prDS CEN ISO/TR 20659-1:2024

Metodat e provës reologjike - Bazat dhe krahasimet ndërlaboratorike - Pjesa 1: Përcaktimi i pikës së rendimentit (ISO/TR 20659-1:2024)

Rheological test methods - Fundamentals and interlaboratory comparisons - Part 1: Determination of the yield point (ISO/TR 20659-1:2024)

Scope

This document gives information on an interlaboratory comparison for the determination of the yield point, using rheological test methods. The yield point is the shear stress τ below which a material does not flow.
This document provides examples of fields of applications, in which important material properties are characterized with the aid of the yield point. These fields of application include:
—    effectiveness of rheological additives;
—    shelf life (e.g. with regard to sedimentation, separation and flocculation);
—    stability of the structure at rest;
—    behaviour when starting to pump;
—    use in scraper systems;
—    wet-film thickness;
—    levelling and sagging behaviour (e.g. without brushmarks or sag formation);
—    orientation of effect pigments.