Journal of Materials Science

, Volume 55, Issue 10, pp 4420–4436 | Cite as

Effect of hydration on mechanical characteristics of pangolin scales

  • Teng Zhou
  • Zhen-bing CaiEmail author
  • Zheng-yang Li
  • Wen YueEmail author
  • Wei Li
  • Jing Zheng
Materials for life sciences


As a typical keratinous material, the mechanical properties of pangolin scales are affected by hydration. Clarifying the mechanism of influence of hydration on dynamic response of materials may provide valuable inspiration for bio-inspired design. In this study, mechanical properties and impact wear behaviors of pangolin scales from different hydrated levels were investigated on a low-velocity impact wear tester. The dynamic response and damage behavior of these pangolin scales were systematically analyzed. Results showed that the energy absorption and impact contact force were considerably distinct with different hydrated levels. The maximum values of the impact contact force are similar to each other in various impact cycles. However, the damage extent of scales was not the same in varied impact cycles. Impact worn scars size of scales increased as the impact cycles increased. Under varied hydrated levels, energy absorption initially decreased and then increased with the increase in moisture content. Specifically, for a hydrated level of 10.5%, the energy absorption had the lowest rate, down to 26.6%, and the impact force decreased. Finally, the mechanisms and factors affecting the dynamic response and impact wear of scales were investigated. This study promoted a bio-inspired design for improving impact wear resistance properties.



This study was supported by the Young Scientific Innovation Team of Science and Technology of Sichuan (No. 2017TD0017), Sichuan province University Scientific Research Innovation Team Project (No. 18TD0005), and Fundamental Research Funds for the central Universities (2018GF01).

Author contributions

ZBC and WY conceived the project. TZ, ZBC, and WY designed and performed the experiments. TZ, WL, and JZ performed sample characterization and data analysis. TZ prepared all the figures and wrote the main manuscript text. All authors contributed to the discussion of the data and reviewed the manuscript.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


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Authors and Affiliations

  1. 1.Tribology Research Institute, Key Lab of Advanced Technologies of MaterialsSouthwest Jiaotong UniversityChengduPeople’s Republic of China
  2. 2.School of Engineering and TechnologyChina University of Geosciences (Beijing)BeijingPeople’s Republic of China

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