This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Directional Solidification to Produce Columnar Grain and Single Crystal Structures
Annotation ability available
Sector:
Language:
English
Abstract
Something exciting has been happening during these last several years. Structural components of a major engineering device were first constructed so that each one consisted of an individual metal crystal. These were alloy single crystal turbine blades for advanced aircraft jet engines. A new precision-casting technique, based on directional solidification, which imparts significantly improved ductility and thermal shock resistance to high-temperature, creep-resistant, nickel-base superalloys, has been carried through from research to production. This controlled solidification technique has been used to produce both columnar grain and alloy single crystal gas turbine components.
The improvement in physical properties is achieved by controlling the solidification process to produce either columnar grains throughout a cast-to-size part, or a complete single crystal throughout a cast-to-size part, with a preferred [001] crystallographic orientation. This orientation is established parallel to the major stress axis of the part without the use of separate “seeding.” These parts have exhibited superior structural strength and stability in the severe operating environments associated with gas turbine engine operation. A comparison is made between the properties of superalloys having conventional equiaxed grains, directionally solidified columnar grains and [001] oriented single crystals.
The evolution of this new process is traced from its beginning in columnar grain directional solidification experiments through the pilot-plant operation. The feasibility of producing parts using the “directional solidification process” has been demonstrated in production foundry facilities where several thousand gas turbine blades and vanes have been cast-to-size in various complex shapes.
Authors
Topic
Citation
VerSnyder, F., "Directional Solidification to Produce Columnar Grain and Single Crystal Structures," SAE Technical Paper 700540, 1970, https://doi.org/10.4271/700540.Also In
References
- Barrett C. S. “Structure of Metals.” 2nd New York McGraw-Hill Book Co., Inc. 1952 9
- Piearcey B. J. VerSnyder F. L. “New Casting Techniques Strengthens Turbine Components.” SAE Journal 74 June 1966 84 87
- Piearcey B. J. VerSnyder F. L. “Single Crystal Alloy Extends Turbine Blade Service Life Four Times.” SAE Journal 74 June 1966 36 43
- VerSnyder F. L. Piearcey B. J. “A New Development in Gas Turbine Materials: The Properties and Characteristics of PWA 664.” AIAA Jrl. of Aircraft 3 5 Sept.-Oct. 1966 390 397
- Piearcey B. J. VerSnyder F. L. “A Breakthrough in Making Turbine Components … Directional Solidification and Single Crystals.” Metals Progress 90 November 1966 66 71
- VerSnyder F. L. Barrow R. B. Piearcey B. J. Sink L. W. “Directional Solidification in the Precision Casting of Gas-Turbine Parts.” Modern Castings 50 12 December 1967 360 367
- Piearcey B. J. VerSnyder F. L. “The Control of Grain Shape and Its Effect on the Properties of Cast Components For High-Temperature and High-Stress Applications.” SAE Transactions 75 1966 paper 660055
- Wells C. H. “The Elastic Constants of a Directionally-Solidified, Nickel-Base Superalloy, Mar-M200.” ASM Transactions Quarterly 60 June 1967 270 271
- Piearcey B. J. Terkelsen B. E. “The Effect of Uni-directional Solidification on the Properties of Cast Nickel-Base Superalloys.” Transactions Metallurgical Society AIME 239 August 1967 1143 1150
- Kear B. H. Piearcey B. J. “Tensile and Creep Properties of Single Crystals of the Nickel-Base Superalloy Mar-M200.” Transactions Metallurgical Society AIME 239 August 1967 1209 1215
- Piearcey B. J. Kear B. H. Smashey R. W. “Correlation of Structure with Properties in a Directionally Solidified Nickel-Base Superalloy.” ASM Transactions Quarterly 60 December 1967 634 645
- VerSnyder F. L. Barrow R. B. Piearcey B. J. Sink L. W. “Directional Solidification in the Precision Casting of Vacuum Melted Superalloys.” Foster E. L. Transactions Intl. Vacuum Metallurgy Conf. 1967 391 411
- VerSnyder F. L. “Directional Solidification and Mono-crystaloys.” McGraw-Hill Yearbook of Science and Technology 1968 193 196
- VerSnyder F. L. Barrow R. B. Piearcey B. J. Sink L. W. “Precision Casting of Alloy Single Crystal Gas-Turbine Parts.” AFS Transactions, Modern Castings 55 January 1969 10
- VerSnyder F. L. “Gas Turbine Element.” July 12 1966
- Piearcey B. J. “Heat Treatment of Alloys.” March 21 1967
- Lyons E. J. “Mold Heater.” Oct. 10 1967
- Parille D. R. “Core Location in Precision Casting.” Sept. 17 1968
- Barrow R. B. et al. “Induction Electric Mold Heater.” Oct. 8 1968
- Sink L. W. “Method of Casting Directionally Solidified Articles.” Dec. 24 1968