Foseco Non-Ferrous Foundrymans Handbook

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Foseco Non-FerrousFoundrymans Handbook

Eleventh edition

Revised and edited byJohn R. Brown

OXFORD AUCKLAND BOSTON JOHANNESBURG MELBOURNE NEW DELHI

Butterworth-HeinemannLinacre House, Jordan Hill, Oxford OX2 8DP225 Wildwood Avenue, Woburn, MA 01801-2041A division of Reed Educational and Professional Publishing Ltd

A member of the Reed Elsevier plc group

Ninth edition published by Pergamon Press plc 1986Tenth edition 1994Reprinted 1995, 1996, 1998Eleventh edition 1999

Foseco International Ltd 1994, 1999

All rights reserved. No part of this publicationmay be reproduced in any material form (includingphotocopying or storing in any medium by electronicmeans and whether or not transiently or incidentallyto some other use of this publication) without thewritten permission of the copyright holder except inaccordance with the provisions of the Copyright,Designs and Patents Act 1988 or under the terms of alicence issued by the Copyright Licensing Agency Ltd,90 Tottenham Court Road, London, England W1P 9HE.Applications for the copyright holders written permissionto reproduce any part of this publication should be addressedto the publishers

British Library Cataloguing in Publication DataBrown, John R.

Foseco non-ferrous foundrymans handbook1. Nonferrous metals Founding Handbooks, manuals, etc.I. Title673

ISBN 0 7506 4286 6

Library of Congress Cataloguing in Publication DataFoseco non-ferrous foundrymans handbook/revised and edited by John

R. Brown 11th ed.p. cm.Prev. eds. published under title: Foseco foundrymans handbook.ISBN 0 7506 4286 61. Founding Handbooks, manuals, etc. 2. Nonferrous metals Founding Handbooks, manuals, etc. I. Brown, John R. II. Title:Non-ferrous foundrymans handbook. III. Title: Foseco foundrymanshandbook.TS235.F585 9934984673dc21 CIP

Composition by Genesis Typesetting, Rochester, KentPrinted and bound in Great Britain

Contents

Preface xi

Acknowledgements xii

Chapter 1 Tables and general data 1

SI units and their relation to other units 1SI, metric, non-SI and non-metric conversions 2Conversion table of stress values 5Areas and volumes of circles, spheres, cylinders etc. 6The physical properties of metals 7Densities of casting alloys 9Approximate bulk densities of common materials 10Patternmakers contraction allowances 11Volume shrinkage of principal casting alloys 13Comparison of sieve sizes 14Calculation of average grain size 15Calculation of AFS grain fineness number 16Recommended standard colours for patterns 17Dust control in foundries 18Buoyancy forces on cores 18Core print support 19Opening forces on moulds 19Dimensional tolerances and consistency achieved in castings 21

Chapter 2 Aluminium casting alloys 23

Introduction 23Casting alloys 25Casting processes 39The effect of alloying elements 39Heat treatment of aluminium alloys 42

Chapter 3 Melting aluminium alloys 46

Introduction 46Raw materials 47Melting furnaces 47Corundum growth 54Choice of melting unit 55

vi Contents

Chapter 4 Fluxes 56

Introduction 56Application of COVERAL powder fluxes 56Granular COVERAL fluxes 61

Chapter 5 INSURAL refractory for ladles and metal transport 63

Introduction 63Ladle liners 65

Chapter 6 Treatment of aluminium alloy melts 70

Introduction 70Hydrogen gas pick-up in aluminium melts 70Degassing aluminium alloys 72Grain refinement of aluminium alloys 77Modification of aluminium alloys 79Sodium modification 81Strontium modification 82Permanent modification 83Melting procedures for commonly used aluminium alloys 83Sand, gravity die and low pressure diecasting 83Medium silicon alloys, 47% Si 84Eutectic silicon alloys, 12% Si 84Treatment of hypereutectic AlSi alloys (over 16% Si) 85Melting and treatment of aluminiummagnesium alloys (410% Mg) 86Special requirements for gravity diecasting 87Treatment of alloys for pressure diecasting 87

Chapter 7 Running, gating and feeding aluminium castings 89

Introduction 89Gating without filters 90Gating with filters 93Feeding mechanisms in Al alloy and other non-ferrous castings 94Simulation modelling 98

Chapter 8 Filtration of aluminium alloy castings 99

Introduction 99SIVEX FC filters 100Use of conventional running systems 101Direct pouring of aluminium alloy castings 104KALPUR combined sleeve and SIVEX FC filter for aluminium

castings 105Direct pouring into metal dies 107

Contents vii

Chapter 9 Pressure diecasting of aluminium alloys 108

Introduction 108Die design 109Process control 111Modification of the diecasting process 113Applications of diecasting 114The diecasting foundry 114Die coating 116

