ISSN: 0090-3973
Page Count: 9

Economical Creep Testing of Ultrahigh-temperature Alloys

Völkl, R
Dr.-Ing.,Friedrich-Schiller-University Jena,

Freund, D
Dipl.-Ing.,University of Applied Sciences Jena,

Fischer, B
Prof. Dr.-Ing. habil.,University of Applied Sciences Jena,

(Received 1 October 2001; accepted 26 August 2002)

Abstract

Specially designed facilities for creep testing of ultrahigh-temperature alloys are presented. Ohmic heating is chosen for easy access to the sample, quickly attainable heating and cooling rates, and simplicity in design and operation. Strain is measured with a video extensometer by means of the software SuperCreep. SuperCreep allows fast and automated analysis of creep curves. For short but precise representations of creep curves, Bézier splines are used. Creep tests on pure Pt, Pt-10 wt% Rh, and the oxide dispersion strengthened Pt-base alloys Pt DPH and Pt-10 wt% Rh DPH between 1200 and 1600°C have proven the reliability of the equipment. Stationary creep rates follow the Norton power law. Stress exponents, activation energies, and pre-exponential factors are given for the four alloys investigated.

Keywords:
test facility, strain measurement, video extensometer, image analysis, Bézier spline, high-temperature, creep, platinum, oxide exponents, strengthened alloys

Paper ID: JTE12351J
DOI: 10.1520/JTE12351J
ASTM International is a member of CrossRef.