TY - JOUR

T1 - The creep behavior of a fully lamellar γ-TiAl based alloy

AU - Burtscher, Michael

AU - Klein, Thomas

AU - Mayer, Svea

AU - Clemens, Helmut

AU - Fischer, Franz Dieter

PY - 2019/11/1

Y1 - 2019/11/1

N2 - Intermetallic γ-TiAl based alloys are in focus of interest because of their excellent mechanical properties at high temperatures in combination with their low density. Currently, they are used as turbine blades in aero engines at service temperatures up to around 1023 K. Therefore, the detailed knowledge of the creep behavior is of major interest. In this study, the influence of differently spaced fully lamellar microstructures on the creep behavior of an advanced micro-alloyed γ-TiAl based alloy, a so-called TNM+ alloy, is investigated. Creep tests at 1073 K using stresses of 150 and 200 MPa are conducted applying a constant load. In order to describe the creep behavior, a so-called one-parameter model, which uses the mean lamellar interface spacing as governing parameter, is adopted. The different lamellar spacings of the specimens are analyzed by means of transmission electron microscopy. Finally, based on a new constitutive law creep curves are calculated and compared with experimentally determined creep curves. The results are discussed in the light of existing literature.

AB - Intermetallic γ-TiAl based alloys are in focus of interest because of their excellent mechanical properties at high temperatures in combination with their low density. Currently, they are used as turbine blades in aero engines at service temperatures up to around 1023 K. Therefore, the detailed knowledge of the creep behavior is of major interest. In this study, the influence of differently spaced fully lamellar microstructures on the creep behavior of an advanced micro-alloyed γ-TiAl based alloy, a so-called TNM+ alloy, is investigated. Creep tests at 1073 K using stresses of 150 and 200 MPa are conducted applying a constant load. In order to describe the creep behavior, a so-called one-parameter model, which uses the mean lamellar interface spacing as governing parameter, is adopted. The different lamellar spacings of the specimens are analyzed by means of transmission electron microscopy. Finally, based on a new constitutive law creep curves are calculated and compared with experimentally determined creep curves. The results are discussed in the light of existing literature.

KW - Characterization

KW - Creep

KW - Electron microscopy

KW - Intermetallics

KW - Mechanical properties

KW - Microstructure

U2 - 10.1016/j.intermet.2019.106611

DO - 10.1016/j.intermet.2019.106611

M3 - Article

AN - SCOPUS:85072195119

VL - 114.2019

JO - Intermetallics

JF - Intermetallics

SN - 0966-9795

IS - November

M1 - 106611

ER -