1、 T 476 om-11 SUGGESTED METHOD 1946 TENTATIVE STANDARD 1949 PROVISIONAL METHOD 1976 OFFICIAL TEST METHOD 1984 REVISED 1991 REVISED 1997 REVISED 2001 REAFFIRMED 2006 REVISED 2011 2011 TAPPI The information and data contained in this document were prepared by a technical committee of the Association. T
2、he committee and the Association assume no liability or responsibility in connection with the use of such information or data, including but not limited to any liability under patent, copyright, or trade secret laws. The user is responsible for determining that this document is the most recent editi
3、on published. Approved by the Standard Specific Interest Group for this Test Method TAPPI CAUTION: This Test Method may include safety precautions which are believed to be appropriate at the time of publication of the method. The intent of these is to alert the user of the method to safety issues re
4、lated to such use. The user is responsible for determining that the safety precautions are complete and are appropriate to their use of the method, and for ensuring that suitable safety practices have not changed since publication of the method. This method may require the use, disposal, or both, of
5、 chemicals which may present serious health hazards to humans. Procedures for the handling of such substances are set forth on Material Safety Data Sheets which must be developed by all manufacturers and importers of potentially hazardous chemicals and maintained by all distributors of potentially h
6、azardous chemicals. Prior to the use of this method, the user must determine whether any of the chemicals to be used or disposed of are potentially hazardous and, if so, must follow strictly the procedures specified by both the manufacturer, as well as local, state, and federal authorities for safe
7、use and disposal of these chemicals. Abrasion loss of paper and paperboard (Taber-type method) 1. Scope1.1 This method determines the resistance of surfaces of paper and paperboard to the action of abrasion, either wet or dry, by measuring abrasion loss. This test is not applicable to the surfaces t
8、reated with wax or similar materials which would fill in the pores of the abrasive wheels. 2. Significance 2.1 Measurement of abrasion loss is quite complex and involves many factors including fiber type, material structure, and any additives or bonding agents used. Surface sizing may increase abras
9、ion resistance. 2.2 By combining abrasion test results with actual end use results, it is possible to predict usefulness and suitability of a product for a particular application, such as study or prediction of laser printer systems from feeder mechanism abrasion of paper or evaluation of the adhesi
10、on of fused toner. 3. Definitions 3.1 Abrasion: the wearing away of any part of a material by rubbing against another surface. 3.2 Resilient wheels: wheels that are rubber-based and distort to the contour of the surface of contact. 3.3 Non-resilient wheels: vitrified wheels that do not distort to th
11、e surface of contact. T 476 om-11 Abrasion loss of paper and paperboard / 2 (Taber-type method) 4. Apparatus 4.1 Abrading instruments1, consisting of a horizontal turntable with a center clamp, which revolves at 70 to 75 rpm, upon which the specimen is attached, and two weighted parallel arms, each
12、carrying a special abrasive-embedded rubber wheel, freely rotating on a ball-bearing horizontal spindle, and each resting on the specimen with a known dead-weight load and an adjustable vacuum system for debris removal (see Fig. 1). For the dry paperboard test, 1000 gf or 500 gf is used with non-res
13、ilient wheels. For the dry paper test, 500 gf or 250 gf is used with resilient wheels. For the wet test, 500 gf is used with the same wheels as used in the dry tests. In all cases, the type and grit of wheels shall be agreed upon by user and supplier. The surface of the table is covered with a disk
14、of soft rubberized material 0.762 mm (0.03 in.) thick. Each abrasive wheel is 44 to 51 mm (1 to 2 in.) in diameter and 12.7 mm (in.) thick and composed of a special finely screened and standardized abrasive. A revolution counter is attached to the table. The lines of contact of the wheels on the spe
15、cimen are at right angles to the parallel supporting arms and situated 26.2 mm (1.03 in.) from the center of the turntable towards the axis about which the supporting arms turn. The center of the line of contact of the wheel on the arm from which the turntable revolves is 31 mm (1 7/32in.) to the le
16、ft. In this manner, when in contact with the turning specimen, the two wheels revolve in opposite directions and exert a combined abrasive, compressive, and twisting action over a circular path approximately 3000 mm2(4.6 in.2) in area, twice during each revolution of the specimen. 4.1.1 For the wet
17、abrasion test, a rubber-covered turntable with an annular raised rim is used, to permit the surface of the specimen to be covered with water during the test. 4.2 Brush, soft brush about 12-13 mm (in.) wide with bristles about 25 mm (1 in.) long. 4.3 Filter paper, sintered-glass or Gooch crucible, fo
