1、Designation:D288493(Reapproved 2012)Standard Test Method forYield Stress of Heterogeneous Propellants by ConePenetration Method1This standard is issued under the fixed designation D2884;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision
2、,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method2,3covers determination of the yieldstress of heterogeneous propellants,both of the gel andemu
3、lsion types,containing from 0 to 70%solid additives.1.2 The values stated in SI units are to be regarded as thestandard.In cases where materials,products,or equipment areavailable in inch-pound units only,SI units are omitted.1.3 This standard does not purport to address all of thesafety concerns,if
4、 any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:4D2507 Terminology of Rheological Properties of Gel
5、ledRocket Propellants(Withdrawn 2003)53.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 penetration of a propellant,nThe depth,in tenths ofa millimetre that a standard cone penetrates the sample underprescribed conditions of weight,time,and temperature.3.1.2 unworked penetration,
6、nthe penetration at 298 K(77F)of a sample of the propellant which has received onlythe minimum disturbance in transfer from the sample can to agrease worker cup or dimensionally equivalent container.Thisshall be 76.2 6 0.3 mm(3 6 0.01 in.)in inside diameter and63.56 1.6 mm(2.5 6 0.06 in.)deep,as sho
7、wn in Fig.1.3.1.2.1 DiscussionThe conversion of penetration to yieldstress has not been corrected for the displacement of the sampleby the submerged portion of the cone.For this reason cupdiameter is critical,and any deviation from 76.2 6 0.3 mm(36 0.01 in.)must be reported as a nonstandard conditio
8、n.3.1.3 yield stressthe maximum shear stress that can beapplied without causing permanent deformation(see Terminol-ogy D2507).Specifically in this test method,it is the weight ofthe 30-g mass cone-test rod assembly in dynes,corrected forbuoyancy,divided by the calculated wetted area of the cone(that
9、 is,the area of the cone in contact with the propellant afterthe 5-s drop period).4.Summary of Test Method4.1 The penetration is determined at 298 K(77F)byreleasing the cone-test rod assembly from the penetrometer andallowing the assembly to drop for 5 s.The cone will beessentially at rest in less t
10、han this time,so that exact timing isnot critical.5.Significance and Use5.1 The yield stress is a measure of the forces required toinitiate and maintain flow from a storage vessel.If all thefactors are constant,the propellant with the lower yield stresscan be removed more completely from the vessel.
11、6.Apparatus6.1 Penetrometer,to measure the penetration of the standardcone in the propellant.The cone assembly or the table of thepenetrometer shall be adjustable to enable accurate placementof the cone on the level surface of the propellant whilemaintaining a zero reading on the indicator.The cone
12、shouldfall,when released,without appreciable friction for at least42.0 mm but not more than 60.0 mm so the cone will not hit thebottom of the container.The instrument shall be provided withleveling screws to maintain the cone shaft in a vertical positionand a spirit level to determine the attitude o
13、f the instrument.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.L0.07 on Engineering Sciences of High Performance Fluids andSolids(Formally D02.1100).Current edition approved April
14、 15,2012.Published April 2012.Originallyapproved in 1970.Last previous edition approved in 2007 as D288493(2007).DOI:10.1520/D2884-93R12.2This test method is identical in substance with the JANNAF method,“Hetero-geneous Propellant Characterization,Part III,Procedure for Measuring Yield Stressof Hete
15、rogeneous Propellants,”published by the Chemical Propulsion InformationAgency,July 1969,Johns Hopkins University,Applied Physics Laboratory,JohnsHopkins Rd.,Laurel,MD 20810.3ASTM Committee F07 on Aerospace and Aircraft maintains a continuedinterest in this test method and will make use of it in the
16、future.4For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.5The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.1.1 A 15-g test rod shall be substituted for the regular47.5-g
