Thermal Diffusivity Characteristics of the IN718 Alloy Tested with the Modified Pulse Method

The article presents the use of the modified pulse method (MPM) to determine the temperature characteristics of the thermal diffusivity of alloy 718. The experiment was carried out in the temperature range of 20-900 degrees C during the double heating of the sample with an interval of two weeks. The results of our own research showed a good correlation in the temperature range of 300-500 degrees C, during the first heating of the sample, with the recommended changes in thermal diffusivity by NPL & ASM and data from the MPDB database. On the other hand, clear deviations in the results occurred in the range of temperature changes up to about 300 degrees C, most likely responsible for the electron component of the conductivity of this alloy, and in the range above 700 degrees C, where there is a clear minimum that may be caused by the delta phase precipitation phenomenon.

Automated summary

This article presents the use of modified pulse method (MPM) to determine the temperature characteristics of thermal diffusivity of alloy 718. The experiment was conducted in the temperature range of 20-900 degrees C with double heating of the sample at a two-week interval. The research results showed good correlation between the recommended changes in thermal diffusivity by NPL & ASM and data from the MPDB database in the temperature range of 300-500 degrees C during the first heating of the sample. However, clear deviations occurred below 300 degrees C and above 700 degrees C, possibly due to the electron component of the alloy's conductivity and the precipitation phenomenon of the delta phase.