Creep Deformation of Allvac 718Plus

Hayes, Robert W.; Unocic, Raymond R.; Nasrollahzadeh, Maryam

doi:10.1007/s11661-014-2564-y

Creep Deformation of Allvac 718Plus

Journal Article · Mon Nov 10 23:00:00 EST 2014 · Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science

DOI:https://doi.org/10.1007/s11661-014-2564-y· OSTI ID:1286762

Hayes, Robert W. ^[1]; Unocic, Raymond R. ^[2]; Nasrollahzadeh, Maryam ^[1]

Metals Technology Inc., Northridge, CA (United States)
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Science (CNMS)

The creep deformation behavior of Allvac 718Plus was studied over the temperature range 650° to 732°C at initial applied stress levels ranging from 517 to 655 MPa. Over the entire experimental temperature stress regime this alloy exhibits Class M type creep behavior with all creep curves exhibiting a decelerating strain rate with strain or time throughout primary creep. However, unlike pure metals or simple solid solution alloys this gamma prime strengthened superalloy does not exhibit steady state creep. Rather, primary creep is instantly followed by a long duration of accelerating strain rate with strain or time. These creep characteristics are common amongst the gamma prime strengthened superalloys. Allvac 718Plus also exhibits a very high temperature dependence of creep rate. Detailed TEM examination of the deformation structures of selected creep samples reveals dislocation mechanisms similar to those found in high volume fraction gamma prime strengthened superalloys. Strong evidence of microtwinning is found in several of the deformation structures. The presence of microtwinning may account for the strong temperature dependence of creep rate observed in this alloy. In addition, due to the presence of Nb and thus, grain boundary delta phase, matrix dislocation activity which is not present in non Nb bearing superalloys occurs in this alloy. The creep characteristics and dislocation mechanisms are presented and discussed in detail.

View Accepted Manuscript (DOE)

Research Organization:: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS)

Sponsoring Organization:: USDOE Office of Science (SC)

Grant/Contract Number:: AC05-00OR22725

OSTI ID:: 1286762

Journal Information:: Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science, Journal Name: Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science Journal Issue: 1 Vol. 46; ISSN 1073-5623

Publisher:: ASM InternationalCopyright Statement

Country of Publication:: United States

Language:: English

References (19)

