About the Book
This book is a collection of papers presented at the 4th International Symposium on Gamma TiAl Alloys (ISGTA 2014) that was held in conjunction with the 2014 Annual Meeting of The Minerals, Metals & Materials Society. Papers discuss and assess advances in application and implementation experience in current alloys, fundamental
aspects in current gamma alloy materials technology, new processes development and assessment, and emerging new alloys, their potentials and limitations, and breakthroughs.
Papers that originated in the panel discussion of the symposium are intended to help the scientific community realize the limitations of current alloys materials and processes and discuss possible solutions. Six topic areas selected for this purpose included:
Wrought-processed alloys: status, dilemmas and pathways to future
Cast alloys for aero engine applications: status, issues, and barriers to advances
Cast alloys for turbocharger wheels: status and barriers to widespread applications
Emerging new alloys: justification, potentials, status, and future
Novel processes: justification, potential vs. realization issues, and future
Future applications and realistic pathways to them
Table of Contents:
Preface viii Editors x
Alloy Design and Development
Alloy Design Concepts for Wrought High Temperature TiAl Alloys 3
J. Lin, X. Xu, L. Zhang, Y. Liang, Y. Xu, and G. Hao
Physical Metallurgy and Performance of the TNB and y-Md Alloys 9
F. Appel, M. Oehring, and J. Paul
A Quarter Century Journey of Boron as a Grain Refiner in TiAl Alloys 21
D. Hu
Composition Optimization of B-y TiAl Alloys Containing High Niobium 31
L. Zhang, J. Zheng, Y. Hou, X. Ma, X. Xu, and J. Lin
Processing and Fabrication
Impact of ISM Crucible Tilting Process on Mould Filling and Yield of Near-net Shape TiAl Turbine Blades 39
O. Kattlitz, J. Aguilar, and S. Jana
The Effect of Mould Pre-Heat Temperature and Casting Dimensions on the Reaction Between TiAl Alloy and the Zirconia Investment Casting Moulds 45
C. Yuan, X. Cheng, D. Shevchenko, G. Holt, and P. Withey
Experimental Research on the Recycling Potential of Precision Casty-TiAl During Electroslag Remelting 51
M. Bartosinski, C. Lochbichler, J. Reitz, P. Spiess, B. Friedrich, T. Stoyanov, and J. Aguilar
Influence of the Slag Composition on the Fluorine Absorption in y-TiAl during IESR 59
P. Spiess, and B. Friedrich
Response of Melt Treatment on the Solidified Microstructure of Ti-48Al-2Cr-2Nb Alloy 65
G. Yang, H. Kou, J. Yang, J. Wang, J. Li, and H. Fu
Recent Development and Optimization of Forging Process of High Nb-TiAl Alloy 71
X. Xu, J. Lin, L. Zhang, and Y. Liang
Fabrication of TiAl Alloys by Alternative Powder Metallurgical Methods 77
M. A. Largos, I. Agote, J.M. San Juan, and J. Hennicke
Manufacturing and Properties of High Nb-TiAl Sheet Materials 83
Y. F. Liang, Z. Z. Shen, H. Wang, L. Q. Zhang, X. J. Xu, Y. Xu, G. J. Hao, and J. P. Lin
Reaction Behavior during Heating of Multilayered Ti/Al Foils 87
Z. Shen, Y. Liang, L. Zhang, G. Hao, J. He, and J. Lin
High Nb Content TiAl Alloys Specified to Cast Process 93
H. Li, and J. Zhang
Joining and Surface Protection
Electron Beam Joining of y-Titanium Aluminide 99
U. Reisgen, S. Olschok, and A. Backhaus
Mechanical Properties and Microstructure of a TNM Alloy Protected by the Fluorine Effect and Coated with a Thermal Barrier 105
A. Straubel, S. Friedle, M. Schiitze, N. Laska, R. Braun, and C. Leyens
Wear Protection for Turbine Blades Made of Titanium Aluminide Ill
A. Werner, W. Smarsly, and J. Efilinger
Effect of Er Addition on Microstructure and Oxidation Resistance of High Nb Containing TiAl Alloys 117
L. Chai, Z. Gong, F. Zhou, Z. Chen, and Z. Nie
Fundamentals
Fundamental and Application-Oriented Research on Gamma Alloys 123
R. Yang
Deformation of PST Crystals of Ti46A18Nb and Ti46A18Ta 135
Y. Guo, R. Liu, H. Jin, R. Yang, A. Huang, and M. Loretto
Seeded Growth of Ti-47Al-2Cr-2Nb PST Crystals 143
H. Jin, R. Liu, Y. Cui, Q. Xian, D. Xu, and R. Yang
Textures of Rectangular Extrusions of Ti-47Al-2Cr-2Nb-0.15B 149
R. Liu, D. Liu, J. Tan, Y. Cui, and R. Yang
Microstructure and Properties
Origin and Magnitude of Internal Stresses in TiAl Alloys 161
R. Hoppe, and F. Appel
Effects of Microstructure, Alloying and C and Si Additions on Creep of Gamma TiAl Alloys 169
Y. Kim, and S Kim
Microstructure and Properties of Cast Ti-46Al-8Ta Alloy 179
J. Lapin, Z. Gabalcova, O. Bajana, T. Pelachova, H. Stanekova, and K. Frkanova
Effect of the Microstructure on the Deformation and Fatigue Damage in a Gamma-TiAl Produced by Additive Manufacturing Metallurgy Ti-47 Al-2Cr-2Nb-0.15B 189
M. Filippini, S. Beretta, L. Patriarca, and S. Sabbadini
Effect of Powder Pre-Treatment on the Mechanical Properties of Powder 195
L. Xu, J. Wu, Y. Cui, and R. Yang
Microstructure and Mechanical Properties of TiAl Alloys Produced by Powder Metallurgy 203
F. Kong, N. Cui, Y. Chen, D. Zhang, and Y. Su
Author Index 207
Subject Index 209
About the Author :
Young-Won Kim, Gamteck Gamma Alloy Technology, USA. Wilfried Smarsly, MTU Aero Engines, Germany.
Junpin Lin, University of Science and Technology Beijing, China.
Dennis M. Dimiduk, U.S. Air Force Research Laboratory, USA./p>
Fritz Appel, Helmholtz Zentrum Geesthacht, Germany.
