principles and Grain Growth Restriction Factor... 210 9.2.2 Grain Refinement of Aluminum-Rich Phases... 211 9.3 Silicon in Liquid and Semisolid States... 213 9.3.1 Structure in the Liquid State... 213 9.3.2 Al-Si Hypereutectic Alloys... 213 9.3.3 Primary Si Growth... 218 9.4 Silicon Modification Methods... 220 9.4.1 Chemical Modification of Si Rich Phases... 220 9.4.2 Thermal Modification... 223 9.4.3 Mechanical Modification... 225 References... 226 Index... 233

DocuSign Envelope ID: 9765AC71-971F-4BB8-BC81-30B8E7E223BC February 7, 2016 Publishing Agreement This amendment modifies the Publishing Agreement d January 14, 2016 between Francisco Robles-Hernandez, UNIV OF HOUSTON, 4800 CALHOUN, HOUSTON, TX 77204, USA Dr. Jose Martin Herrera Ramírez, Centro de Investigación en Materiales Avanzados, Miguel de Cervantes 120, Complejo Industrial Chihuahua, Chihuahua, Chih. 31136, Mexico Robert I. Mackay, Metallurgical & Heat Treatment Specialist, Nemak US/Canada Business Unit, 4655 G.N. Booth Drive, Windsor Ontario,N9C 4G5 shall be an additional Editor of the Work. (hereinafter called Author) on the one part and Springer International Publishing AG, Gewerbestrasse 11, 6330 Cham, Switzerland (hereinafter called Springer) on the other part, regarding a book entitled Al-Si Alloys - Automotive, Aeronautical, and Aerospace Applications (hereinafter called Work) When Author is more than one person, the expression Author as used in this agreement will apply collectively unless otherwise indicated. 1 Clarification of Role Francisco Robles-Hernandez, Jose Martin Herrera Ramírez, and Robert I Mackay are all Authors of the Work, not Editors as indicated in the previous amendment. All other provisions of the Publishing Agreement of January 14, 2016 remain unchanged The Author(s) Springer International Publishing AG, Cham Dr. Francisco Robles-Hernandez Guido Zosimo Landolfo Editorial Director/Asset Management

DocuSign Envelope ID: 9765AC71-971F-4BB8-BC81-30B8E7E223BC Dr. Jose Martin Herrera Ramírez Physical Sciences & Engineering Representative SIP AG Dr. Robert I. Mackay Order Number: 86777705 GPU/PD/PS: 3/37/495