Creep behaviour and microstructure changes of model cast Ni-Cr-W-C alloys

0367575 - ÚFM 2012 RIV NL eng J - Journal Article
Kvapilová, Marie - Kuchařová, Květa - Sklenička, Václav - Svoboda, Milan - Hrbáček, K.
Creep behaviour and microstructure changes of model cast Ni-Cr-W-C alloys.
Procedia Engineering. Roč. 10, - (2011), s. 839-844. E-ISSN 1877-7058.
[ICM11 -International Conference on The Mechanical Behavior of Materials /11./. Lake Como, 05.06.2011-09.06.2011]
Institutional research plan: CEZ:AV0Z20410507
Keywords : cast Ni based superalloy * creep properties * phase stability
Subject RIV: JG - Metallurgy

A comparative study of creep and microstructural properties of two model cast Ni-Cr-W-C alloys (Alloys A and B) resistant to high-temperature oxidation with different contents of Cr, W, Zr and Fe was performed. Uniaxial tensile creep tests were carried out at temperatures from 1023 to 1273 K and at the applied stresses ranged from 20 to 250 MPa. Creep tests were followed by microstructural and fractographic investigations. A mutual comparison between the creep characteristics of the alloys under comparable creep loading conditions shows that the alloy B with higher contents of tungsten and zirconium is more creep resistant as that of the Alloy A at lower temperatures. It is suggested that the alloy A and B earn their creep strength from the combination of solid solution hardening and precipitation hardening. However, it is difficult to quantify each contribution to the overall creep strength. Possible reason for the different consequence of strengthening effects is discussed.
Permanent Link: http://hdl.handle.net/11104/0202203