ISO 19618:2025 pdf download,Fine ceramics (advanced ceramics, advanced technical ceramics) — Measurement method for normal spectral emissivity using blackbody reference with an FTIR spectrometer.
ISO 19618:2025 defines a method for measuring the normal spectral emissivity and normal quasi-total emissivity of advanced ceramics. The measurement utilizes a blackbody reference source and a Fourier transform infrared spectrometer (FTIR) at high temperatures. This method applies to fine ceramics, ceramic matrix composites, and continuous fiber-reinforced ceramic matrix composites that are opaque and exhibit low reflectivity in the wavelength range of 1.67 μm to 25 μm. The applicable temperature range is from approximately 350 K to 1100 K.