Gamma Prime Particle Coarsening Behavior at Elevated Temperatures in Cast Nickel-Based Superalloy, GTD-111 EA

2008 ◽  
Vol 27 (1) ◽  
Author(s):  
P. Wangyao ◽  
S. Polsilapa ◽  
P. Chaishom ◽  
J. Zrnik ◽  
W. Homkrajai ◽  
...  
Keyword(s):  
Elevated Temperatures ◽  
Particle Coarsening ◽  
Gamma Prime ◽  
Nickel Based Superalloy ◽  
Coarsening Behavior

scholarly journals Microstructural Development and Coarsening Behavior of γ′ Precipitates in Co–Ni–Al–W-Base ODS Alloys

2012 ◽  
Vol 53 (11) ◽  
pp. 1922-1928 ◽  
Author(s):  
Lin Zhang ◽  
Xuanhui Qu ◽  
Mingli Qin ◽  
Rafi-ud-din ◽  
Xinbo He ◽  
...  
Keyword(s):  
Microstructural Development ◽  
Gamma Prime ◽  
Coarsening Behavior ◽  
Ods Alloys

Oxidation of Alloy-X in Subcritical, Transition, and Supercritical Water

CORROSION ◽  
10.5006/3881 ◽  
2021 ◽  
Author(s):  
Zachary Karmiol ◽  
Dev Chidambaram
Keyword(s):  
Supercritical Water ◽  
Photoelectron Spectroscopy ◽  
Focused Ion Beam ◽  
Elevated Temperatures ◽  
Subcritical Water ◽  
Ion Beam ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nickel Based Superalloy ◽  
Before And After

This work investigates the oxidation of a nickel based superalloy, namely Alloy X, in water at elevated temperatures: subcritical water at 261°C and 27 MPa, the transition between subcritical and supercritical water at 374°C and 27 MPa, and supercritical water at 380°C and 27 MPa for 100 hours. The morphology of the sample surfaces were studied using scanning electron microscopy coupled with focused ion beam milling, and the surface chemistry was investigated using X-ray diffraction, Raman spectroscopy, energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy before and after exposure studies. Surfaces of all samples were identified to comprise of a ferrite spinel containing aluminum.

scholarly journals Creep rupture properties of bare and coated polycrystalline nickel-based superalloy Rene®80

2021 ◽  
pp. 36-36
Author(s):  
M.M. Barjesteh ◽  
S.M. Abbasi ◽  
K.Z. Madar ◽  
K. Shirvani
Keyword(s):  
Elevated Temperatures ◽  
Life Time ◽  
Creep Rupture ◽  
Polycrystalline Nickel ◽  
Creep Life ◽  
Nickel Based Superalloy ◽  
Platinum Aluminide ◽  
Rupture Properties ◽  
Low Activity ◽  
Rupture Behavior

Creep deformation is one of the life time limiting reasons for gas turbine parts that are subjected to stresses at elevated temperatures. In this study, creep rupture behavior of uncoated and platinum-aluminide coated Rene?80 has been determined at 760?C/657 MPa, 871?C/343 MPa and 982?C/190 Mpa in air. For this purpose, an initial layer of platinum with a thickness of 6?m was applied on the creep specimens. Subsequently, the aluminizing were formed in the conventional pack cementation method via the Low Temperature-High Activity (LTHA) and High Temperature-Low Activity (HTLA) processes. Results of creep-rupture tests showed a decrease in resistance to creep rupture of coated specimen, compared to the uncoated ones. The reductions in rupture lives in LTHA and HTLA methods at 760?C/657 MPa, 871?C/343 MPa and 982?C/190 MPa were almost (26% and 41.8%), (27.6% and 38.5%) and (22.4% and 40.3%), respectively as compared to the uncoated ones. However, the HTLA aluminizing method showed an intense reduction in creep life. Results of fractographic studies on coated and uncoated specimens indicated a combination of ductile and brittle failure mechanisms for all samples. Although, the base failure mode in substrate was grain boundary voids, cracks initiated from coating at 760?C/657MPa and 871?C/343. No cracking in the coating was observed at 982?C/190MPa.

scholarly journals A Concise Binomial Model for Nonlinear Creep-Fatigue Crack Growth Behavior at Elevated Temperatures

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 651
Author(s):  
Jianxing Mao ◽  
Zhixing Xiao ◽  
Dianyin Hu ◽  
Xiaojun Guo ◽  
Rongqiao Wang
Keyword(s):  
Fatigue Crack ◽  
Fatigue Crack Growth ◽  
Crack Growth ◽  
Dwell Time ◽  
Elevated Temperatures ◽  
Nonlinear Creep ◽  
Nickel Based Superalloy ◽  
Proposed Model ◽  
Creep Fatigue ◽  
Creep Fatigue Crack

