Small punch creep in Fe28Al3Cr0.02Ce alloy

Small punch testing of Fe3Al-based intermetallic alloy with Cr, Mn and Ce additions was performed in temperature range 773–873 K. It is shown that the testing procedure enables to study the creep properties of the alloy. The time dependence of the central deflection resembles creep curves observed in conventional uniaxial creep testing and the minimum deflection rate can be determined. Similarly as in conventional creep tests, the deflection process is then analyzed in terms of the activation energy and force exponent. In accordance with the phase structure of the alloy, two distinct areas can be observed. In the B2 range, the activation energy equals 181 kJ/mol; the force exponent is about 4.6. In the DO3 range, the activation energy equals 82 kJ/mol and the stress exponent is about 44. The transformation temperature DO3⇔B2 is close to 812 K. The technique can be used for an estimation of creep resistance.