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Temperature dependent mechanical property of PZT film: an investigation by nanoindentation.

Li Y, Feng S, Wu W, Li F - PLoS ONE (2015)

Bottom Line: Its reduce modulus and hardness were calculated by the typical Oliver-Pharr method.Results show that the indentation depth and modulus increase, but the hardness decreases at elevated temperature.The increasing of true modulus is attributed to the reducing of recoverable indentation depth induced by back-switched domains.

View Article: PubMed Central - PubMed

Affiliation: Department of Engineering mechanics, School of Civil Engineering, Wuhan University, Wuhan, China; State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, China.

ABSTRACT
Load-depth curves of an unpoled Lead Zirconate Titanate (PZT) film composite as a function of temperature were measured by nanoindentation technique. Its reduce modulus and hardness were calculated by the typical Oliver-Pharr method. Then the true modulus and hardness of the PZT film were assessed by decoupling the influence of substrate using methods proposed by Zhou et al. and Korsunsky et al., respectively. Results show that the indentation depth and modulus increase, but the hardness decreases at elevated temperature. The increasing of indentation depth and the decreasing of hardness are thought to be caused by the decreasing of the critical stress needed to excite dislocation initiation at high temperature. The increasing of true modulus is attributed to the reducing of recoverable indentation depth induced by back-switched domains. The influence of residual stress on the indentation behavior of PZT film composite was also investigated by measuring its load-depth curves with pre-load strains.

No MeSH data available.


Related in: MedlinePlus

Topography micrographs of indentation impressions at 24°C, 200°C, 300°C, and 380°C.The cross-section curves of the indentation impressions were also plotted as inset figures.
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pone.0116478.g003: Topography micrographs of indentation impressions at 24°C, 200°C, 300°C, and 380°C.The cross-section curves of the indentation impressions were also plotted as inset figures.

Mentions: The topography micrographs of the indentation impressions were scanned after indentation. Fig. 3 shows the scanned results at 24°C, 200°C, 300°C and 380°C. The cross-section curves of the topography micrographs were also plotted in Fig. 3. It can be seen that at all temperature, slight pile-up was observed near the indent impression but no apparent cracks were observed, which means that the indentation load amplitude of 10mN is not large enough to induce cracks in the tested PZT film composite. Further, the residual indentation depth () measured by the cross-section curves increases at elevated temperature, but all of them are slightly smaller than the remnant depth (hr) measured by the load-depth curves. Additionally, the difference between hr and , namely decreases with increasing temperature, indicating some indentation depths were recovered after unloading and the recovery depth decreases with increasing temperature.


Temperature dependent mechanical property of PZT film: an investigation by nanoindentation.

Li Y, Feng S, Wu W, Li F - PLoS ONE (2015)

Topography micrographs of indentation impressions at 24°C, 200°C, 300°C, and 380°C.The cross-section curves of the indentation impressions were also plotted as inset figures.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4358891&req=5

pone.0116478.g003: Topography micrographs of indentation impressions at 24°C, 200°C, 300°C, and 380°C.The cross-section curves of the indentation impressions were also plotted as inset figures.
Mentions: The topography micrographs of the indentation impressions were scanned after indentation. Fig. 3 shows the scanned results at 24°C, 200°C, 300°C and 380°C. The cross-section curves of the topography micrographs were also plotted in Fig. 3. It can be seen that at all temperature, slight pile-up was observed near the indent impression but no apparent cracks were observed, which means that the indentation load amplitude of 10mN is not large enough to induce cracks in the tested PZT film composite. Further, the residual indentation depth () measured by the cross-section curves increases at elevated temperature, but all of them are slightly smaller than the remnant depth (hr) measured by the load-depth curves. Additionally, the difference between hr and , namely decreases with increasing temperature, indicating some indentation depths were recovered after unloading and the recovery depth decreases with increasing temperature.

Bottom Line: Its reduce modulus and hardness were calculated by the typical Oliver-Pharr method.Results show that the indentation depth and modulus increase, but the hardness decreases at elevated temperature.The increasing of true modulus is attributed to the reducing of recoverable indentation depth induced by back-switched domains.

View Article: PubMed Central - PubMed

Affiliation: Department of Engineering mechanics, School of Civil Engineering, Wuhan University, Wuhan, China; State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, China.

ABSTRACT
Load-depth curves of an unpoled Lead Zirconate Titanate (PZT) film composite as a function of temperature were measured by nanoindentation technique. Its reduce modulus and hardness were calculated by the typical Oliver-Pharr method. Then the true modulus and hardness of the PZT film were assessed by decoupling the influence of substrate using methods proposed by Zhou et al. and Korsunsky et al., respectively. Results show that the indentation depth and modulus increase, but the hardness decreases at elevated temperature. The increasing of indentation depth and the decreasing of hardness are thought to be caused by the decreasing of the critical stress needed to excite dislocation initiation at high temperature. The increasing of true modulus is attributed to the reducing of recoverable indentation depth induced by back-switched domains. The influence of residual stress on the indentation behavior of PZT film composite was also investigated by measuring its load-depth curves with pre-load strains.

No MeSH data available.


Related in: MedlinePlus