ISO 20379:2018 PDF

Fine ceramics (advanced ceramics, advanced technical ceramics) — Measurement of thixotropic behaviour of ceramic slurry by use of a rotational viscometer

Open preview (PDF)

Title (English):

ISO 20379:2018

Fine ceramics (advanced ceramics, advanced technical ceramics) — Measurement of thixotropic behaviour of ceramic slurry by use of a rotational viscometer

Document status:: Active
Format:: Electronic (PDF)
Number of pages:: 8
Publication date:: February 13, 2018
Edition:: ISO IS 20379 edition 1 version 1
ICS:: 81.060.30

Delivery type:

Full version25 €Read online 24h10 €Read online 72h15 €

Document language:

enru

Delivery time:Immediate download

Price:25 €

Description (English):

ISO 20379:2018 specifies a method for measurement of thixotropic behaviour of ceramic slurry with rotational viscometer. The slurry with high-solid loading, which is used in ceramic manufacturing, has a generally non-Newtonian property. This method is limited to measurement of thixotropic behaviour of high-solid loaded ceramic slurry with "coaxial double cylinder viscometer", "cone and plate viscometer" and "a parallel plate viscometer" as rotational viscometers.

Technical details

Technical committee: ISO/TC 206 - Fine ceramics
SKU: ISO 20379:2018

Abstract

Overview

ISO 20379:2018 specifies a standardized method to measure the thixotropic behaviour of high-solid loaded ceramic slurry using a rotational viscometer. Targeted at fine ceramics (advanced/technical ceramics) manufacturing, the standard covers measurement principles, apparatus requirements, sample pretreatment, measurement procedures and analysis methods for evaluating time-dependent viscosity changes in non-Newtonian ceramic slurries.

Key search keywords: ISO 20379:2018, thixotropic behaviour, ceramic slurry, rotational viscometer, fine ceramics, viscosity measurement.

Key topics and technical requirements

Scope and limitations
- Applies to high-solid loading ceramic slurries used in ceramic processes (e.g., slip casting, tape casting, screen printing).
- Measurement geometries limited to: coaxial double cylinder, cone-and-plate, and parallel plate rotational viscometers.
Measurement principles
- Two evaluation approaches:
  - Hysteresis measurement of the flow curve (shear-rate sweep up/down to quantify hysteresis area).
  - Time-dependence of shear stress at constant low shear rate (monitor recovery after high-shear disruption).
Apparatus and performance
- Viscometer must permit defined shear-rate generation and torque measurement.
- Recommended instrument accuracy: torque within ±2% of full-scale, rotational frequency within ±2%, repeatability ±2%.
- Periodic calibration using standard viscosity solutions; calibration temperature must match measurement temperature.
Sample preparation and measurement conditions
- Avoid bubble generation when loading slurry; degassing by decompression must be reported if used.
- Avoid heating by high-speed dispersion (stirring/ultrasonication) which can alter dispersants/binders.
- Preferred measurement temperature 23 ± 0.2 °C; thermostat control accuracy recommended within ±0.2 °C.
- Example procedural recommendations: maximum shear rate ~300 s⁻¹ (where practical), ~90 s for shear-rate increase and decrease, rest 3–5 min, repeat measurements at least three times.
Analysis
- Hysteresis quantified dimensionlessly as (A − B)/(A + B), where A and B are areas under increasing and decreasing flow curves.
- Time-dependent recovery analyzed from shear-stress vs time at low shear rate.

Applications and users

Practical uses:
- Characterizing slurry behavior for casting, coating, tape casting, screen printing, granulation and other ceramic forming processes.
- Quality control, formulation optimization and process troubleshooting where time-dependent viscosity (thixotropy) affects coating uniformity, sedimentation, or forming performance.
Primary users:
- Materials scientists, ceramic process engineers, R&D labs, QC laboratories in ceramics and electronic-ceramic manufacturing, and instrument manufacturers.

Related information

ISO 20379:2018 contains no normative references. For broader rheology and calibration practices, consult general standards and guidelines on viscometer calibration and rheological testing from national or international bodies.

Related standards

Other ISO standards

Abstract

Overview

Key search keywords: ISO 20379:2018, thixotropic behaviour, ceramic slurry, rotational viscometer, fine ceramics, viscosity measurement.

Key topics and technical requirements

Scope and limitations
- Applies to high-solid loading ceramic slurries used in ceramic processes (e.g., slip casting, tape casting, screen printing).
- Measurement geometries limited to: coaxial double cylinder, cone-and-plate, and parallel plate rotational viscometers.
Measurement principles
- Two evaluation approaches:
  - Hysteresis measurement of the flow curve (shear-rate sweep up/down to quantify hysteresis area).
  - Time-dependence of shear stress at constant low shear rate (monitor recovery after high-shear disruption).
Apparatus and performance
- Viscometer must permit defined shear-rate generation and torque measurement.
- Recommended instrument accuracy: torque within ±2% of full-scale, rotational frequency within ±2%, repeatability ±2%.
- Periodic calibration using standard viscosity solutions; calibration temperature must match measurement temperature.
Sample preparation and measurement conditions
- Avoid bubble generation when loading slurry; degassing by decompression must be reported if used.
- Avoid heating by high-speed dispersion (stirring/ultrasonication) which can alter dispersants/binders.
- Preferred measurement temperature 23 ± 0.2 °C; thermostat control accuracy recommended within ±0.2 °C.
- Example procedural recommendations: maximum shear rate ~300 s⁻¹ (where practical), ~90 s for shear-rate increase and decrease, rest 3–5 min, repeat measurements at least three times.
Analysis
- Hysteresis quantified dimensionlessly as (A − B)/(A + B), where A and B are areas under increasing and decreasing flow curves.
- Time-dependent recovery analyzed from shear-stress vs time at low shear rate.

Applications and users

Practical uses:
- Characterizing slurry behavior for casting, coating, tape casting, screen printing, granulation and other ceramic forming processes.
- Quality control, formulation optimization and process troubleshooting where time-dependent viscosity (thixotropy) affects coating uniformity, sedimentation, or forming performance.
Primary users:
- Materials scientists, ceramic process engineers, R&D labs, QC laboratories in ceramics and electronic-ceramic manufacturing, and instrument manufacturers.

Related information

ISO 20379:2018 contains no normative references. For broader rheology and calibration practices, consult general standards and guidelines on viscometer calibration and rheological testing from national or international bodies.

ISO 20379:2018 PDF

Technical details

Abstract

Overview

Key topics and technical requirements

Applications and users

Related information

Related standards

Abstract

Overview

Key topics and technical requirements

Applications and users

Related information

Related standards

Systems and software engineering — Software life cycle processes

Asset management — Vocabulary, overview and principles

Asset management — Asset management system — Requirements

Information technology — Radio frequency identification device conformance test methods — Part 2: Test method…

Information technology — Multimedia framework (MPEG-21) — Part 22: User Description

Milk — Determination of the lactoperoxidase activity — Photometric method (Reference method)

Carbonaceous materials for the production of aluminium — Cold and tepid ramming pastes — Expansion/shrinkage…

Agricultural machinery — Safety — Part 13: Large rotary mowers