1、Designation: D 1790 02Standard Test Method forBrittleness Temperature of Plastic Sheeting by Impact1This standard is issued under the fixed designation D 1790; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisi
2、on. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 This test method covers the determination of t
3、hattemperature at which plastic sheeting 1.00 mm (0.040 in.) orless in thickness exhibits a brittle failure under specified impactconditions.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.NOTE 1This test method was develop
4、ed jointly with the Society ofthe Plastics Industry, primarily for use with plasticized vinyl sheetings. Itsapplicability to other plastic sheetings must be verified by the user.1.3 This standard does not purport to address the safetyconcerns, if any, associated with its use. It is the responsibilit
5、yof the user of this standard to establish appropriate safety andhealth practices and determine the applicability of regulatorylimitations prior to use. Specific precautionary statements aregiven in Note 4.NOTE 2This test method is similar to ISO 8570-1991 in title only. Thetechnical content is sign
6、ificantly different.2. Referenced Documents2.1 ASTM Standards:D 618 Practice for Conditioning Plastics for Testing2D 883 Terminology Relating to Plastics2E 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method32.2 ISO Standard:ISO 8570-1991 PlasticsFilm and
7、SheetingDetermination of Cold-Crack Temperature43. Terminology3.1 Definitions:3.1.1 brittleness temperature, Tbthat temperature, de-rived statistically, where 80 % of the specimens would prob-ably pass 95 % of the time when a stated minimum number aretested by this test method. The 80 %-passing valu
8、e may bedetermined by plotting the data on probability graph paper, asdescribed in 9.1.3.1.2 GeneralDefinitions of terms applying to this testmethod appear in Terminology D 883.4. Significance and Use4.1 Data obtained by this test method may be used to predictthe behavior of plastic sheeting at low
9、temperatures only if theconditions of deformation are similar to those specified in thistest method. This test method is useful for specification testingand for comparative purposes, but does not necessarily mea-sure the lowest temperature at which the plastic sheeting maybe used.4.2 It has been dem
10、onstrated that on calendered sheeting thebrittleness temperature is sensitive to the direction of fold. Ithas also been demonstrated that the brittleness temperature issensitive to the direction of sampling. Therefore, it is impera-tive that the procedure for taking specimens and folding befollowed
11、explicitly.5. Apparatus5.1 Cold Conditioning Chamber, at least 450 by 450 by 450mm (18 by 18 by 18 in.). Means (automatic or manual) shall beprovided for controlling the temperature of the chamber towithin 62C of the desired value.5.2 Impact Tester5shown in Fig. 1 shall be constructed ofcold-rolled
12、steel except for the bolts, screws, and rubberstopper. All structural parts (that is, base, anvil, arm, armsupports, and shaft) may be chromium plated. The arm,including the rubber stopper and bolt, shall weigh 3.09 kg 6 28g(6lb136 1 oz).5.3 Die, 50.8 6 0.4 mm by 146.1 6 0.4 mm (2 6164 in. by534 616
13、4 in.) to cut the test specimens from the sample.5.4 Stapler, desk-type, with a stop mounted on the baseexactly 12.7 mm (12 in.) back of the center of the groover thatturns the staple.5.5 Index Card Stock, 50 by 127 mm (2 by 5 in.).1This test method is under the jurisdiction of ASTM Committee D20 on
14、 Plasticsand is the direct responsibility of Subcommittee D20.30 on Thermal Properties.Current edition approved March 10, 2002. Published May 2002. Originallypublished as D 1790 60 T. Last previous edition D 1790 99.2Annual Book of ASTM Standards, Vol 08.01.3Annual Book of ASTM Standards, Vol 14.02.
15、4Available from American National Standards Institute, 25 W. 43rd St., 4thFloor, New York, NY 10036.5A suitable tester is available from the United States Testing Co., 1415 ParkAve., Hoboken, NJ.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr
16、 Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6. Test Specimens6.1 The test specimens shall be cut with the die. The lengthof the test specimen shall be parallel to the transverse directionof the sheeting. The 50-mm (2-in.) ends of each specimen shallbe so collected tha
17、t a gradual, closed loop is formed at roomtemperatures. The collected ends of the specimen and one endof the 50 by 127-mm (2 by 5-in.) card shall be matched exactlywith the body of the loop lying on the card. Two staples shallbe crimped through the matched ends of the specimen andcard. These staples
18、 shall be 13 mm (12 in.) from, and parallelto, the 50-mm (2-in.) end of the stack.6.2 Since it has been demonstrated that this test is sensitiveto the direction of fold on calendered sheeting, it is necessaryto stipulate that all specimens be folded in the same direction.It is recommended that, for
19、materials with no grain, thespecimen be folded so that the surface last in contact with theroll shall be inside the loop following the inherent shape of thespecimen; grained materials are to be tested with the grainedsurface on the inside of the loop.7. Conditioning7.1 ConditioningCondition the test
20、 specimens at 23 62C (73.4 6 3.6F) and 50 6 5 % relative humidity for not lessthan 40 h prior to test in accordance with Procedure A ofPractice D 618, for those tests where conditioning is required.In cases of disagreement, the tolerances shall be 61C(61.8F) and 62 % relative humidity.7.2 Test Condi
21、tionsConduct tests in the standard labora-tory environment of 23 6 2C (73.4 6 3.6F) and 50 6 5%relative humidity, unless otherwise specified in the test meth-ods or in this test method. In cases of disagreements, thetolerances shall be 61C (61.8F) and 62 % relative humid-ity.8. Procedure8.1 Place th
22、e impact tester, with its base horizontal, in thecold conditioning chamber at the desired testing temperature,for a conditioning period of 1 h. Expose the specimens to thetest temperature for 15 6 5 min.8.2 Place each of ten mounted test specimens individuallyon the anvil with the crimped ends of th
23、e staples on the backof the card fitted into the groove in the anvil. Handle the card,not the sample. Locate the bent loop of the sheeting on theanvil with the loop centered on the anvil and facing away fromthe pivotal end of the impact arm.8.3 Allow the impact arm to fall free from a position withi
24、n5 perpendicular to the base onto the bent loop. Repeat untileach of the ten conditioned specimens has been tested.8.4 Remove the specimens and examine for failure. Partialfracture shall be construed as failure as well as completedivision into two or more pieces.8.5 Adjust the temperature of the col
25、d conditioning chamberand condition a second group of ten specimens for 15 6 5 minat a suitable temperature, as indicated by the results of testingthe first group of ten specimens. Repeat the testing procedureand examination.8.6 When using the standard graphic method to determinethe 80 %-passing tem
26、perature, it is necessary to repeat thisprocedure of testing ten specimens at a series of temperaturesdiffering by uniform increments of 5C. When using theprobability graph paper in 9.1, it is not necessary to obtain thelowest no-failure temperatures, at which no failure is obtained,or the highest f
27、ailure temperature.8.7 When testing for conformance to a specification, it shallbe satisfactory to accept materials on the basis of testing aminimum of ten test specimens at the specified temperature.Not more than 20 % of the specified number of test specimensshall fail at the specified temperature.
28、9. Calculation9.1 Graphic MethodPlot the data on probability graphpaper with the temperature on the linear scale and the percent-age failure on the probability scale. Select the temperaturescale so that it represents a minimum of two divisions perMetric Equivalentsin.mm183.2146.471611.11212.7125.421
29、2643764121141230514356FIG. 1 Brittleness Temperature Impact Testing MachineD1790022degree Celsius. Draw a straight line through a minimum of fourpoints, two above and two below the 50 % point. The tempera-ture indicated at the intersection of the data line with the 20 %failure line shall be reported
30、 as Tb, the 80 % passing tempera-ture (20 % failure temperature).10. Report10.1 Report the following information:10.1.1 Complete identification of the material tested, includ-ing type, source, manufacturers code designation, form, andprevious history,10.1.2 Eighty percent passing temperature, to the
31、 nearestdegree Celsius,10.1.3 Thickness of test specimen,10.1.4 Direction of fold,10.1.5 Conditioning procedure, and10.1.6 Date of test.10.2 For routine acceptance testing, report the followinginstead of 10.1.1, and 10.1.2:10.2.1 Number of specimens tested,10.2.2 Temperature of test, and10.2.3 Numbe
32、r of failures.11. Precision and Bias11.1 Table 1 is based on a round robin conducted in 1991 inaccordance with Practice E 691, involving three materialstested by seven laboratories. For each material, all of thesamples were prepared at one source, but the individualspecimens were prepared at the lab
33、oratories that tested them.The test result for each material was based on a minimum offour trials, performed under varying conditions, involving tenspecimens in each trial. Each laboratory obtained two testresults for each material.NOTE 3Material Number 3 (SP-61737 Lot 30) was tested success-fully b
34、y only three of the seven participating labs due to equipmentlimitations.NOTE 4Caution: The following explanations of r and R (11.2 through11.2.3) are only intended to present a meaningful way of considering theapproximate precision of this method. The data in Table 1 should not berigorously applied
35、 to acceptance or rejection of material, as those data arespecific to the round robin and may not be representative of other lots,conditions, materials, or laboratories. Users of this test method shouldapply the principles outlined in Practice E 691 to generate data specific totheir laboratory and m
36、aterials, or between specific laboratories. Theprinciples of 11.2 through 11.2.3 would then be valid for such data.11.2 Concept of r and RIf Srand Sthave been calculatedfrom a large enough body of data, and for test results that wereaverages from testing 40 specimens (four trials involving tenspecim
37、ens in each trial):11.2.1 Repeatability Limit, r(Comparing two test resultsfor the same material, obtained by the same operator using thesame equipment on the same day.) The two test results shouldbe judged not equivalent if they differ by more than the “r”value for that material.11.2.2 Reproducibil
38、ity Limit, R(Comparing two test re-sults for the same material, obtained by two different operatorsusing different equipment in different laboratories.) The twotest results should be judged not equivalent if they differ bymore than the “R” value for that material.11.2.3 Any judgment in accordance wi
39、th 11.2.1 or 11.2.2would have an approximate 95 % probably of being correct.11.3 There are no recognized standards by which to estimatethe bias of this test method.12. Keywords12.1 brittleness temperature; cold-crack temperature; im-pact; plastic sheetingSUMMARY OF CHANGESThis section identifies the
40、 location of selected changes to this test method. For the convenience of the user,Committee D20 has highlighted those changes that may impact the use of this test method. This section may alsoinclude descriptions of the changes or reasons for the changes, or both.D 179002:(1) Revised 5.1.D 179099:(
41、1) Included a Summary of Changes section.D 179094e1:(1) Footnote 5 and 10.1.2 were corrected editorially in August1995.D 179094:(1) The definition of brittleness temperature in 3.1.1 wasrevised, an ISO equivalency statement was added, and theprecision and bias was updated.TABLE 1 Statistical Assessm
42、ent of Brittleness TemperatureRound-Robin ResultsValues Expressed in CNumber Material Description Average SrASRBrCRD1 HN-81414 Lot 3Squirrel Grey0.013 in.(0.33 mm)16.2 0.62 2.36 1.74 6.612 HC-41310 Lot 2Special Tan0.014 in.(0.36 mm)18.3 0.80 2.88 2.24 8.103 SP-61737 Lot 30Blue0.020 in.(0.51 mm)39.2
43、0.73 3.71 2.04 10.4ASr= within-laboratory standard deviation.BSR= between-laboratory standard deviation.Cr = within-laboratory repeatability limit = 2.8*Sr.DR = between-laboratory reproducibility limit = 2.8*SR.D1790023ASTM International takes no position respecting the validity of any patent rights
44、 asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any ti
45、me by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will
46、receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM
47、International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D1790024
