Cover image for Physical metallurgy of direct chill casting of aluminum alloys
Title:
Physical metallurgy of direct chill casting of aluminum alloys
Personal Author:
Publication Information:
Boca Raton : CRC Press, 2008
Physical Description:
xix, 301 p. : ill. ; 24 cm.
ISBN:
9781420062816

Available:*

Library
Item Barcode
Call Number
Material Type
Item Category 1
Status
Searching...
30000010186056 TN775 E748 2008 Open Access Book Book
Searching...
Searching...
30000003505140 TN775 E748 2008 Open Access Book Book
Searching...

On Order

Summary

Summary

Pulling together information previously scattered throughout numerous research articles into one detailed resource, Physical Metallurgy of Direct Chill Casting of Aluminum Alloys connects the fundamentals of structure formation during solidification with the practically observed structure and defect patterns in billets and ingots. The author examines the formation of a structure, properties, and defects in the as-cast material in tight correlation to the physical phenomena involved in the solidification and the process parameters.

The book draws on the author's advanced research to provide a unique application of physical metallurgy to direct chill (DC) casting technology. He examines structure and defect formation-- including macrosegregation and hot tearing. Each technology-centered chapter provides historical background before reviewing current developments. The author supports his conclusions with computer simulation results that have been correlated with highly progressive experimental data. He presents a logical system of structure and defect formation based on the specific features of the DC casting process. He also demonstrates that the seemingly controversial results reported in literature are, in fact, caused by the different ratio of the same mechanisms.

Compiling recent results and data, the book discusses the fundamentals of solidification together with metallurgical and technological aspects of DC casting. It gives new insight and perspective into DC casting research.


Table of Contents

List of Symbols and Abbreviationsp. xi
Prefacep. xv
Authorp. xix
1 Direct Chill Casting: Development of the Technologyp. 1
Referencesp. 17
2 Solidification of Aluminum Alloysp. 19
2.1 Effect of Cooling Rate and Melt Temperature on Solidification of Aluminum Alloysp. 19
2.2 Microsegregation in Aluminum Alloysp. 28
2.3 Solidification Reactions and Phase Compositionp. 43
2.3.1 Commercial Aluminump. 43
2.3.2 Wrought Alloys with Manganese (3XXX Series)p. 46
2.3.3 Al-Mg-Si Wrought Alloys (6XXX Series)p. 47
2.3.4 Al-Mg-Si-Cu Wrought Alloys (6XXX and 2XXX Series)p. 50
2.3.5 Al-Mg-Mn Wrought Alloys (5XXX Series)p. 51
2.3.6 Al-Cu-Mn (Mg, Si, Ni) Wrought Alloys (2XXX Series)p. 54
2.3.7 Al-Mg-Zn-(Cu) Wrought Alloys (7XXX Series)p. 55
2.3.8 Wrought Alloys Containing Lithiump. 56
2.3.8.1 Al-Cu-Li Commercial Alloysp. 56
2.3.8.2 Al-Li-Mg Commercial Alloysp. 57
2.3.8.3 Al-Li-Cu-Mg Commercial Alloysp. 57
2.4 Effect of Alloy Composition on Structure Formation: Grain Refinementp. 59
2.4.1 Mechanisms of Grain Refinementp. 59
2.4.2 Al-Sc-Zr Phase Diagramp. 68
2.4.3 Al-Ti-B Phase Diagramp. 70
2.4.4 Al-Ti-C Phase Diagramp. 71
Referencesp. 75
3 Solidification Patterns and Structure Formation during Direct Chill Castingp. 79
3.1 Shape and Dimensions of the Billet Sumpp. 79
3.2 Solidification Rate and Cooling Rate during DC Castingp. 91
3.3 Effects of Process Parameters on the Formation of Grain Structurep. 101
3.4 Effect of Process Parameters on the Amount of Nonequilibrium Eutecticsp. 111
3.5 Effect of Process Parameters and Alloy Composition on the Occurrence of Some Casting Defectsp. 115
Referencesp. 122
4 Macrosegregationp. 125
4.1 Mechanisms of Macrosegregationp. 125
4.1.1 Historic Overviewp. 125
4.1.2 Permeabilityp. 132
4.1.3 Convection-Driven Macrosegregationp. 136
4.1.4 Shrinkage-Driven Macrosegregationp. 141
4.1.5 Floating Grains and Macrosegregationp. 145
4.1.6 Deformation-Driven Macrosegregationp. 151
4.2 Effects of Process Parameters on Macrosegregation during DC Castingp. 152
4.2.1 Effect of Casting Speed on Macrosegregation during DC Castingp. 152
4.2.2 Effect of Melt Temperature on Macrosegregation during DC Castingp. 159
4.2.3 Dimensions of the Billet: Scaling Rule of Macrosegregationp. 159
4.2.4 Effect of Forced Convection on Macrosegregation during DC Castingp. 169
4.3 Effect of Composition on Macrosegregation: Macrosegregation in Commercial Aluminum Alloysp. 170
Referencesp. 179
5 Hot Tearingp. 183
5.1 Thermal Contraction during Solidificationp. 185
5.2 Mechanical Properties of Semi-Solid Alloysp. 200
5.2.1 Testing Techniquesp. 200
5.2.2 Strength Properties of Aluminum Alloys in the Semi-Solid Statep. 205
5.2.3 Ductility of Aluminum Alloys in the Semi-Solid Statep. 208
5.3 Mechanisms and Criteria for Hot Tearingp. 216
5.3.1 Historic Overview of Hot Tearing Research and Suggested Mechanismsp. 216
5.3.2 Hot Tearing Criteriap. 225
5.3.2.1 Stress-Based Criteriap. 225
5.3.2.2 Strain-Based Criteriap. 229
5.3.2.3 Strain Rate-Based Criteriap. 231
5.3.2.4 Criteria Based on Other Principlesp. 234
5.3.3 Application of Hot Tearing Criteria to DC Casting of Aluminum Alloysp. 236
5.3.4 Quest for a New Hot Tearing Criterionp. 240
5.4 Effects of Process Parameters on Hot Tearing during DC Castingp. 245
5.4.1 Thermo-Mechanical Behavior of a DC-Cast Billet (Ingot)p. 246
5.4.2 Effects of Composition and Casting Speed on Hot Tearing during DC Castingp. 251
5.4.3 Effect of Melt Temperature on Hot Tearing during DC Castingp. 259
5.4.4 Structural Features Associated with Hot Tearing in DC Castingp. 262
Referencesp. 269
Concluding Remarksp. 275
Subject Indexp. 289