1、fi-69-03 ASTM F I 1 2 8 48 m 0757510 0050010 O M H-K G -.rq AMERICAN SOCIETY FOR TESTING AND MATERIALS 1916 Race St.,Philadelphia,Pa.19103 Reprinted from the Annual Book of ASTM Standards,Copyright ASTM if not listed in the currant combined index,wiii appear in lhe next edllion.Tb Designation:F 1128
2、-88 Standard Test Method for Abrasion Resistance of Transparent Plastics and Coatings Using Salt Impingement Method This standard is issued under the fixed designation F 1128;the number immediately following the designation indicates the year of onginal adoption or,in the case of revision,the year o
3、f last revision.A number in parentheses indicates the year of last reapproval.A superscript epsilon(e)indicates an editorial change since the last revision or reapproval.1.Scope I.1 This test method determines the resistance of trans-parent plastics and transparent coatings,utilized in wind-shields,
4、windows,or viewing ports,to surface abrasion using the impingement of salt driven by air blasts.I.2 This standard may involve hazardous materials,oper-ations,and equipment.This standard does not purport to address all o f the safety problems associated with its use.It is the responsibility o f the u
5、ser o f this standard to establish appropriate safety and health practices and determine the applicability o f regulatory limitations prior to use.2.Referenced Documents 2.1 ASTM Standards:C 136 Method for Sieve Analysis of Fine and Coarse D 6 18 Method of Conditioning Plastics and Electrical D 1003
6、 Test Method for Haze and Luminous Transmit-D 1044 Test Method for Resistance of Transparent Plas-E 11 Specification for Wire-Cloth Sieves for Testing Aggregates2 Insulating Materials for Testing3 tance of Transparent Plastics3 tics to Surface Abrasion3 Purposes4 3.Summary of Test Method 3.1 This te
7、st method consists of measuring and recording the haze and light transmission of a test specimen,mounting the specimen in the test fixture,and subjecting the specimen to a specific number of salt-blast cycles.After exposure to the abrasion,the haze and light transmission are remeasured to determine
8、any change in these values.3.2 The degree of abrasion is measured by the amount of change in haze and luminous transmission after exposure to the test.4.Significance and Use 4.1 Many types of plastics are used in the making of transparencies and enclosures or covers.It is the intent of this test met
9、hod to provide a means of determining the relative abrasion resistance of plastics or coatings,or both,to such operational uses as flying through frozen rain,snow,This test method is under the jurisdiction of ASTM Committee F-7 on Aerospace and AircraR and is the direct responsibility of Subcommitte
10、e F07.08 on Transparent Enclosures and Materials.Current edition approved April 19,1988.Published May 1988.Amiral Book o f ASTM Standards,Vol 04.03.Anniral Book of ASTM Standards,Vol 08.0 I.Annital Book o f ASTM Standards,Vol 14.02.and light hail.Impingement by dust,sand,and other small particles ca
11、n also cause abrasion damage.5.Apparatus 5.1 Abrader,as illustrated in Fig.1 consisting of a specimen holder,a nozzle,a salt supply,a dry-air supply,a mixing chamber,and a control panel.5.1.1 Specimen Holder,to support a test specimen in a horizontal position.A mask shall shield the specimen,on its
12、bottom side,such that a 25.4-mm(i-in.)diameter area centered 19 mm(0.75 in.)from the sides is exposed for testing.5.1.2 Nozzle,conforming to the requirements of Fig.i5 shall be positioned perpendicular to the test area with the tip of the nozzle located 127 mm(5.0 in.)from the test area.5.1.3 The sa
13、lt shall be dispensed into the airstream to serve as the abrading medium for the specimen.Salt shall be injected into the airstream at controlled intervals to provide cyclic abrasion pulses of 0 5 s salt blast followed by 2.0 s off,which can be counted to provide a prescribed number of abrasion cycl
14、es in a given time.Discard spent salt.5.1.4 Dry air or nitrogen,supplied at 25-i-0.5 psig setting at beginning of pulse,shall flow through the mixing chamber and nozzle to impinge on the test area of the specimen.5.1.5 Mixing Chamber,capable of drawing in and dis-persing a quantity of salt throughou
15、t the airstream in such a manner that it leaves the nozzle in high concentration and uniformly distributed within the pulse period.Determine the average quantity of salt dispensed in each pulse by measure-ment of the quantity of salt available before the series of cycles less the quantity remaining
16、after the series of cycles divided by the number of cycles.5.1.6 Control Panel,including the devices necessary for operation of the test equipment,It shall include a means of selecting the number of salt impingement cycles desired and a counter to record the number of cycles operated during the test.5.2 Integrating Sphere Photoelectric Photometer,as de-scribed in Method D 1003,to measure the light transmitted and scattered by the abraded surface.6.Reagents and Materials 6.1 Sodium Chloride Abrad
