BS ISO 19613:2018 pdf download

BS ISO 19613:2018 pdf download.Fine ceramics (advanced ceramics, advanced technical ceramics) — Measurement of viscosity of ceramic slurry by use of a rotational viscometer
1 Scope
This document specifies a method for measurement of the viscosity of a ceramic slurry using a rotational viscometer.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories
ISO 20507, Fine ceramics (advanced ceramics, advanced technical ceramics) — Vocabulary
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 20507 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at http://www.electropedia.org/
3.1 shear stress
stress acting on planes parallel to the direction of flow when the fluid is subject to laminar flow
Note 1 to entry: The SI units are pascals (Pa).
3.2 shear rate
gradient of laminar flow rate perpendicular to the fluid flow
Note 1 to entry: The SI units are s −1 .
3.3 viscosity
ratio of shear stress to shear rate
Note 1 to entry: This ratio is representative of the internal resistance of the fluid to flow.
Note 2 to entry: The SI unit of viscosity is Pa × s.
Note 3 to entry: mPa × s = 1 cP in terms of c.g.s. units [where 1 P = 1 g/(cm × s)].
Note 4 to entry: Viscosity is sometimes called ‘dynamic viscosity’ or ‘shear viscosity’ for clarification. The measured viscosity is conventionally called ‘apparent viscosity’ since the gradient of shear rate is not identical for all parts of the spindle.
5.2 Rotational viscometer with defined shear rate.
5.2.1 Measuring system
The measuring system shall consist of two rigid, symmetrical, coaxial surfaces between which the fluid whose viscosity is to be measured is placed. One of these surfaces shall rotate while the other remains at rest. The measuring system shall be such that the shear rate can be defined for each measurement. A torque-measuring device shall be connected to one of the surfaces, thus permitting determination of the torque required to overcome the viscous resistance of the fluid. Suitable measuring systems are the coaxial double cylinder system (Annex A), cone and plate system (Annex B), and parallel plate system (Annex C), as prescribed by JIS 8803 and ISO 20507. The dimensions of each measuring system are detailed in Annexes A, B, and C, which are designed to ensure a geometrically similar flow field for all types of measurement and all common types of basic instrument.