Influence of Stacking Fault Energy on Creep Mechanism of a Single Crystal Nickel-Based Superalloy Containing Re

2012 ◽  
Vol 706-709 ◽  
pp. 2474-2479 ◽  
Author(s):  
Su Gui Tian ◽  
Ben Jiang Qian ◽  
Yong Su ◽  
Hui Chen Yu ◽  
Xing Fu Yu
Keyword(s):  
Single Crystal ◽  
Deformation Mechanism ◽  
Partial Dislocation ◽  
Stacking Fault ◽  
Stacking Fault Energy ◽  
Creep Mechanism ◽  
Dislocation Configuration ◽  
Creep Properties ◽  
Nickel Based Superalloy ◽  
Contrast Analysis

By means of calculating stacking fault energy (SFE), measuring creep properties and contrast analysis of dislocation configuration, an investigation has been made into the influence of the stacking fault energy on the creep mechanism of the single crystal nickel-based superalloy. Results show that the alloy at 760¡æ has a lower stacking fault energy (SFE), and the SFE of the alloy increases with the temperatures. The deformed mechanism of the alloy during creep at 760¡æ is the cubical γ′ phase sheared by <110> super-dislocation which may be decomposed to form the configuration of (1/3)<112> super-Shockley partials dislocation plus the superlattice intrinsic stacking fault (SISF). The deformed mechanism of the alloy which possesses the higher SFE at 1070¡æ is the screw or edge super-dislocation shearing into the rafted γ′ phase. The SFE of the alloy at 980¡æ is intervenient between the ones of 760¡æ and 1070¡æ, the deformation mechanism of the alloy during creep is the rafted γ′ phase sheared by <110> screw and edge super-dislocations which may be decomposed into the configuration of (1/2)<110> partial dislocation plus APB.

Creep Behavior of a Ru-Free Nickel-Based Single Crystal Superalloy at Medium Temperatures

2017 ◽  
Vol 893 ◽  
pp. 212-217 ◽  
Author(s):  
Shuang Liang ◽  
Zhi Xin Liu
Keyword(s):  
Single Crystal ◽  
Creep Behavior ◽  
Diffusion Rate ◽  
Stacking Fault ◽  
Single Crystal Superalloy ◽  
Effect Factors ◽  
Dislocation Configuration ◽  
Screw Dislocations ◽  
Creep Curves ◽  
Contrast Analysis

By means of creep curves measurement and diffraction contrast analysis of dislocation configurations, the creep behavior and effect factors of a Ru-free nickel-based single crystal superalloy within the temperature range of 740~780°C are investigated. Results indicated that, the cubical γ′ phase transformed into the bunch-like structure. During creep at 760°C/750Mpa, no rafted features of γ′ phase is detected, but the degree of distortion of the cubic γ′ phase near fracture regions is increased. During creep, more super-dislocations shearing into γ′ phase of Ru-free alloy are decomposed on {111} plane to form the partials plus stacking fault, which is attributed to the interaction of the elements to decrease the stacking fault energy of the alloy. Moreover, the screw dislocations shearing into γ' phase of Ru-free alloy during creep at 760 °C may cross-slip from {111} to {100} planes for decomposing to form the configuration of the K-W locks, which is attributed to the higher alloying extent for decreasing the diffusion rate of elements. And the dislocation configuration may restrain the slipping of them to improve the creep resistance of alloy due to the non-plane core structure of them.

Creep Damage of a Re/Ru-Containing Single Crystal Nickel-Based Superalloy at Elevated Temperature

2019 ◽  
Vol 795 ◽  
pp. 123-129
Author(s):  
Guo Qi Zhao ◽  
Su Gui Tian ◽  
Shun Ke Zhang ◽  
Ning Tian ◽  
Li Rong Liu
Keyword(s):  
High Temperature ◽  
Elevated Temperature ◽  
Single Crystal ◽  
Deformation Mechanism ◽  
Creep Resistance ◽  
Creep Damage ◽  
Stress Axis ◽  
Dislocation Configuration ◽  
Nickel Based Superalloy ◽  
Damage And Fracture

By means of creep properties measurement, microstructure observation and contrast analysis of dislocation configuration, the creep behavior of a 4.5%Re/3.0%Ru-containing single crystal nickel-based superalloy at elevated temperature is investigated. Results show that the creep life of the alloy at 1040°C/160MPa is measured to be 725h to exhibit a better creep resistance at high temperature. In the primary stage of creep at high temperature, the γ phase in alloy has transformed into the N-type rafted structure along the direction vertical to the stress axis, the deformation mechanism of alloy during steady state creep is dislocations slipping in γ matrix and climbing over the rafted γ phase. In the latter period of creep, the deformation mechanism of alloy is dislocations slipping in γ matrix and shearing into the rafted γ phase. Wherein the dislocations shearing into the γ phase may cross-slip from {111} to {100} planes for forming the K-W locks to restrain the slipping and cross-slipping on {111} plane, which is thought to be the main reason of the alloy having a better creep resistance. As the creep goes on, the alternate slipping of dislocations results in the twisted of the rafted γ phase to promote the initiation and propagation of the cracks along the interfaces of γ/γ phase up to creep fracture, which is thought to be the damage and fracture mechanism of alloy during creep at high temperature.

The effect of thickness on the creep properties of a single-crystal nickel-based superalloy

2018 ◽  
Vol 728 ◽  
pp. 124-132 ◽  
Author(s):  
Yebing Hu ◽  
Li Zhang ◽  
Tieshan Cao ◽  
Congqian Cheng ◽  
Pengtao Zhao ◽  
...  
Keyword(s):  
Single Crystal ◽  
Creep Properties ◽  
Nickel Based Superalloy

First-principle study of stacking fault energy for ZnSe single crystal

2015 ◽  
Vol 96 ◽  
pp. 81-84
Author(s):  
Cuixia Liu ◽  
Zengyun Jian ◽  
Man Zhu ◽  
Lianyang Chen
Keyword(s):  
Single Crystal ◽  
Stacking Fault ◽  
Stacking Fault Energy ◽  
First Principle ◽  
Znse Single Crystal

Creep Behaviors of a Single Crystal Nickel-Based Superalloy Containing 4.2%Re

2011 ◽  
Vol 689 ◽  
pp. 276-281 ◽  
Author(s):  
Su Gui Tian ◽  
Ben Jiang Qian ◽  
Fu Shun Liang ◽  
An An Li ◽  
Xing Fu Yu
Keyword(s):  
Single Crystal ◽  
Applied Stress ◽  
Microstructure Evolution ◽  
Deformation Mechanism ◽  
Stress Axis ◽  
Steady Creep ◽  
Nickel Based Superalloy ◽  
Microstructure Observation ◽  
Creep Curves ◽  
Main Deformation

By the measurement of creep curves and microstructure observation, an investigation has been made into the creep behaviors and microstructure evolution of a single crystal nickel-based superalloy containing 4.2%Re. Results show that the superalloy displays an obvious sensibility on the applied temperatures and stresses in the range of the applied temperatures and stresses. During the initial creep, the cubical g¢ phase in the alloy is transformed into an N-type rafted structure along the direction vertical to the applied stress axis. After crept up to fracture, the rafted g¢ phase in the region near fracture is transformed into a twisted configuration. The dislocation climbing over the rafted g¢ phase is considered to be the main deformation mechanism of the alloy during the steady creep state, and dislocations shear into the rafted g¢ phase is the main deformation mechanism of the alloy in the later stage of creep.

Sign in / Sign up

Export Citation Format

Share Document