The creep-fatigue crack growth problem remains challenging since materials exhibit different linear and nonlinear behaviors depending on the environmental and loading conditions. In this paper, we systematically carried out a series of creep-fatigue crack growth experiments to evaluate the influence from temperature, stress ratio, and dwell time for the nickel-based superalloy GH4720Li. A transition from coupled fatigue-dominated fracture to creep-dominated fracture was observed with the increase of dwell time at 600 °C, while only the creep-dominated fracture existed at 700 °C, regardless of the dwell time. A concise binomial crack growth model was constructed on the basis of existing phenomenal models, where the linear terms are included to express the behavior under pure creep loading, and the nonlinear terms were introduced to represent the behavior near the fracture toughness and during the creep-fatigue interaction. Through the model implementation and validation of the proposed model, the correlation coefficient is higher than 0.9 on ten out of twelve sets of experimental data, revealing the accuracy of the proposed model. This work contributes to an enrichment of creep-fatigue crack growth data in the typical nickel-based superalloy at elevated temperatures and could be referable in the modeling for damage tolerance assessment of turbine disks.

Effect of cooling rates of solution treatment on rejuvenation heat-treated microstructures of a cast nickel-based superalloy

2021 ◽  
Vol 63 (2) ◽  
pp. 105-112
Author(s):  
Chuleeporn Paa-rai ◽  
Gobboon Lothongkum ◽  
Panyawat Wangyao
Keyword(s):  
Solution Treatment ◽  
Spherical Shape ◽  
Irregular Shape ◽  
Air Cooling ◽  
Gamma Prime ◽  
Nickel Based Superalloy ◽  
Heat Treated ◽  
Two Temperatures ◽  
Cooling Media

Abstract IN-738 turbine blade samples, deteriorated after long term service at high temperatures, were solution heat-treated at two temperatures, 1398 K and 1473 K, for 7.2 ks. Subsequently, the samples were cooled down in different atmospheres, in air and in furnace, for the purpose of studying the effects of different cooling media (rates) on the restored microstructures. Following this, the samples were aged at 1118 K for 43.2 ks and 86.4 ks in order to determine the characteristic of re-precipitated gamma prime particles. A scanning electron microscope (SEM) and ImageJ analysis software were used. The results show that the cooling in air provided gamma prime particles re-precipitating in spherical shape while the cooling in a furnace resulted in coarse gamma prime particles re-precipitating in irregular shape. The samples solutionized at 1398 K for 7.2 ks cooled down in air and then aging at 1118 K provided bimodal microstructure, while the sample solutionized at 1473 K for 7.2 ks, followed by air cooling and aging at 1118 K generated unimodal γ’ precipitation in spherical shape. Cooling in a furnace provides coarse γ’ recipitated particles in more irregular shape for the both solutionizing temperatures studied here. Cooling in a furnace provides coarse γ’ precipitated particles in more irregular shape for the both solutionizing temperatures studied here.

The effect of heat treatment on characteristics of the gamma prime phase and hardness of the nickel-based superalloy Rene®80

2019 ◽  
Vol 227 ◽  
pp. 46-55 ◽  
Author(s):  
Mohammad Mehdi Barjesteh ◽  
Seyed Mehdi Abbasi ◽  
Karim Zangeneh Madar ◽  
Kourosh Shirvani
Keyword(s):  
Heat Treatment ◽  
Gamma Prime ◽  
Nickel Based Superalloy ◽  
Prime Phase

scholarly journals Fracture Mechanism in Fatigue of Nickel-Based Superalloy Inconel 718 at Elevated Temperatures

2007 ◽  
Vol 1 (6) ◽  
pp. 734-743 ◽  
Author(s):  
Norio KAWAGOISHI ◽  
Qiang CHEN ◽  
Nu YAN ◽  
Masahiro GOTO ◽  
Qingyuan WANG ◽  
...  
Keyword(s):  
Fracture Mechanism ◽  
Inconel 718 ◽  
Elevated Temperatures ◽  
Nickel Based Superalloy

Long-Term Gamma Prime Phase Stability after Various Heat Treatment Conditions with Temperature Dropping during Solution Treatment in Cast Nickel Base Superalloy, Grade Inconel-738

2017 ◽  
Vol 891 ◽  
pp. 420-425
Author(s):  
Sureerat Polsilapa ◽  
Aimamorn Promboopha ◽  
Panyawat Wangyao
Keyword(s):  
Heat Treatment ◽  
Turbine Blades ◽  
Solution Treatment ◽  
Nickel Base Superalloy ◽  
Gamma Prime ◽  
Nickel Based Superalloy ◽  
Treatment Conditions ◽  
Nickel Base ◽  
Base Superalloy

Cast nickel based superalloy, Grade Inconel 738, is a material for turbine blades. Its rejuvenation heat treatment usually consist of solution treatment condition with temperature range of 1125-1205 oC for 2-6 hours. Then it is following with double aging process including primary aging at 1055oC for 1 hour and secondary aging at 845oC for 24 hours. However, the various selected temperature dropping program were performed during solution treatment to simulate the possible error of heating furnace. The maximum number of temperature dropping during solution treatment is varied from 1-3 times From all obtained results, the various temperature dropping during solution treatment conditions showed extremely the significant effect on the final rejuvenated microstructures and long-term gamma prime stability after heating at temperature of 900oC for 200 hours.

Sign in / Sign up

Export Citation Format

Share Document