Development of a Low-Cost Third Generation Single Crystal Superalloy DD9

The tensile properties of a low-cost first generation single crystal superalloy DD16 have been investigated. The results show that values of the tensile strength and yield strength of DD16 alloy were similar at typical temperatures; from room temperature to 760, the yield strength of DD16 alloy increases; However, above 760, the yield strength of DD16 alloy decreases remarkably, and the maximum of the yield strength was 1145.5MPa at 760. From room temperature to 760, the fracture mode was cleavage fracture; But above 760, the fracture characteristics changed from cleavage to dimple.

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Transverse Tensile Properties of a Nickel-based Third Generation Single Crystal Superalloy

Rare Metal Materials and Engineering ◽

10.1016/s1875-5372(18)30218-2 ◽

2018 ◽

Vol 47 (10) ◽

pp. 2964-2969

Author(s):

Yang Wanpeng ◽

Li Jiarong ◽

Liu Shizhong ◽

Shi Zhenxue ◽

Zhao Jinqian ◽

...

Keyword(s):

Single Crystal ◽

Tensile Properties ◽

Single Crystal Superalloy ◽

Third Generation ◽

Transverse Tensile

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Optimization of Ta Content of a Third Generation Ni3Al Base Single Crystal Superalloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.816.304 ◽

2015 ◽

Vol 816 ◽

pp. 304-309

Author(s):

Song Ming Han ◽

Wei Li ◽

Yue Ma ◽

Xin Bao Zhao ◽

Shu Suo Li ◽

...

Keyword(s):

Single Crystal ◽

Thermodynamic Calculation ◽

Volume Fraction ◽

Primary Dendrite ◽

Solution Treatment ◽

Experimental Results ◽

Single Crystal Superalloy ◽

Third Generation ◽

Primary Dendrite Arm Spacing ◽

Calculation Results

In order to optimize the Ta content of a newly developed 3rd generation Ni3Al-based single crystal superalloy, a series of alloys with the varying of Ta content of 3.0, 4.2, 4.5, 6.0wt. % were prepared. The experimental results showed that with the addition of Ta, the size and volume fraction of bulky γ' phase significantly increased while the primary dendrite arm spacing decreased. Meanwhile, the difficulty of solution treatment significantly increased with increasing Ta content. And the thermodynamic calculation results showed that the volume fractions of γ' phase in this series of alloys were significantly higher than those of typical Ni based single crystal superalloys, indicating that the 3rd generation Ni3Al based single crystal superalloys can serve in the temperature of 1150oC to 1200oC.

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Effects of Surface Recrystallization on the Microstructures and Creep Properties of Single Crystal Superalloy DD6

Materials Science Forum ◽

10.4028/www.scientific.net/msf.638-642.2279 ◽

2010 ◽

Vol 638-642 ◽

pp. 2279-2284

Author(s):

Jia Rong Li ◽

Feng Li Sun ◽

Ji Chun Xiong ◽

Shi Zhong Liu ◽

Mei Han

Keyword(s):

Single Crystal ◽

Annealing Temperature ◽

Low Cost ◽

Rupture Life ◽

Creep Rupture ◽

Single Crystal Superalloy ◽

Recrystallization Temperature ◽

Creep Properties ◽

Grit Blasting ◽

Rupture Properties

This work assesses the effects of the surface recrystallization of the processing of water grit blasting, grit blasting and mechanically polishing on the microstructures and creep rupture properties of DD6 alloy, a low-cost second generation single crystal superalloy. The results demonstrate that the possibility and the depth of the surface recrystallization of DD6 show an increase as the annealing temperature increases from 1050°C to 1250°C. No surface recrystallization happens when the specimens of the alloy have been undergone at 1100°C for 4 hours after water grit blasting, but the surface recrystallization occurs at the annealing temperature above 1200°C for 4 hours after water grit blasting. The test indicates that the increasing pre-deformation decreases the surface recrystallization temperature. The creep rupture life of DD6 alloy without processing is 274.4 hours, 341.1 hours at the conditions of 980°C/250MPa, 1070°C/140MPa respectively. After annealing at 1100°C for 4 hours, the creep rupture life of the alloy with the processing of water grit blasting is equivalent to that of the alloy without processing. The surface recrystallization of the alloy happens with the processing of grit blasting after the annealing at 1100°C for 4 hours, and there is a reduction of the creep rupture life at the conditions as mentioned above. The creep properties of DD6 alloy meet the needs of blades and vanes of single crystal for advanced aeroengines when the surface recrystallization of the alloy occurs during manufacturing and processing.

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