Tensile Properties of Low Angle Boundaries of Single Crystal Superalloy DD6

The tensile properties of DD6 alloy with twist low angle boundaries were investigated at 760°C, 850°C and 980°C, and the misorientation angle of twist low angle boundaries of the specimens of the alloy varies from 0º to 12º. The results showed that when the angle of low angle boundaries is relatively small, it has a little effect on the tensile properties of the alloy. It is notable that effects of low angle boundaries on the tensile strength are weaker than those on the tensile elongation. The characteristic of quasi-cleavage, intergranular and dimple fracture were observed on the tensile rupture surfaces of the specimens, and the tensile fracture mechanism was discussed.

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Tensile Properties of a Low-Cost First Generation Single Crystal Superalloy DD16

Materials Science Forum ◽

10.4028/www.scientific.net/msf.747-748.478 ◽

2013 ◽

Vol 747-748 ◽

pp. 478-482 ◽

Cited By ~ 5

Author(s):

Jian Wei Xu ◽

Yun Song Zhao ◽

Ding Zhong Tang

Keyword(s):

Tensile Strength ◽

Yield Strength ◽

Single Crystal ◽

Tensile Properties ◽

Cleavage Fracture ◽

Room Temperature ◽

First Generation ◽

Low Cost ◽

Single Crystal Superalloy ◽

Fracture Characteristics

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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Mechanical Behaviour of a Single Crystal Superalloy DD32 - A Comparison with the Alloy SRR99

Materials Science Forum ◽

10.4028/www.scientific.net/msf.475-479.681 ◽

2005 ◽

Vol 475-479 ◽

pp. 681-684 ◽

Cited By ~ 3

Author(s):

Jin Jiang Yu ◽

Xiao Feng Sun ◽

Tao Jin ◽

Heng Rong Guan ◽

Zhuang Qi Hu

Keyword(s):

Single Crystal ◽

Tensile Properties ◽

Mechanical Behaviour ◽

Fracture Mechanism ◽

Stress Rupture ◽

Single Crystal Superalloy ◽

Directional Coarsening ◽

Temperature Capability ◽

Creep Temperature

Stress rupture and tensile properties of a single crystal superalloy DD32 are investigated comparing with the alloy SRR99. It is shown that the alloy DD32 offers an improved creep temperature capability of more than 60°C at higher stresses. The g¢ precipitates in the stress ruptured samples were rafted to P-N type directional coarsening. The fracture mechanism of the stress ruptured samples was initiated from the micropores.

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Tensile Behavior of Sintered Stainless Steel Fiber Felts: Effect of Sintering Joints and Fiber Ligaments

Metals ◽

10.3390/met8100768 ◽

2018 ◽

Vol 8 (10) ◽

pp. 768 ◽

Cited By ~ 1

Author(s):

Jun Ma ◽

Qiancheng Zhang ◽

Weidong Song ◽

Jianzhong Wang ◽

Huiping Tang ◽

...

Keyword(s):

Tensile Strength ◽

Stainless Steel ◽

Tensile Properties ◽

Bonding Strength ◽

Steel Fiber ◽

Tensile Elongation ◽

Tensile Fracture ◽

Practical Applications ◽

Tensile Fatigue ◽

Stainless Steel Fiber

To optimize the tensile properties of sintered 316L stainless steel fiber felts (SSFFs) which is important for their practical applications, the influence of sintering conditions on the microstructure (fiber ligament, sintering joint) and in turn, the tensile properties was investigated experimentally. It was shown that the tensile strength and tensile elongation of SSFFs were dominated by the tensile properties of the fiber ligaments and the bonding strength of the sintering joints. With the increase of sintering temperature versus holding time, the tensile strength of the fiber ligaments dropped significantly, while the sintering joints grew, producing a higher bonding strength between the fibers, resulting in more fibers being involved in the tensile process. These changes in sintering joints and fiber ligaments finally led to a relatively static ultimate strength of SSFFs with a significantly increased elongation, thus with a large increase in tensile fracture energy. The increase of size of the sintering joints also helped to considerably raise the tensile fatigue limit of 316L SSFFs. This research provides a basis to improve the mechanical properties of sintered 316L SSFFs in industrial production.

