ISO 5803:2023

Overview

ISO 5803:2023 specifies a standardized X‑ray powder diffraction (XRD) test method for the qualitative and quantitative determination of the monoclinic phase in zirconia. The method applies to yttria‑stabilized tetragonal zirconia polycrystal (Y‑TZP) powders and monolithic Y‑TZP ceramics with yttria content ≤ 6 mol%. The standard describes sample preparation, recommended XRD instrumentation and scan parameters, calculation of integrated intensity ratios, and conversion to volume/mass fractions using prescribed P values.

Key topics and technical requirements

• Scope: Focus on monoclinic vs tetragonal (and cubic) phase analysis in Y‑TZP (yttria ≤ 6 mol%); guidance for higher stabilizer contents is referenced.
• Principle: Phase identification via XRD; quantitative analysis using the polymorph (integrated‑intensity) method. Full‑pattern/Rietveld methods are recommended for complete multiphase analysis.
• Apparatus & settings:
  • Copper X‑ray tube with monochromator/filter and precise goniometer (2θ error ≤ 0.5°).
  • Suggested excitation ≥ 40 kV and current ≥ 35 mA.
  • Qualitative scan: 2θ = 10°–80°, continuous ≤ 2°/min.
  • Quantitative scan: 2θ = 26.5°–33.5°, step scanning ≤ 0.05°/step.
• Sample preparation:
  • Homogeneous grain size (recommended < 40 µm).
  • Packing per ISO 20203; use backfill pressing to reduce preferred orientation and obtain a flat surface.
• Calculation & P values:
  • Integrated intensity ratio (monoclinic reflections vs tetragonal/cubic) converted to volume fraction using a P intensity factor.
  • For Y‑TZP (yttria ≤ 6 mol%), P = 1.311 is recommended. Annex A lists alternative P values for monoclinic–cubic (mean 1.219) and multiphase systems (1.265).
• Limitations:
  • Results invalid if strong preferred orientation or peak overlap with other phases occurs.
• Reporting: Test reports shall conform to ISO/IEC 17025 and include apparatus, scan parameters, identified ICDD PDF numbers, integrated intensities, P values, and calculated phase fractions.

Applications and users

ISO 5803:2023 is relevant to:

• Quality control and acceptance testing in advanced ceramics manufacturing (Y‑TZP powders and components).
• Materials characterization labs performing XRD phase analysis and quantification.
• R&D teams evaluating phase stability, low‑temperature degradation, or processing effects on zirconia microstructure.
• Suppliers and end‑users needing traceable, comparable monoclinic phase measurements for specification compliance.

Keywords: ISO 5803:2023, monoclinic phase, zirconia, Y‑TZP, X‑ray powder diffraction, XRD, quantitative phase analysis, P value, ceramics testing.

Related standards

• ISO/IEC 17025 (laboratory competence and reporting)
• ISO 20203 (sample packing and crystallite size by XRD)
• CEN ENV 14237 / EVN 14273 (related zirconia phase analysis references)
• Rietveld/full‑pattern XRD methods (for complete multiphase quantification)