18、r wet abrasion residue. 4.4 Resurfacing turntable, a rubber-covered turntable on which an abrasive disc is mounted, for resurfacing the wheels. 4.5 Refacing disc, for resurfacing of resilient wheels. The refacing disc shall be 150 grit silicon carbide coated abrasive product, approximately 102 mm di
19、ameter with a 7-mm center hole. 4.6 Wheel refacer, with a diamond tool for resurfacing non-resilient wheels. 4.7 Analytical balance, to weigh to the nearest 0.001 mg. 4.8 Water, distilled or demineralized (for wet abrasion test). 4.9 Specimen mounting card, a cardboard piece with adhesive to attach
20、the sample. It is used to “stiffen” the test piece and make it easier to attach to the turntable (optional). Fig. 1. Abrading instrument (vacuum not shown) 1Names of suppliers of testing equipment and materials for this method may be found on the Test Equipment Suppliers list in the set of TAPPI Tes
21、t Methods, or may be available from the TAPPI Quality and Standards Department. 3 / Abrasion loss of paper and paperboard T 476 om-11 (Taber-type method) 5. Test specimen 5.1 If a lot of paper is being tested, select the test specimens in accordance with TAPPI T 400 “Sampling and Accepting a Single
22、Lot of Paper, Paperboard, Containerboard or Related Product.” 5.2 From each test unit, cut three or more square, octagonal, or circular specimen disks approximately 110 mm (4 in.) across, with a 6.35 mm (0.25 in.) center hole to permit clamping on the turntable. For paperboards more than about 3 mm
23、(0.118 in.) thick, especially for the wet test, it may be necessary to split or suitably reduce the thickness of the specimen, taking care not to affect the surface to be tested. For flexible materials, the specimen may be mounted on a rigid mounting card. The specimen and mounting card should then
24、be treated as the specimen (i.e., conditioned, weighed, mounted, and tested as a unit). NOTE 1: Unless it is specified which side of the specimen is to be tested, identify the sides in some appropriate manner, and report results for each side separately. 6. Conditioning For the dry abrasion test, co
25、ndition and test the specimens in an atmosphere in accordance with TAPPI T 402 “Standard Conditioning and Testing Atmospheres for Paper, Board, Pulp Handsheets and Related Products.” 7. Procedures 7.1 Dry abrasion test 7.1.1 Carefully brush the surface and edges of each test specimen. Weigh each spe
26、cimen to the nearest 0.001 g after punching the mounting hole. Clamp the specimen (and mounting card if being used) on the turntable. Reset the counter to zero. Mount the correct test wheels and weights as per section 4.1 and carefully lower them upon the specimen. Prepare the test wheels in accorda
27、nce with the manufacturers recommendations (see Appendix A). Allow the test to proceed until the endpoint is reached. Periodically remove accumulated debris with a brush, being careful to not disturb the underlying surface. Do not blow off debris. It has been found that a vacuum system for debris re
28、moval is essential to the precision of this method. When the test is complete, record the counter reading, remove the test specimen, and carefully brush off any loose fibers or particles. To avoid the effect of possible moisture loss of the sample, allow the sample to condition for at least 5 min an
29、d reweigh. Record the weight loss in milligrams (L). The endpoint for uncoated specimens is the point at which fiber disruption occurs. The endpoint for coated specimens is either when the surface coating is removed and the underlying layer is exposed (multilayer coating) or when the fibers of the u
30、nderlying substrate are disturbed (single layer coating). 7.2 Wet abrasion test 7.2.1 Thoroughly clean the rimmed turntable and mount the specimen to be tested. Mount correct test wheels (see section 4.1) and 500 gf load on each arm and lower them upon the specimen. Reset the counter to zero. Add su
31、fficient distilled or demineralized water, at 23 2C, to flood the upper surface of the specimen and immediately begin test. Do not use the vacuum during the wet abrasion test. Allow the test to proceed for a sufficient length of time so that the surface of the test specimen is just completely remove
32、d. During the test, do not use the brush nor disturb the action of the wheels. Record the counter reading. 7.2.2 To prevent spillage, use a syringe to transfer some of the liquid from the rimmed table. Remove the rimmed table, and pour off the remaining liquid into a clean beaker or glass dish. Remo
33、ve the specimen and with a washbottle or gentle jet of distilled or demineralized water, wash all the loose material from the surface of the specimen and from the inside of the turntable into the dish. Using a brush, remove any fibrous particles adhering to the wheels into the dish. 7.2.3 Filter the
