ASTM D2884-93(2012)

1.1 This test method covers determination of the yield stress of heterogeneous propellants, both of the gel and emulsion types, containing from 0 to 70 % solid additives.

1.2 The values stated in SI units are to be regarded as the standard. In cases where materials, products, or equipment are available in inch-pound units only, SI units are omitted.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
Significance and Use:

The yield stress is a measure of the forces required to initiate and maintain flow from a storage vessel. If all the factors are constant, the propellant with the lower yield stress can be removed more completely from the vessel.