Microstructure and creep properties of dispersion-strengthened aluminum alloys Rösler, J.; Joos, R.; Arzt, E. Metallurgical Transactions A, Vol. 23, Issue 5 https://doi.org/10.1007/BF02647335	journal	May 1992
Precipitation of the δ-Ni3Nb phase in two nickel base superalloys Sundararaman, M.; Mukhopadhyay, P.; Banerjee, S. Metallurgical Transactions A, Vol. 19, Issue 3 https://doi.org/10.1007/BF02649259	journal	March 1988
Deformation and strength behavior of two nickel-base turbine disk alloys at 650 °C Sinharoy, Shubhayu; Virro-Nic, Pauline; Milligan, Walter W. Metallurgical and Materials Transactions A, Vol. 32, Issue 8 https://doi.org/10.1007/s11661-001-0014-0	journal	August 2001
Factors affecting the high temperature strength of polcyrystalline solids Sherby, O. D. Acta Metallurgica, Vol. 10, Issue 2 https://doi.org/10.1016/0001-6160(62)90058-5	journal	February 1962
Particle-coarsening, σ0 and tertiary creep Dyson, B. F.; McLean, M. Acta Metallurgica, Vol. 31, Issue 1 https://doi.org/10.1016/0001-6160(83)90059-7	journal	January 1983
Tertiary creep in nickel-base superalloys: analysis of experimental data and theoretical synthesis Dyson, B. F.; Gibbons, T. B. Acta Metallurgica, Vol. 35, Issue 9 https://doi.org/10.1016/0001-6160(87)90083-6	journal	September 1987
On the effects of heat treatments on the creep behaviour of a single crystal superalloy Caron, P.; Henderson, P. J.; Khan, T. Scripta Metallurgica, Vol. 20, Issue 6 https://doi.org/10.1016/0036-9748(86)90458-8	journal	June 1986
Mechanical behavior of crystalline solids at elevated temperature Sherby, Oleg D.; Burke, Peter M. Progress in Materials Science, Vol. 13 https://doi.org/10.1016/0079-6425(68)90024-8	journal	January 1968
The high temperature decrease of the critical resolved shear stress in nickel-base superalloys Kolbe, M. Materials Science and Engineering: A, Vol. 319-321 https://doi.org/10.1016/S0921-5093(01)00944-3	journal	December 2001
Investigation of creep deformation mechanisms at intermediate temperatures in René 88 DT Viswanathan, G. B.; Sarosi, P. M.; Henry, M. F. Acta Materialia, Vol. 53, Issue 10 https://doi.org/10.1016/j.actamat.2005.03.017	journal	June 2005
The role of grain boundaries in creep strain accumulation Wilshire, B.; Whittaker, M. T. Acta Materialia, Vol. 57, Issue 14 https://doi.org/10.1016/j.actamat.2009.05.009	journal	August 2009
Modeling displacive–diffusional coupled dislocation shearing of γ′ precipitates in Ni-base superalloys Zhou, Ning; Shen, Chen; Mills, Michael J. Acta Materialia, Vol. 59, Issue 9 https://doi.org/10.1016/j.actamat.2011.02.022	journal	May 2011
Microtwinning and other shearing mechanisms at intermediate temperatures in Ni-based superalloys Kovarik, L.; Unocic, R. R.; Li, Ju Progress in Materials Science, Vol. 54, Issue 6 https://doi.org/10.1016/j.pmatsci.2009.03.010	journal	August 2009
Diffusional Viscosity of a Polycrystalline Solid Herring, Conyers Journal of Applied Physics, Vol. 21, Issue 5 https://doi.org/10.1063/1.1699681	journal	May 1950
A Model for Boundary Diffusion Controlled Creep in Polycrystalline Materials Coble, R. L. Journal of Applied Physics, Vol. 34, Issue 6 https://doi.org/10.1063/1.1702656	journal	June 1963
Theory of Steady‐State Creep Based on Dislocation Climb Weertman, J. Journal of Applied Physics, Vol. 26, Issue 10 https://doi.org/10.1063/1.1721875	journal	October 1955
Steady‐State Creep through Dislocation Climb Weertman, J. Journal of Applied Physics, Vol. 28, Issue 3 https://doi.org/10.1063/1.1722747	journal	March 1957
An Evaluation of Deformation Models for Grain Boundary Sliding Langdon, Tg; Vastava, Rb Mechanical Testing for Deformation Model Development https://doi.org/10.1520/STP28901S	book	January 1982
Deformation Mechanisms in Ni-Base Disk Superalloys at Higher Temperatures Unocic, R. R.; Kovarik, L.; Shen, C. Superalloys 2008 (Eleventh International Symposium) https://doi.org/10.7449/2008/Superalloys_2008_377_385	conference	January 2008

Cited By (2)

Effects of Initial δ Phase on Creep Behaviors and Fracture Characteristics of a Nickel-Based Superalloy Lin, Y. C.; Yin, Liang-Xing; Luo, Shun-Cun Advanced Engineering Materials, Vol. 20, Issue 4 https://doi.org/10.1002/adem.201700820	journal	December 2017
Creep Failure and Damage Mechanism of Inconel 718 Alloy at 800–900 °C Chen, Kai; Dong, Jianxin; Yao, Zhihao Metals and Materials International https://doi.org/10.1007/s12540-019-00447-4	journal	September 2019

Similar Records

A TEM Study of Creep Deformation Mechanisms in Allvac 718Plus

Conference · Thu Dec 31 23:00:00 EST 2009 · OSTI ID:989713

Modelling of recovery controlled creep in nickel-base superalloy single crystals

Journal Article · Tue Dec 31 23:00:00 EST 1996 · Acta Materialia · OSTI ID:445329

Superalloys, supercomposites and superceramics

Book · Sat Dec 31 23:00:00 EST 1988 · OSTI ID:6726489

Related Subjects

36 MATERIALS SCIENCE
Allvac 718Plus
creep deformation behavior
gamma prime
superalloy

Creep Deformation of Allvac 718Plus

Citation Formats

References (19)

Cited By (2)

Similar Records

Related Subjects