J4 ›› 2009, Vol. 6 ›› Issue (3): 203-213.doi: 10.1016/S1672-6529(08)60125-0

• 论文 •    下一篇

Sea Urchin Spines as a Model-System for Permeable, Light-Weight Ceramics with Graceful Failure Behavior. Part I. Mechanical Behavior of Sea Urchin Spines under Compression

V. Presser, S. Schultheiß, C. Berthold, K. G. Nickel   

  1. Institute for Geosciences, Eberhard-Karls-Universität Tübingen, D-72074 Tübingen, Germany
  • 出版日期:2009-09-30
  • 通讯作者: V. Presser E-mail:volker.presser@uni-tuebingen.de

Sea Urchin Spines as a Model-System for Permeable, Light-Weight Ceramics with Graceful Failure Behavior. Part I. Mechanical Behavior of Sea Urchin Spines under Compression

V. Presser, S. Schultheiß, C. Berthold, K. G. Nickel   

  1. Institute for Geosciences, Eberhard-Karls-Universität Tübingen, D-72074 Tübingen, Germany
  • Online:2009-09-30
  • Contact: V. Presser E-mail:volker.presser@uni-tuebingen.de

摘要:

The spines of pencil and lance urchins Heterocentrotus mammillatus and Phyllacanthus imperialis were studied as a model of light-weight material with high impact resistance. The complex and variable skeleton construction (“stereom”) of body and spines of sea urchins consists of highly porous Mg-bearing calcium carbonate. This basically brittle material with pronounced single-crystal cleavage does not fracture by spontaneous catastrophic device failure but by graceful failure over the range of tens of millimeter of bulk compression instead. This was observed in bulk compression tests and blunt indentation experiments on regular, infiltrated and latex coated sea urchin spine segments. Microstructural characterization was carried out using X-ray computer tomography, optical and scanning electron microscopy. The behavior is interpreted to result from the hierarchic structure of sea urchin spines from the macroscale down to the nanoscale. Guidelines derived from this study see ceramics with layered porosity as a possible biomimetic construction for appropriate applications.

关键词: sea urchin spines, biomimetic, mechanical behavior, compression, calcite

Abstract:

The spines of pencil and lance urchins Heterocentrotus mammillatus and Phyllacanthus imperialis were studied as a model of light-weight material with high impact resistance. The complex and variable skeleton construction (“stereom”) of body and spines of sea urchins consists of highly porous Mg-bearing calcium carbonate. This basically brittle material with pronounced single-crystal cleavage does not fracture by spontaneous catastrophic device failure but by graceful failure over the range of tens of millimeter of bulk compression instead. This was observed in bulk compression tests and blunt indentation experiments on regular, infiltrated and latex coated sea urchin spine segments. Microstructural characterization was carried out using X-ray computer tomography, optical and scanning electron microscopy. The behavior is interpreted to result from the hierarchic structure of sea urchin spines from the macroscale down to the nanoscale. Guidelines derived from this study see ceramics with layered porosity as a possible biomimetic construction for appropriate applications.

Key words: sea urchin spines, biomimetic, mechanical behavior, compression, calcite