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A creep test rig is described which allows to perform creep experiments with miniature tensile creep specimens under an inert gas atmosphere at temperatures up to 1150 8C. Previous work on the development of a miniature tensile creep test procedure is described. The key elements of the new inert gas system are then described. The test rig yields reliable creep data. Three examples for applications of the new system addressing grain boundary sliding in a TiAl alloy, creep cavitation and damage accumulation in copper and to provide high temperature creep data for a Co-Re-Cr alloy are given.

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A material family to replace the current superalloys in aeronautical gas turbine engines is considered to be that of gamma Titanium Aluminide (-TiAl) alloys. Structural components in aeronautical gas turbine engines typically experience large variations in temperatures and multiaxial states of stress under non-isothermal conditions. The uniaxial, torsional and bi-axial thermo-mechanical fatigue (TMF) behaviour of this -TiAl alloy have been examined at 400 – 800oC with strain amplitudes from 0.15% to 0.7%. The tests were conducted at both in-phase (IP) and out-of-phase (OP). The effects of TMF on the microstructure were also investigated. For the same equivalent mechanical strain amplitude uniaxial IP tests showed significantly longer lifetimes than pure torsional TMF tests. The non-proportional multiaxial OP test showed the lowest lifetimes at the same equivalent mechanical strain amplitude compared to the other types of tests.