6.Test Specimen
6.1Mixing,sheeting,and curing shall be performed in
accordance with Practices D 3182and D 3183,unless other-
wi specified.
6.2The standard test specimen shall have a thickness of
12.560.5mm (0.5060.02in.).The specimen shall be cut so
that the point of plunger impact is a minimum distance of 14迪士尼乐园游玩攻略
mm (0.55in.)from the edge of the specimen.The test
specimen may be molded or cut from a slab.
6.3Alternative specimens may be prepared by plying up
samples cut from a standard test slab.The samples shall be
plied,without cementing,to the thickness required.Such plies
shall be smooth,flat,and of uniform thickness.The results
obtained with the specimens so prepared will not necessarily
be identical with tho obtained using a solid specimen of the
same material and state of cure.
N OTE 5—A thin specimen reaches a higher state of cure at a given time
and temperature of cure than does a thicker specimen.Therefore,if plied-up specimens are ud,their cure time should be appropriately lower than that for a single-piece specimen ud for comparison.6.4Specimens may be prepared from finished products by cutting and buffing to the required dimensions,making sure that the opposing faces are parallel.N OTE 6—If buffing is required,
it is recommended that only one side be buffed and the unbuffed side tested or,if both sides must be buffed,comparisons should not be made between buffed and unbuffed specimens.7.Calibration 7.1Samples of the material being tested are not a valid calibration criteria.7.2A mechanical spring device with a known rebound value must be ud to calibrate this instrument.7.3The instrument may be considered in calibration if the average of five readings taken from the instrument fall within the rebound values of the calibration device.7.4The calibration device values are assigned to the
device
N OTE 1—1in.525.4mm.
FIG.1Rebound
Apparatus
by the manufacturer using a master resilience instrument.
The devices may be verified by the manufacturer as required
by the ur.
N OTE 7—Calibration frequencies and calibration records should be kept
in accordance with procedures outlined in MIL-STD 45662a.
8.Test Temperature
8.1The standard test temperature is 2362°C (73.46
3.6°F).Other temperatures may be specified,preferably chon
from tho given in Practice D 1349.
9.Procedure
9.1If tests are to be made at temperatures lower than 23°C
the specimens should be conditioned in accordance with
Practice D 832and the tests shall be conducted at the condi-
tioning temperature.
9.2Level the instrument and rai the plunger to the top of
its guide rod.
9.3Position the resilience scale so that its full weight rests
upon the specimen.Lock it in this position.
9.4Relea the plunger,making sure that it slides freely on
its guide.
9.5Do not record the first three rebounds.Record the height
of each of the next three rebounds.
9.6Test three specimens.
N OTE 8—Any side pressure or impact on the guide rod may bend it with
a resulting hindrance on the free fall of the plunger.Do not oil any part of
the instrument.Always keep a specimen of rubber under the stabilizer
动作片英语when not in u to avoid damage to the plunger.
10.Calculations
10.1Since the resilience scale is divided into 100parts the
rebound height is equal to the resilience in percent.
11.Report
11.1Report the average resilience recorded from the 4th,
5th,and 6th impacts.
11.2Report the medium of the three specimens.
11.3Report any variation from standard specimen construc-
tion or standard test temperature.
12.Precision and Bias 12.1This precision and bias ction has been prepared in accordance with Pr
actice D 4483.Refer to this practice for terminology and other statistical calculation details.12.2A Type 1(interlaboratory)precision was evaluated in 1987.Both repeatability and reproducibility are short term,a period of a few days parates replicate test results.A test result is the average value,as specified by this test method,obtained on 3determination(s)or measurement(s)of the property or parameter in question.12.3Three different materials were ud in the interlabora-tory program,the were tested in 6laboratories on 2different days.12.4The results of the precision calculations for repeatabil-ity and reproducibility are given in Table 1,in ascending order of material average or level,for each of the materials evalu-ated.12.5The precision of this test method may be expresd in the format of the following statements that u an appropriate value of r ,R ,(r ),or (R ),that is,that value to be ud in decisions about test results (obtained with the test method).The appropriate value is that value of r or R associated with a mean level in the precision table clost to the mean level under consideration at any given time,for any given material in routine testing operations.12.6Repeatability —The repeatability r ,of this test method has been established as the appropriate value tabulated in the precision table.Two single test results,obtained under normal test method procedure,that differ by more than this tabulated r (for any given level)must be considered as derived from different or non-identical sample populations.12.7Reproducibility —The reproducibility R ,of this test method has been established as the appropriate value tabulated in the
precision table.Two single test results obtained in two different laboratories,under normal test method procedures,that differ by more than the tabulated R (for any given level)must be considered to have come from different or non-identical sample populations.12.8Repeatability and reproducibility expresd as a per-centage of the mean level,(r )and (R ),have equivalent application statements as above for r and R .For the (r )and (R )statements,the difference in the two single test results is expresd as a percentage of the arithmetic mean of the two test results.12.9Bias —In test method terminology,bias is the differ-ence between an average test value and the reference (or true)test property value.Reference values do not exist for this test method since the value (of the test property)is exclusively defined by the test method.Bias,therefore,cannot be deter-mined.13.Keywords 13.1impact;rebound;resilience;rubber
TABLE 1Type 1Precision24个字母
N OTE 1—
Sr 5repeatability standard deviation.
怎么判断是长牙哭闹
r 5repeatability.
怎么消除眼袋
(r)5repeatability (on relative basis,%).
S R 5reproducibility standard deviation.
R 5reproducibility.
(R)5reproducibility (on relative basis,%).
Material Average Test Level A Within Laboratories Between
Laboratories
创业园Sr r (r )S R R (R )
RA 37.90.48 1.36 3.58 2.657.5019.8
RE 45.70.53 1.50 3.28 1.41 3.998.73
RF 48.50.59 1.66 3.42 1.37 3.898.02
A Resilience value,scale
reading.
The American Society for Testing and Materials takes no position respecting the validity of any patent rights asrted in connection with any item mentioned in this standard.Urs of this standard are expressly advid that determination of the validity of any such patent rights,and the risk of infringement of such rights,are entirely their own responsibility.竹笋怎么炒好吃
服装造型
This standard is subject to revision at any time by the responsible technical committee and must be reviewed everyfive years and if not revid,either reapproved or withdrawn.Your comments are invited either for revision of this standard or for additional standards and should be addresd to ASTM Headquarters.Your comments will receive careful consideration at a meeting of the responsible technical committee,which you may attend.If you feel that your comments have not received a fair hearing you should make your views known to the ASTM Committee on Standards,100Barr Harbor Drive,West Conshohocken,PA19428.
