Overview
EN 23312:1993 (identical to ISO 3312:1987) specifies a standardized method to determine the dynamic (adiabatic) Young modulus of sintered metal materials and hardmetals by exciting longitudinal ultrasonic oscillations and measuring the specimen’s resonance frequency. Published by CEN and prepared by ISO/TC 119 (Powder Metallurgy), this edition replaces the earlier 1975 version and defines principle, apparatus, specimen preparation, procedure, result expression and required test report information.
Key Topics and Requirements
- Test principle: excite longitudinal oscillations in a fixed specimen and measure the natural resonance frequency.
- Apparatus:
- Fixture to mount the specimen
- Ultrasonic oscillator with continuous control in the 20–100 kHz range
- Device for determining resonance frequency (resolution to ±50 Hz)
- Specimen dimensions:
- Minimum length: 60 mm
- Round cross-section: 6 +0.2 mm diameter
- Rectangular cross-section: (6 +0.2) mm × (8 +0.2) mm
- Surface and dimensional tolerances:
- Remove surface layer ≥ 0.1 mm
- Surface roughness Ra ≤ 1.25 µm
- End faces ground and parallel within 0.02 mm
- Specimen free of surface cracks and cleaned immediately before testing
- Density and length measurements:
- Density determined per ISO 2738 to 0.01 g/cm³
- Length measured to 0.1 mm
- Calculation:
- Young modulus given by: E = 4 × 10^−9 × L^2 × ρ × f^2 (as in the standard)
- Report results rounded to the nearest 5 × 10^3 N/mm²
- Test report must reference the standard, identify the sample, state the result and any non‑specified operations or events affecting results.
Applications and Who Uses It
- Practical for quality control, R&D and materials characterization in:
- Powder metallurgy manufacturers
- Hardmetal (cemented carbide) producers
- Materials testing laboratories and certification bodies
- Design engineers needing elastic property data for components made from sintered metals
- Useful for comparing mechanical stiffness (Young modulus) between sintered compositions, porosity levels and processing routes.
Related Standards
- ISO 2738 - Determination of density, oil content and open porosity for permeable sintered metal materials (referenced for density measurement).
- Note: EN 23312:1993 corresponds to ISO 3312:1987; earlier edition ISO 3312:1975 was cancelled.
Keywords: EN 23312:1993, ISO 3312:1987, Young modulus, sintered metal materials, hardmetals, dynamic Young’s modulus, longitudinal oscillations, resonance frequency, powder metallurgy, mechanical testing.
