Remote Tracking of Phase Changes in Cr2AlC Thin Films by In-situ Resistivity Measurements

Abstract

Resistivity changes of magnetron sputtered, amorphous Cr 2 AlC thin films were measured during heating in vacuum. Based on correlative X-ray diffraction, in-situ and ex-situ selected area electron diffraction measurements and differential scanning calorimetry data from literature it is evident that the resistivity changes at 552 ± 4 and 585 ± 13 °C indicate the phase transitions from amorphous to a hexagonal disordered solid solution structure and from the latter to MAX phase, respectively. We have shown that phase changes in Cr 2 AlC thin films can be revealed by in-situ measurements of thermally induced resistivity changes.

Sputtering and Characterization of MAX‐Phase Forming Cr–Al–C and Ti–Al–C Coatings and Their Application on γ‐Based Titanium Aluminides

“…XRD measurements (shown in Figure 1b) at room temperature show that the coating is amorphous while reflections from the Al 2 O 3 substrate are visible, indicating that the substrate temperature of 255 C during deposition is too low to activate any crystallization processes in the coating. This is in agreement with previous investigations by Stelzer et al, [37] suggesting that a postheat treatment after deposition is necessary for the formation of the desired hexagonal Cr 2 AlC MAX-phase when deposited within this temperature range.…”

Autonomously Self‐Reporting Hard Coatings: Tracking the Temporal Oxidation Behavior of TiN by In Situ Sheet Resistance Measurements

“…Recently, changes in electrical resistance have been correlated to phase changes in Cr 2 AlC,19 while pioneering work by Rauh et al20 and Case21 conducted in the 1990s and 1980s showed that electrical resistance measurements are useful to study the initial stage of oxidation of 50–60 nm thick Cu20 and of 45 nm thick V21 films. In contrast to these sub‐100 nm investigations on metals, results of in situ measured sheet resistances will be employed to track the remaining film thickness of the approx.…”

Enhancing the high temperature oxidation behavior of Cr2AlC coatings by reducing grain boundary nanoporosity

“…This low temperature growth strategy resulted in the formation of X-ray amorphous coatings which were subsequently annealed at 600°C in a vacuum furnace evacuated to 0.15 mPa. According to Stelzer et al [15] this results in the formation of Cr 2 AlC MAX phase. Further deposition methodology related details can be found in [15].…”

“…According to Stelzer et al [15] this results in the formation of Cr 2 AlC MAX phase. Further deposition methodology related details can be found in [15]. Energy dispersive X-ray spectroscopy (EDX) data were acquired using an Oxford system within FEI Quanta 250F scanning electron microscope at an acceleration voltage of 12 kV.…”