Deformation and damage features of a Re/Ru-containing single crystal nickel base superalloy during creep at elevated temperature
| Autor: | Ning Tian, Guoqi Zhao, Shunke Zhang, Sugui Tian, Lirong Liu |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Shearing (physics)
Materials science Alloy 02 engineering and technology engineering.material 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Physics::Geophysics 0104 chemical sciences Superalloy Condensed Matter::Materials Science Deformation mechanism Creep Condensed Matter::Superconductivity lcsh:TA401-492 engineering lcsh:Materials of engineering and construction. Mechanics of materials General Materials Science Composite material Dislocation Deformation (engineering) 0210 nano-technology Single crystal |
| Zdroj: | Progress in Natural Science: Materials International, Vol 29, Iss 2, Pp 210-216 (2019) |
| ISSN: | 1002-0071 |
| DOI: | 10.1016/j.pnsc.2019.01.013 |
| Popis: | The deformation and damage features of a 4.5%Re/3.0%Ru-containing single crystal nickel-based superalloy during the creep in the temperature range of 1040–1070 °C and stress range of 137–180 MPa was investigated by means of creep properties measurement and contrast analysis of dislocation configuration. The results showed that the alloy exhibited a better creep resistance in the range of the testing temperatures and stresses, the deformation mechanism of the alloy during steady state creep was dislocations climbing over the rafted γ′ phase. In the latter period of creep, the deformation mechanism of the alloy was dislocations shearing into the rafted γ′ phase. It is believed that the dislocations shearing into γ′ phase may cross-slip from {111} to {100} planes for forming the K-W locks to restrain the slipping and cross-slipping of dislocations on {111} plane. 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 cracks along the γ/γ′ interfaces up to creep fracture, which is considered to be the damage and fracture feature of alloy during creep at high temperature. : In the later stage of the creep, the deformation mechanism of alloy is dislocations shearing into the rafted γ′ phase, and the dislocations shearing into γ′ phase may cross-slip from {111} to {100} planes to form the K-W locks. Wherein, the deformation mechanism of alloy during steady state creep is dislocations climbing over the rafted γ′ phase, and the strain rate of alloy during steady state creep is expressed as: ε˙=A″(VH)=A·D·h·B3(μ·b)2(1−υ)2H3exp(−Uj+Uvk·T). Keywords: Re/Ru alloying, Single crystal nickel-based superalloy, Creep, Dislocations climbing, K-W locks |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect