1、Designation: E680 79 (Reapproved 2011)1Standard Test Method forDrop Weight Impact Sensitivity of Solid-Phase HazardousMaterials1This standard is issued under the fixed designation E680; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisio
2、n, 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.1NOTEEditorial corrections were made to the format of the Warning notes in August 2011.INTRODUCTIONThis test method
3、 is one of several test methods being developed by ASTM Committee E27 onHazard Potential of Chemicals. This test method is to be used in conjunction with other tests tocharacterize the hazard potential of chemicals.1. Scope1.1 This test method2, 3is designed to determine the relativesensitivities of
4、 solid-phase hazardous materials to drop weightimpact stimulus. For liquid-phase materials refer to TestMethod D2540.1.2 This standard may involve hazardous materials, opera-tions, and equipment. This standard does not purport toaddress all of the safety problems associated with its use. It isthe re
5、sponsibility of whoever uses this standard to consult andestablish appropriate safety and health practices and deter-mine the applicability of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:4D2540 Test Method for Drop-Weight Sensitivity of LiquidMonopropellants53. Summ
6、ary of Test Method3.1 Restrictions are placed upon the ranges of impact toolmasses and striking surface diameters that may be used, and astandard sample thickness is prescribed for all tests.6Inaddition, procedures for sample preparation and treatment, aswell as procedures for detecting reactions th
7、rough the use ofthe human senses, are outlined.3.2 Drop-weight impact tests are to be performed using thewell-known Bruceton up-and-down method.7, 83.3 Outlined is a method for normalizing data generated ondifferent impact apparatus.4. Significance and Use4.1 This test method does not require an ove
8、rall rigidstandardization of the apparatus. Samples are tested eitherunconfined or confined in confinement cups. For confined tests,some of the important cup parameters, such as cup material,cup wall thickness, and fit between the cup and the striking pin,are standardized. Data generated from unconf
9、ined and confinedtests will not, in general, exhibit the same relative scale ofsensitivities, and must be identified as confined or unconfineddata and compared separately.4.2 This test method applies to all testing where the intent isto establish a relative sensitivity scale for hazardous materials.
10、It is not intended to prohibit testing process-thickness samplesnor prohibit the use of other than standard tool masses andstriking diameters to generate data for special purposes or forin-house comparisons. In addition, the test method is not1This test method is under the jurisdiction of ASTM Commi
11、ttee E27 on HazardPotential of Chemicals and is the direct responsibility of Subcommittee E27.02 onThermal Stability and Condensed Phases.Current edition approved Aug. 1, 2011. Published September 2011. Originallyapproved in 1979. Last previous edition approved in 2005 as E680 79 (2005).DOI: 10.1520
12、/E0680-79R11.2This test method is a modification of and contains concepts proposed byHercules, Inc. personnel at Allegheny Ballistics Laboratory. The method wasoutlined by personnel of Pittsburgh Mining and Safety Research Center, Bureau ofMines, Pittsburgh, Pa. For additional information see Footno
13、te 3.3Smith, D., and Richardson, R.H., “Interpretation of Impact Sensitivity TestData,” Pyrodynamics, PYDYA, Vol 6, 1968, pp. 159178.4For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume infor
14、mation, refer to the standards Document Summary page onthe ASTM website.5Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.6Becker, K.R., and Watson, R.W., “A Critique for Drop Weight Impact Testing,”Proceedings of the Conference on the Standardization of
15、Safety and PerformanceTests for Energetic Materials, Vol 1, September 1977, pp. 415 430. PublicationARLCD-SP-77004, U. S. Army Armament Research and Development Command,Dover, N.J.7Dixon, W. J., and Massey, F. J. Jr., Introduction to Statistical Analysis,McGraw-Hill Book Co., Inc., 1957 , pp. 319327
16、.8Statistical Research Group, Princeton University, “Statistical Analysis for aNew Procedure in Sensitivity Experiments,” AMP Report No. 101.1R, SRG-P, No.40, Submitted to Applied Mathematics Panel, National Defense Research Commit-tee, July 1944, p. 58.1Copyright ASTM International, 100 Barr Harbor
17、 Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.intended to restrict the generation of results at other than theH50point as may be desirable for hazard analysis techniques.4.3 The normalized data will serve as a measure of therelative sensitivities of hazardous materials at the
18、50 % prob-ability of reaction level. The normalized H50values can also beused in conjunction with additional data relating to otherprobability of reaction levels (not a part of this test method) toassess hazards associated with the manufacture, transportation,storage, and use of hazardous materials.
19、5. Definitions5.1 H50valuea drop height with a 50 % probability ofreaction, as determined experimentally by the Bruceton up-and-down method.5.2 impact toolsthe drop weight, intermediate weight, andanvil.5.3 drop weightthat weight which is raised to a selectedheight and released. This weight does not
20、 impact the sampledirectly; rather it strikes another stationary weight that is incontact with the sample.5.4 intermediate weightthe stationary weight in contactwith the sample.5.5 anvilthe smooth, hardened surface upon which thetest sample or cup containing the sample rests.5.6 unconfined testa tes
21、t in which the test sample isplaced directly upon the anvil with no lateral confinement.5.7 confined testa test in which the test sample is con-tained within a confinement cup (sample container), and theconfinement cup is then placed upon the anvil.5.8 confinement cupthe metal sample container used
22、inconfined tests.5.9 guide bushingthe steel bushing that surrounds, aligns,and holds the stationary intermediate weight in place.5.10 guide systemthe rails, wires, and shaft that guide thedrop weight during its fall.5.11 striking surfacethe hardened, smooth, circular bot-tom surface of the intermedi
23、ate tool that is in contact with thetest sample.5.12 impact apparatus or machinethe total apparatusincluding the foundation parts, guide rails, electromagnet lift,winch, and tools.6. Apparatus6.1 A complete impact apparatus is the specialized appara-tus necessary for this test method.6.2 The masses
24、of the drop weight (m1) and intermediateweight (m2) should, preferably, be equal. However, the inter-mediate weight mass may be less than that of the drop weightmass so long as the mass ratio m2/m1is 0.6 or greater. Thisensures that the force-time stimulus a test sample is subjectedto will be nonosc
25、illatory in nature, and ensures that the transferof energy from the drop weight to the intermediate weight doesnot vary significantly.6.3 The mass of the drop weight should be between 1.0 to3.5 kg.6.4 The hardness of all tooling surfaces involved in theimpact (drop weight, intermediate weight, and a
26、nvil) shouldhave a Rockwell C Hardness of 55 to 59 HRC.6.5 The diameter of the striking surface of the intermediateweight shall be 9.52 to 19.05 mm (38 to34 in.). These limitswere determined simply on the basis that data have beensuccessfully normalized for tool diameters in this range.6.6 The finis
27、h on the striking surface of the intermediateweight and of the anvil, though not highly critical in tests withsolid explosives, should be a No. 8 grind (8 in.) or finer. Ifsubstantially different surface finishes are used, the dataobtained should be accompanied by a footnote specifying thefinish use
28、d.6.7 In confined tests, the confinement cup shall be fabricatedfrom Type 302 stainless steel. The cup base thickness shallrange from 0.13 to 0.15 mm (0.005 to 0.006 in.). The outerperiphery of the striking pin shall be in contact with a smallportion of the arc joining the side and bottom of the cup
29、.Although this permits greater energy losses in working themetal inside the cup than if the whole striking surface engagedonly the flat portion of the metal in the base of the cup, it doesensure better confinement with less flow of test material up thesides of the striking pin and cup. A typical con
30、finement cup isshown in Fig. 1. This, together with the striking pin dimensionsshown in Fig. 2, provide some insight on a suitable matingbetween the striking pin and cup.6.8 Experience has shown that an appreciable difference inthe behavior of the apparatus can result from the manner inwhich it is m
31、ounted. Thus, the machine should be mounted on,and firmly attached to, a solid concrete foundation, preferablyanchored to the foundation of a building (see Test MethodD2540).6.9 Fig. 3 illustrates a typical impact apparatus, and Figs. 4and 1 are detailed drawings of a drop weight, an intermediatewei
32、ght, and a confinement cup. Helpful notes on constructionof the tools are found in the Appendix. These tools andapparatus are in use at the U. S. Bureau of Mines, Bruceton,Pa., but are not necessarily the only acceptable designs. Alldesigns, however, should incorporate a device that captures thedrop
33、 weight after it rebounds to prevent further interactionswith the intermediate weight.FIG. 1 Confinement Cup Used as a Sample Container in ConfinedTestsE680 79 (2011)127. Test Sample7.1 Sample thickness must be the same for all tests. This isachieved by using a constant volume per unit area samplesp
34、read uniformly over that area. The standard is 31.5 mm3/cm2.This provides a distributed thickness of 0.315 mm (12.4 mils)and ensures the same energy input per unit mass of a given testmaterial no matter what the diameter of the striking surfacearea is. Thus, for a sample diameter of 12.7 mm (0.50 in
