Nanoindentation of chemical-vapor deposited Al2O3 hard coatings at elevated temperatures

Operando reduction of elastic modulus in (Pr, Ce)O2− thin films

“…Here we quantified the elastic modulus of Pr 0. [35,36,37]. We correlated these results with oxygen vacancy concentration via a point defect and chemical expansion model developed previously for bulk PCO [2,3,18], and compared these experimental findings with our predictions based on DFT calculations of elastic constants for bulk compositions.…”

“…For this reason, statistical analysis of calculated elastic moduli for each set of samples and conditions was employed to identify significant changes in E as a function of elevated temperature, reduced oxygen partial pressure, and initial composition. The relatively higher variance at extreme temperatures is attributed chiefly to uncertainty in the accuracy of the probe geometric area function (contact area calibrated as a function of contact depth, as discussed below), and to slight differences in absolute temperature at the probe-sample interface for each replicate indentation site acquired over a span of 16-24 hr on a given sample surface[35,37]. Results presented herein include only thermally well-matched experiments, meaning that temperature stability was achieved for both the probe and sample in contact, as described in[58].…”

Temperature-dependent nanoindentation response of materials

“…[32] α-Al 2 O 3 Significant decrease of hardness (∼36%) and a slight decrease of Young's modulus at 500°C; Slight increase of Young's modulus and hardness at 600°C due to oxidation of the substrate. [73] κ-Al 2 O 3 Constant hardness and Young's modulus up to 300°C, followed by a decrease of hardness (up to 700°C) and Young's modulus (up to 500°C). [73] a-SiCN Drop of hardness up to 23% at 300°C for a-SiCN with low nitrogen (N) content, and up to 31% for the a-SiCN with high N content; Increase of elastic modulus at 650°C due to the pronounced effect of short-range ordering.…”

“…[73] κ-Al 2 O 3 Constant hardness and Young's modulus up to 300°C, followed by a decrease of hardness (up to 700°C) and Young's modulus (up to 500°C). [73] a-SiCN Drop of hardness up to 23% at 300°C for a-SiCN with low nitrogen (N) content, and up to 31% for the a-SiCN with high N content; Increase of elastic modulus at 650°C due to the pronounced effect of short-range ordering. [74] SiC Significant drop of hardness and slight decrease of elastic modulus up to 500°C.…”

A high temperature mechanical study on PH 13-8 Mo maraging steel

“…Nanoindentation at high temperature (HT) has been used for the last ten years and it has become a powerful technique to measure the mechanical properties at high temperatures such as hardness (H) and reduced modulus on a variety of different materials up to 700 and 750°C [14,15], but also other mechanical properties such as strain rate sensitivity (SRS or m-value) and activation volume (V*) [16][17][18][19]. In recent studies, the latter properties have been used to study the governing mechanism of deformation by different nanoindentation methods, such as strain rate jump, constant strain rate or constant load [16][17][18]20].…”