34、 liquid and washings on a dried, tared filter paper, or sintered-glass or Gooch crucible. Dry at 105 3C to constant weight. Calculate the milligrams of airdry material removed, using the products known equilibrium moisture content at the time of original weighing. NOTE 2: If the actual equilibrium m
35、oisture content is not known, then use an assumed value based on past history (7% is typical) and state this in the report. NOTE 3: Whenever possible, a prescribed number of revolutions to determine the end of the test should be used. This becomes a constant and makes sample comparison simpler. Abra
36、sion loss becomes actual rather than calculated and removes the subjective determination of surface disruption. T 476 om-11 Abrasion loss of paper and paperboard / 4 (Taber-type method) 8. Calculation Calculate the abrasion loss, per 1000 revolutions of the turntable, as follows: Abrasion loss = 100
37、0 L/R where L = air dry material removed, mg R = counter reading 9. Report Report abrasion loss in milligrams/1000 revolutions as the average result from a specified side of at least three specimens to the nearest two significant figures and the number of revolutions to the endpoint. Specify type of
38、 wheel used, test load and whether test was done wet or dry. When doing wet abrasion, state original average air dry moisture content used in calculation or what the assumed moisture content was. Also report the number of revolutions and the actual weight loss to the nearest 0.001 mg. 10. Precision
39、10.1 Repeatability, (as defined by TAPPI T 1200 “Interlaboratory Evaluation of Test Methods to Determine TAPPI Repeatability and Reproducibility”). 10.1.1 Dry abrasion test: Coated side = 84.3% based on 9 labs and 10 replicate samples Uncoated side = 35.7% based on 7 labs and 10 replicate samples 10
40、.1.2 Wet abrasion test: Coated side = 88.5% based on 4 labs and 10 replicate samples 10.2 Reproducibility, (as defined by TAPPI T 1200). 10.2.1 Dry abrasion test: Coated side = 144.6% based on 9 labs and 10 replicate samples Uncoated side = 136.6% based on 7 labs and 10 replicate samples 10.2.2 Wet
41、abrasion test: Coated side = 163.4% based on 4 labs and 10 replicate samples 10.3 The round robin test conducted by an independent laboratory with ten different laboratories showed wide variation in reproducibility. The reason for this wide variation was believed to be due to difference in endpoint
42、consideration by each participating lab. Each lab defined the endpoint differently as per their needs. Each lab, however, considered the test valid and very useful. The condition of the instrument and the wheels (new vs. old) may also be a factor affecting variability. Individuals should determine i
43、f the repeatabilites and reproducibilities are satisfactory for their specific purpose. 11. Keywords Abrasion, Abrasion resistance, Bonding strength, Surface strength, Coatings. 12. Additional information 12.1 Effective date of issue: September 27, 2011. 5 / Abrasion loss of paper and paperboard T 4
44、76 om-11 (Taber-type method) 12.2 The principal changes made in the 2011 revision are the addition of a figure, correction of the distance of the wheels from the center of the turntable, addition of wheel resurfacing equipment, addition of the inner diameter of the disc center hole, addition of a no
45、te in the Appendix, and some editorial changes. 12.3 The quantity of material removed as a result of wheel wear in the wet abrasion test increases the abrasion loss slightly, but in general, this increase will be insignificant. It may be corrected approximately by determining the ash of the filtered
46、 material and the ash of the original paper or paperboard in accordance with TAPPI T 413 “Ash in Paper and Paperboard” and making the proper adjustment. Appendix A: Calibration and maintenance A.1 Prior to testing, ensure that wheels have been resurfaced according to the manufacturers recommendation
47、. Resurface the wheels as follows: NOTE 4: Due to clogging of the surface crevices with abraded debris, the abrading wheels should be resurfaced after testing a fiber surface containing fillers or coatings. To ensure that the abrading function of the wheels is maintained at a constant level during h
48、igher cycles tests, wheels should be resurfaced after each 1000 revolutions. A.1.1 When refacing resilient wheels attach a 150 grit abrasive disk to the specimen holder. Lower the resilient wheels on the surface with the 500 gf test load attached. Cycle until the wheels contact area returns to origi
49、nal color. During the resurfacing operation, continually remove abraded particles from the wheels and disk by vacuuming or with the brush. Renewal of the wheel faces is indicated by the clearing up of the initial colored track on the abrasive disk. A.1.2 When refacing nonresilient wheels set up a diamond wheel refacer. Mount both wheels on the arbor and tighten the nut. Lower the refacer wheel guard and turn the refacer on. Screw in the diamond tool until the diamond can be heard to just touch the wheel. Then move the diamond out of the wheel