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Effects of Pouring Temperature on the Tensile Properties and Fracture Behavior of Single Crystal Superalloy DD6

Materials Science Forum ◽

10.4028/www.scientific.net/msf.788.511 ◽

2014 ◽

Vol 788 ◽

pp. 511-518

Author(s):

J.C. Xiong ◽

Jia Rong Li ◽

M. Han ◽

H.L. Yuan

Keyword(s):

Single Crystal ◽

Tensile Properties ◽

Fracture Mode ◽

Fracture Behavior ◽

Primary Dendrite ◽

Testing Temperature ◽

Single Crystal Superalloy ◽

Tensile Fracture ◽

Pouring Temperature ◽

Tensile Fracture Surface

The effects of pouring temperature on the microstructure and the tensile properties of single crystal superalloy DD6 were investigated. The results show that with the decrease of pouring temperature, the primary dendrite arm spacing increases, and the segregation ratio of main elements decreases obviously. DD6 alloy has the similar tensile behavior under the conditions of the pouring temperatures of 1520°C and 1570°C. The pouring temperature has little influence on the yield and ultimate strengths of DD6 alloy. The yield and ultimate tensile strengths of the specimens with the pouring temperature of 1520°C is little lower than the specimens with the pouring temperature of 1570°C under the testing temperatures at room temperature and 650°C, while the specimens with the pouring temperature 1520°C have higher yield and ultimate tensile strength when the testing temperature is higher than 760°C. The pouring temperature did not have an obvious influence on tensile fracture behavior. It has been observed that the tensile fracture surface belongs to quasi-cleaveage fracture mode at testing temperature of 760°C, but the mix characteristic of quasi-cleaveage fracture mode and dimple fracture mode at the testing temperature of 980°C.

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Improvement of Tensile Property of Ni-Based a Single Crystal Superalloy by Ru Addition

Materials Science Forum ◽

10.4028/www.scientific.net/msf.788.477 ◽

2014 ◽

Vol 788 ◽

pp. 477-482

Author(s):

Zhen Xue Shi ◽

Jia Rong Li ◽

Shi Zhong Liu ◽

Mei Han

Keyword(s):

Tensile Strength ◽

Single Crystal ◽

Tensile Property ◽

Single Crystal Superalloy ◽

Tensile Fracture ◽

Directionally Solidified ◽

Alloying Element ◽

Fracture Elongation ◽

Different Temperatures ◽

The Relationship

Two experimental single crystal superalloys, the Ru-free alloy and the Ru-containing alloy with [001] orientation, were prepared in a directionally solidified furnace, while other alloying element contents were kept unchanged. The effects of Ru on the microstructure and tensile property at 25°C, 760°C, 980°C and 1100°C of the single crystal superalloy were investigated. The results show that the size of γ′ particles became uniform, and the cubic shape of the particles turned a little regular after Ru addition. The yield and ultimate tensile strengths of the single crystal superalloy increased with variant degree at different temperatures. The fracture elongation and area deduction decreased at the testing temperatures of 25°C and 760°C, but those increased at 980°C and 1100°C. The tensile fracture mechanism of the single crystal superalloy at different temperature did not change. Finally the relationship between the improvement of tensile strength and Ru addition was discussed.

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Effect of Zr Addition on the Mechanical Properties and Superplasticity of a Forged SP700 Titanium Alloy

Materials ◽

10.3390/ma14040906 ◽

2021 ◽

Vol 14 (4) ◽

pp. 906

Author(s):

Dong Han ◽

Yongqing Zhao ◽

Weidong Zeng

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Titanium Alloy ◽

Tensile Properties ◽

Superplastic Deformation ◽

Volume Fraction ◽

Tensile Elongation ◽

Β Phase ◽

Zr Addition ◽

Fine Microstructure

The present study focuses on the effect of 1% Zr addition on the microstructure, tensile properties and superplasticity of a forged SP700 alloy. The results demonstrated that Zr has a significant effect on inhibiting the microstructural segregation and increasing the volume fraction of β-phase in the forged SP700 alloy. After annealing at 820 °C for 1 h and aging at 500 °C for 6 h, the SP700 alloy with 1% Zr showed a completely globular and fine microstructure. The yield strength, ultimate tensile strength and tensile elongation of the alloy with optimized microstructure were 1185 MPa, 1296 MPa and 10%, respectively. The superplastic deformation was performed at 750 °C with an elongation of 1248%. The improvement of tensile properties and superplasticity of the forged SP700 alloy by Zr addition was mainly attributed to the uniform and fine globular microstructures.