Chapter 10 Low pressure and gravity diecasting 118

Low pressure diecasting 118Gravity diecasting 124Die coatings for gravity and low pressure diecasting 127

Chapter 11 Sand casting processes 135

Introduction 135Green sand 136Moulding machines 137Core assembly sand processes 140The Lost Foam process 144

Chapter 12 Sands and sand bonding systems 149

Silica sand 149Properties of silica sand for foundry use 149Typical silica foundry sand properties 151Safe handling of silica sand 152Segregation of sand 153Measurement of sand properties 153Thermal characteristics of silica sand 153Non-silica sands 154Zircon, ZrSiO4 154Chromite, FeCr2O4 156Olivine, Mg2SiO4 156Green sand 156Green sand additives 157The green sand system 160Green sand properties 163Control of green sand systems 164Sand testing 165Control graphs 165Parting agents 166Special moulding materials, LUTRON 166

viii Contents

Chapter 13 Resin bonded sand 167

Chemically bonded sand 167Self-hardening process 167Testing chemically bonded, self-hardening sands 169Mixers 171Sand quality 172Pattern equipment 172Curing temperature 173Design of moulds using self-hardening sand 173Foundry layout 173Sand reclamation 175Typical usage of sand reclamation 178Self-hardening resin binder systems 180Furanes 180Phenolic-isocyanates 182Alkaline phenolic resin, ester hardened 183Triggered hardening systems 185Heat triggered processes 185Gas triggered systems 186Heat triggered processes 187The shell or Croning process 187Hot-box process 189Warm-box process 190Oil sand 191Gas triggered processes 193Phenolic-urethane-amine gassed (cold-box) process 193ECOLOTEC process 195The SO2 process 196SO2-cured epoxy resin 198Ester-cured alkaline phenolic system 198Review of resin core-making processes 199

Chapter 14 Sodium silicate bonded sand 204

Introduction 204Sodium silicate 204CO2 silicate process 205Gassing CO2 cores and moulds 207Improvements to the CO2 silicate process 208The CARSIL range of silicate binders 209SOLOSIL 209Self-setting sodium silicate processes 210Ester silicate process 210Adhesives and sealants 215CORSEAL sealants 215TAK sealant 215

Contents ix

Chapter 15 Magnesium casting 217

Casting alloys 217The melting, treatment and casting of magnesium alloys 218

Chapter 16 Copper and copper alloy castings 225

The main copper alloys and their applications 225Specifications for copper-based alloys 226Colour code for ingots 227Melting copper and copper-based alloys 232Melting and treatment of high conductivity copper 238Melting and treatment of high conductivity copper alloys 242Coppersilver 242Coppercadmium 243Copperchromium 243Commercial copper 243Melting and treatment of brasses, copperzinc alloys 244Melting bronzes and gunmetals 248Melting aluminium bronze 250Melting manganese bronze 250Melting high lead bronze 250Melting coppernickel alloys 251Filtration of copper-based alloys 251

Chapter 17 Feeding systems 252

Introduction 252Natural feeders 252Aided feeders 253Feeding systems 254The calculation of feeder dimensions 257Determination of feeding requirements 262Steel, malleable iron, white irons, light alloys and copper-based

alloy castings 262Grey and ductile irons 266FOSECO feeding systems 268Introduction 268Range of feeder products 269Breaker cores 279The application of feeder sleeves 280Williams Cores 283FERRUX anti-piping compounds for iron and steel castings 284Metal-producing top surface covers 285FEEDOL anti-piping compounds for all non-ferrous alloys 286

x Contents

Aids to the calculation of feeder requirements 286Nomograms 287FEEDERCALC 287Calculating feeder sizes for aluminium alloy castings 288

Index 289

Preface

The last edition of the Handbook was published in 1994 and like all the earliereditions, it aimed to provide a practical reference book for all those involvedin making castings in any of the commonly used alloys by any of the usualmoulding methods. In order to keep the Handbook to a reasonable size, it wasnot possible to deal with all the common casting alloys in detail. Since 1994the technology of casting has continued to develop and has become morespecialised so that it has been decided to publish the 11th edition of theHandbook in three separate volumes:

Non-ferrous dealing with aluminium, copper and magnesium castingalloys

Iron dealing with grey, ductile and special purpose castirons

Steel dealing with carbon, low alloy and high alloy steels

Certain chapters (with slight modifications) are common to all threevolumes: these chapters include tables and general data, sands and sandbonding systems, resin bonded sand, sodium silicate bonded sand andfeeding systems. The remaining chapters have been written specifically foreach volume.

The Handbook refers to many Foseco products. Not all of the products areavailable in every country and in a few cases, product names may vary.Users should always contact their local Foseco company to check whether apart