Kinetics of creep damage accumulation induced by a room-temperature plastic deformation introduced during processing of AM1 Ni-based single crystal superalloy

Taking nickel-based single crystal superalloy DD6 as the research object, different degrees of creep damage were prefabricated by creep interruption tests, and then the creep damage was repaired by the restoration heat treatment system of solid solution heat treatment and two-stage aging heat treatment. The results show that with the creep time increasing, the alloy underwent microstructure evolution including γ′ phase coarsening, N-type rafting and de-rafting. After the restoration heat treatment, the coarse rafted γ′ phase of creep damaged specimens dissolved, precipitated, grew up, and became cubic again. Except for the specimens with creep interruption of 100 h, the γ′ phase can basically achieve the same arrangement as the γ′ phase of the original sample. The comparison of the secondary creep test shows that the steady-state creep stage of the test piece after the restoration heat treatment is relatively increased, and the total creep life can reach the same level as the primary creep life. The high temperature creep properties of the tested alloy are basically recovered, and the restoration heat treatment effect is good.

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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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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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Preliminary Investigations of a High Temperature Cu-13.3%Al-4%Ni Shape Memory Alloy Single Crystal

Applied Mechanics and Biomedical Technology ◽

10.1115/imece2003-42904 ◽

2003 ◽

Author(s):

Steve Trigwell ◽

Ganesh Kumara K. ◽

Abhijit Bhattacharyya ◽

Muhammed A. Qidwai

Keyword(s):

Plastic Deformation ◽

Shape Memory Alloy ◽

Single Crystal ◽

Shape Memory ◽

Room Temperature ◽

Alloy Single Crystal ◽

Stress Strain ◽

Stress Cycling ◽

Constitutive Response ◽

Martensite Reorientation

Preliminary investigations on the constitutive response of a Cu-13.3%Al-4%Ni (wt%) shape memory alloy single crystal with stress-free transformation temperatures around 100 to 150°C are reported. Room temperature stress cycling tests were carried out at very low deformation rates. Reproducible stress/strain curves of up to 9% strain due to detwinning (martensitematensite phase transformations) with no plastic deformation were obtained. The data also indicated that a period of stress cycling is required to stabilize the material before reproducible stress-strain curves are obtained due to martensite reorientation.

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Damage Accumulation at High Temperature Creep of a Single-Crystal Superalloy

Fracture of Nano and Engineering Materials and Structures ◽

10.1007/1-4020-4972-2_261 ◽

2008 ◽

pp. 527-528

Author(s):

A. Staroselsky ◽

B. Cassenti

Keyword(s):

High Temperature ◽

Single Crystal ◽

Damage Accumulation ◽

Single Crystal Superalloy ◽

High Temperature Creep ◽

Temperature Creep

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Tribological Properties of KDP Single Crystal

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.490-491.134 ◽

2014 ◽

Vol 490-491 ◽

pp. 134-137

Author(s):

Chun Peng Lu ◽

Hang Gao ◽

Xiao Ji Teng

Keyword(s):

Plastic Deformation ◽

Single Crystal ◽

Tribological Properties ◽

Room Temperature ◽

Surface Damage ◽

Kdp Crystal ◽

Scratch Tests ◽

Elastic And Plastic Deformation ◽

Kdp Crystals

Scratch tests on (001) face, doubler face and tripler face of KDP crystals are carried out at room temperature. It shows that the friction ceoffcients of different crystal faces are affected seriously by the crystal oritations, their variation periods of (001) face, doubler face and tripler face are 90o, 180o and 180o, their attitudes of relative anisotropy are 50%, 43.8% and 43.8%, and all of them are less than 0.4. The scratch mechanism of KDP crystal consists of four types: elastic and plastic deformation, ploughing, microchip, and surface damage. Differences between elastic and plastic deformation and ploughing are not obvious due to the soft-brittle nature of KDP crystal.

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