Non-destructive microstructural analysis with depth resolution: application to seashells

• Published in: Journal of applied crystallography Vol. 35; no. 5; pp. 594 - 599
• Main Authors: Zolotoyabko, E., Quintana, J. P.
• Format: Journal Article
• Language: English
• Published: 5 Abbey Square, Chester, Cheshire CH1 2HU, England Munksgaard International Publishers 01.10.2002; Blackwell
• Subjects: Biological and medical sciences; Crystalline structure; depth-dependent microstructure; energy-variable X-ray diffraction; Fundamental and applied biological sciences. Psychology; lamella structure; line profile analysis; microstrain; Molecular biophysics; polycrystalline materials; Structure in molecular biology; Shell; Depth resolution; Microstructure; Crystallography; Analysis
• ISSN: 1600-5767; 0021-8898; 1600-5767
• DOI: 10.1107/S0021889802011160

Energy‐variable X‐ray diffraction at a synchrotron beamline has been used to control the X‐ray penetration depth and thus to study structural parameters in polycrystalline and textured materials with depth resolution. This approach was applied to the investigation of the depth evolution of microstructure in the nacre layer of bivalvia seashells. According to conventional X‐ray diffraction and scanning electron microscopy, the nacre layer in the seashells of Acanthocardia tuberculata under investigation consists of large [001]‐oriented lamellae packed nearly parallel to the inner shell surface. In this paper, attention is focused on the microstructural information that can be extracted from the shapes of diffraction profiles (line profile analysis) measured at X‐ray energies that are varied by small steps. Depth dependences of the thickness of the lamellae and the average microstrain fluctuation are revealed.