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Influences of the γ′ Phase on the Mechanical Properties of a Nickel-Based Single Crystal Superalloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1023.45 ◽

2021 ◽

Vol 1023 ◽

pp. 45-52

Author(s):

Xiao Yan Wang ◽

Meng Li ◽

Zhi Xun Wen

Keyword(s):

Mechanical Properties ◽

Solid Solution ◽

Single Crystal ◽

Tensile Properties ◽

Room Temperature ◽

Solution Treatment ◽

Single Crystal Superalloy ◽

Original Material ◽

Solid Solution Treatment ◽

The Matrix

After solid solution treatment at 1335°C for 4 hours and cooling to room temperature at different rate, the nickel-based single crystal superalloy were made into three kinds of nickel-based single crystal superalloy materials containing different size γ′ phases, respectively. The tensile test of I-shaped specimens was carried out at 980°C, and their effect of γ′ phase microstructure on the tensile properties was studied. The results show that the yielding strength of the material air-cooled to room temperature was lower than that with cooling rate at 0.15°C/s, but both of them were lower than the yielding strength of original material. Little difference was found on the elastic modulus of I-shaped specimens made of three kinds of materials. When the cubic degree of the γ′ phase is higher and the size is larger, the tensile properties of the material is better, which can be attributed to the larger size and narrower channel of the matrix phase that lead to higher dislocation resistance.

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Correlation Between Microstructure and Tensile Properties of STS 316L and Inconel 718 Fabricated by Selective Laser Melting (SLM)

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.18792 ◽

2020 ◽

Vol 20 (11) ◽

pp. 6807-6814

Author(s):

Jungsub Lee ◽

Minshik Lee ◽

Im Doo Jung ◽

Jungho Choe ◽

Ji-Hun Yu ◽

...

Keyword(s):

Tensile Strength ◽

Tensile Properties ◽

Selective Laser Melting ◽

Inconel 718 ◽

Tensile Elongation ◽

Processing Condition ◽

Processing Parameters ◽

Fusion Pore ◽

Laser Melting ◽

Track Width

The correlation between microstructure and tensile properties of selective laser melting (SLM) processed STS 316L and Inconel 718 were investigated at various heights (top, middle and bottom) and planes (YZ, ZX and XY). Columnar grains and dendrites were formed by directional growth during solidification. The average melt pool width and depth, and scan track width were similar in both specimens due to fixed processing parameters. SLM Inconel 718 has moderate tensile strength (1165 MPa) and tensile elongation (11.5%), whereas SLM STS 316L has outstanding tensile strength (656 MPa) and tensile elongation (75%) compared to other SLM processed STS 316L. Fine columnar diameter (0.5 μm) and dense microstructures (porosity: 0.35%) in SLM STS 316L promoted the enhancement of tensile elongation by suitable processing condition. Fractographic analysis suggested that the lack of fusion pore with unmelted powder should be avoided to increase tensile properties by controlling processing parameters.

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Microstructure Evolution of a Single Crystal Superalloy after Tensile Fracture at Different Temperature

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.721.262 ◽

2013 ◽

Vol 721 ◽

pp. 262-265

Author(s):

Zhen Xue Shi ◽

Shi Zhong Liu ◽

J. Yu ◽

M. Han ◽

J.R. Li

Keyword(s):

Single Crystal ◽

Microstructure Evolution ◽

Stacking Faults ◽

Single Crystal Superalloy ◽

Tensile Fracture ◽

Matrix Channel ◽

Stress Orientation ◽

Transmission Electron ◽

Strength Behavior ◽

The Matrix

The tensile property tests of DD6 single crystal superalloy were performed at 25°C, 760°C and 980°C in air. Detailed microstructure evolution was carried out on the alloy to illuminate the γ phase and dislocation structure after tensile fracture by scanning electron microscope and transmission electron microscopy. The results show that the alloy has the maximum tensile strength and the minimum plasticity at 760°C. DD6 alloy has the same anomalous yield strength behavior with other single crystal superalloys. The γ phase hasve a little extension in the stress orientation after tensile fracture at 25°C. The γ phase morphology still maintains cubic after tensile fracture at 760°C. The γ phase is no longer cubic and changes into rectangular solid in the specimen tensile ruptured at 980°C. The vertical γ matrix becomes thinner and horizontal γ matrix becomes thicker slightly. The γ phase is no longer cubic and changes into rectangular solid. High density dislocations are present in the matrix channels and a lot of superlattice stacking faults are seen within γ phases in the sample tested at 25°C. A large quantities of superlattice stacking faults within γ phase and a lot of dislocations tangling in matrix channel are all present in the sample tested at 760°C. The dislocation networks have homogeneously formed at γ/γ interface in the sample tested at 980°C.

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