CREEP-FATIGUE CRACK GROWTH AND FRACTOGRAPHY OF METALLIC MATERIALS IN AIR AND VACUUM AT ELEVATED TEMPERATURES

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.

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Creep-fatigue crack growth behavior of Pb-contained and Pb-free solders at room and elevated temperatures

Procedia Engineering ◽

10.1016/j.proeng.2011.04.206 ◽

2011 ◽

Vol 10 ◽

pp. 1238-1243 ◽

Cited By ~ 8

Author(s):

K. Fakpan ◽

Y. Otsuka ◽

Y. Mutoh ◽

S. Inoue ◽

K. Nagata ◽

...

Keyword(s):

Fatigue Crack ◽

Fatigue Crack Growth ◽

Crack Growth ◽

Elevated Temperatures ◽

Growth Behavior ◽

Crack Growth Behavior ◽

Fatigue Crack Growth Behavior ◽

Creep Fatigue ◽

Creep Fatigue Crack

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Creep–Fatigue Crack Growth Behavior of Pb-Containing and Pb-Free Solders at Room and Elevated Temperatures

Journal of Electronic Materials ◽

10.1007/s11664-012-2061-2 ◽

2012 ◽

Vol 41 (9) ◽

pp. 2463-2469 ◽

Cited By ~ 8

Author(s):

Kittichai Fakpan ◽

Yuichi Otsuka ◽

Yoshiharu Mutoh ◽

Shunsuke Inoue ◽

Kohsoku Nagata ◽

...

Keyword(s):

Fatigue Crack ◽

Fatigue Crack Growth ◽

Crack Growth ◽

Elevated Temperatures ◽

Growth Behavior ◽

Crack Growth Behavior ◽

Fatigue Crack Growth Behavior ◽

Creep Fatigue ◽

Creep Fatigue Crack

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Fatigue and creep-fatigue crack growth in alloy 709 at elevated temperatures

Materials at High Temperatures ◽

10.1080/09603409.2019.1664079 ◽

2019 ◽

Vol 36 (6) ◽

pp. 562-574 ◽

Cited By ~ 1

Author(s):

N. Shaber ◽

R. Stephens ◽

J. Ramirez ◽

G. P. Potirniche ◽

M. Taylor ◽

...

Keyword(s):

Fatigue Crack ◽

Fatigue Crack Growth ◽

Crack Growth ◽

Elevated Temperatures ◽

Creep Fatigue ◽

Creep Fatigue Crack

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Evaluating the Critical Temperature of Creep-Fatigue Interaction a Nickel-Based Powder Metallurgy Superalloy

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.577-578.625 ◽

2013 ◽

Vol 577-578 ◽

pp. 625-628

Author(s):

Hao Liu ◽

Rui Bao ◽

Wei Ming Lei ◽

Bin Jun Fei

Keyword(s):

Fatigue Crack ◽

Critical Temperature ◽

Powder Metallurgy ◽

Fatigue Crack Growth ◽

Crack Growth ◽

Elevated Temperatures ◽

Fatigue Loading ◽

Damage Mechanism ◽

Creep Fatigue ◽

Creep Fatigue Crack

For the components working in high temperature and enduring fatigue loading, the fatigue fracture properties will be reduced remarkably when the working temperature is higher than the critical temperature of creep-fatigue interactionTcof the material. In consequence, the damage mechanism from creep-fatigue interaction becomes more complex. A method is presented in this paper to determine theTcof a nickel-based powder metallurgy superalloy. Pure fatigue crack growth and creep-fatigue crack growth tests were conducted in several different elevated temperatures. The fracture mechanism was investigated via observing the fractographic characteristics using scanning electron microscope (SEM). The test results show that theTcof this superalloy is a little bit lower than a half of the melting temperatureTm.

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