ISO 13383-2:2012

Overview

ISO 13383-2:2012 defines a manual, stereological method for determining the phase volume fraction in fine (advanced) ceramics by evaluating micrographs of polished and etched sections. The procedure overlays a transparent square grid on micrographs and counts grid-line intersections over each identifiable phase. It assumes area fractions on a random cross-section are equivalent to true volume fractions and is intended for ceramics containing distinct secondary phases (for example, Al2O3/ZrO2, Si/SiC, Al2O3/SiCw).

Key topics and requirements

• Scope and principle: Use of micrographs and the grid-intersection counting technique to estimate phase volume fractions (stereological basis).
• Sample preparation: Guidance on sampling, sectioning, mounting, grinding, polishing and etching to reveal phases without introducing artefacts (avoid grain pluck‑out).
• Apparatus: Requirements for sectioning equipment, mounting media, diamond-based grinding/polishing, optical or scanning electron microscope (SEM), and a transparent square grid (line thickness ≤ 0.1 mm).
• Microscopy selection:
  • Use SEM when phase grain size or glassy films are < 2 µm.
  • Optical microscopy acceptable for larger features; SEM or optical for 2–4 µm.
• Photomicrography and sampling:
  • At least three micrographs at sufficient magnification.
  • At least 100 features of any given type across the set of images.
  • Ensure representative sampling; survey multiple regions when microstructure is inhomogeneous.
• Counting method: Overlay a square grid and count intersections falling on each phase to compute area/volume fractions.
• Limitations & uncertainties:
  • Porosity treated as a secondary phase if not from polishing damage.
  • Porosity > ~20% risks artefacts during polishing.
  • Phases < ~0.05 (5%) are subject to large error and scatter.
  • Glassy films narrower than 0.5 µm are generally not resolvable by this method.
• Reporting: Document procedure, magnification, number of fields, grid spacing, counts, calculation method and uncertainty.

Applications and users

ISO 13383-2 is used for:

• Quality control and acceptance testing in ceramic component manufacture.
• Materials characterization in research and development.
• Failure analysis and root-cause investigations where phase distribution matters.
• Calibration and inter-laboratory comparisons in metrology and testing labs.

Typical users: materials scientists, ceramic engineers, metallographers, SEM/optical microscopy labs, and accreditation bodies performing quantitative microstructural analysis.

Related standards

• ISO 13383-1 (Microstructural characterization - Part 1: grain size and size distribution)
• ISO/IEC 17025 (laboratory competence)
• Annex A of ISO 13383-2 provides guidance on automatic image analysis (AIA); Annex B discusses round-robin verification.

Keywords: ISO 13383-2, phase volume fraction, microstructural characterization, fine ceramics, micrographs, grid intersection method, polished and etched sections, SEM, optical microscopy, porosity measurement.