Abstract
The creep behaviour of a monolithic molybdenum disilicide has been investigated within a temperature range from 1100 °C to 1250 °C at applied stresses from 20 MPa to 100 MPa in air using the impression test method. The strain-time relationships have been recorded, and the creep exponents as well as the activation energies of creep have been calculated. The results are compared to the creep results of the same material tested in four-point bending mode. The stress exponent in impression was found to be approximately 1, and the apparent activation energy approximately 250 kJmol^-1. In lower stress-temperature range the creep behaviour of MoSi₂ in impression and bending mode is very similar, however at higher stress-temperature range the creep rate, stress exponent and activation energy are significantly lower in impression.

Key words
impression creep, molybdenum disilicide, stress exponent, activation energy

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