35、.),40 mm3of sample volume would be used. Proportionatelylarger or smaller sample volumes, varying in direct proportionto the sample, may be used so long as the sample volume perunit area is 31.5 mm3/cm2. Errors in sample volume may be610 %, and sample measuring spoons having the appropriatevolume ca
36、n be machined or drilled for this purpose. In caseswhere it is desirable to test process thickness samples thatdiffer from the standard, simply indicate the thickness used,especially if the H50values appear in the same tables togetherwith H50values obtained using standard thickness samples.7.1.1 In
37、some cases, the sample consistency may prohibitthe sample from being measured in a measuring spoon. In theseinstances, the proper sample size can be determined by itsmass; M=rV, where V is the proper volume for a given samplearea, andr is the loose-packing density of the sample. Thedensity may have
38、to be determined if it has not been specified.7.2 Specifications of sample diameters to be used in con-junction with different diameter tools are as follows: (a)inconfined tests, specifically, a test where the sample is confinedin a cylindrical cup, the sample diameter will be the same asthe inside
39、diameter of the cup. Hence, calculate a samplevolume or mass based upon the inside diameter of theconfinement cup, and (b) for unconfined tests, specifically, atest where the sample is spread directly upon the anvil, useabout a 0.33-mm (13-mil) thick template made from plastic,metal, or tape having
40、a circular hole cut in it. Place the templateon the anvil, pile the sample in the hole, and scrape level witha spatula or straight edge. The hole diameter should, in allcases, be somewhat larger than the tool contact surfacediameter. Leave the template in place during the impact trial.The larger siz
41、e will make it easy to miss striking the peripheryof the template hole during impact. The template also serves asan excellent means for keeping the sample inbounds. Therecommended template hole for a 12.7-mm (12-in.) diametertool is 15.9 mm (58 in.), but it may be 19.1 mm (34 in.) orlarger, as long
42、as a proportionally larger sample is used. Here,it is important to remember that the sample volume or massused to obtain constant-thickness samples is based upon thetemplate diameter, not the tool diameter.7.2.1 In no case should the sample diameter be less than thatof the tool. The normalization me
43、thod cannot be applied if thisFIG. 2 Intermediate Weight AssemblyFIG. 3 Bureau of Mines Impact ApparatusE680 79 (2011)13is the case. Furthermore, the normalization method cannot beapplied to mixed data from confined and unconfined tests. It isgenerally applicable in the unconfined case. Information
44、islimited on applicability to the confined case. However, it isbelieved that data from confined trials could be normalizedprovided the confinement parameters are reasonably alike. Theimportant cup parameters that were standardized were given in6.7.8. Preparation of Apparatus8.1 Inspection checks of
45、the apparatus are an important partof the test procedure. This includes the physical condition ofcertain parts, alignment, and cleanliness.8.1.1 Physical Condition of Equipment Inspect the guiderails, or wires, or shafts periodically for evidence of nicks,frays, dirt, or other physical impairments,
46、and eliminate anydefects that might impede the drop weight in its fall. Inspectthe drop weight, intermediate weight, and anvil, makingespecially sure that all metal surfaces that are involved in thecollision process are free from defects. Make sure that theintermediate weight slides through and rota
47、tes freely in theguide bushing without significant side play. Recondition orreplace the bottom surface (striking surface) of the intermedi-ate weight or top surface of the anvil if they show any evidenceof wear. Use a new, clean confinement cup each trial inconfined tests if confinement cups (sample
48、 containers) areused.8.1.2 AlignmentAlign the guide system, allowing the dropweight to fall along a path perpendicular to the plane of theearth within 60.25 deg. Misalignments of this magnitude caneasily be detected using a plumb line, since a 0.25-degmisalignment amounts to a 13-mm displacement ove
49、r a3000-mm length.8.1.2.1 Align the bottom face (striking surface) of theintermediate weight and the top surface of the anvil. Thesesurfaces must be both plane and parallel. A convenient way tocheck this is with Prussian blue dye. Place a small amount ofthe dye on a piece of paper and insert the paper between theintermediate tool striking surface and anvil. By hand lower theintermediate tool onto the area of the paper containing the dye.Lift the intermediate tool and insert a clean piece of paper.Lower and raise the tool a number of times on different a
