1、Designation: C 648 04Standard Test Method forBreaking Strength of Ceramic Tile1This standard is issued under the fixed designation C 648; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parent
2、heses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of the break-ing strength of glazed ceramic wall tile, ceramic mosaic tile,quarry tile, and paver tile, havi
3、ng a facial area of at least 1 in.2(6.4 cm2).1.2 The values stated in inch-pound units are to be regardedas the standard. The metric equivalents of inch-pound unitsmay be approximate.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is there
4、sponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C 242 Terminology of Ceramic Whitewares and RelatedProductsE 178 Practice for Dealing wit
5、h Outlying Observations3. Terminology3.1 Definitions:3.1.1 For definitions of the types of tile listed in Section 1,refer to Terminology C 242.4. Summary of Test Method4.1 The test method consists of supporting the tile on theends of three cylindrical rods, or on three ball bearings for tileshaving
6、an actual facial area of 9 in.2(58 cm2) (or less),arranged in an equilateral triangle, and applying force at adefinite rate to the center of the tile, which coincides with thecenter of the triangular support, until the specimen breaks.NOTE 1The size (facial dimensions) of otherwise equal tile affect
7、s thevalue of breaking strength obtained by this test method. For instance, a 6by 6-in. (152 by 152-mm) tile equal in mature body properties andthickness to a 414 by 414-in. (108 by 108-mm) tile will have a breakingstrength higher than the 414 by 414-in. tile.5. Significance and Use5.1 The test meth
8、od provides means for establishingwhether or not a lot of ceramic tile meets the strengthrequirements which may appear in tile specifications. Tilestrength is the force in pounds-force (or newtons), as read fromthe pressure gage, necessary to cause the tile to break.6. Apparatus6.1 Specimen-Support,
9、 consisting of a 512 by 512 by 1-in.(139.7 by 139.7 by 25.4-mm) steel block. Three14-in. (6.4-mm) diameter and38-in. (9.5-mm) deep tapped holes arearranged in an equilateral triangle having 3-in. (76.2-mm) sidesand whose circumscribed circle has a radius of 1.732 in. (44.0mm). The equilateral triang
10、le is located on the steel block sothat its center coincides with that of the steel block and one sideof the triangle runs parallel to one side of the steel block. Three38-in. diameter steel rods, 138 in. with (34.9 mm) long, one endthreaded for a distance of38 in. with the same14-in. thread asthe t
11、apped holes, and the other end ground flat, fit into the threeholes. In a similar manner, a second set of three38-in. diametersteel rods, but34 in. (19.0 mm) long only, are threaded on oneend for a distance of38-in., are ground flat on the other end andfit three other14-in. tapped holes. The three14
12、-in. holes, tappedfor a distance of38 in. to receive this second set of steel rodsare located at the apexes of an equilateral triangle having112-in. (38.1-mm) long sides and whose circumscribed circlehas a radius of 0.866 in. (22.0 mm). This second equilateraltriangle is located within the first one
13、 in such a manner that itscircumscribed circle is identical with the inscribed circle of thefirst triangle, and its sides are parallel to those of the largertriangle. The ball bearing support consists of three18-in.(3.2-mm) ball bearings arranged in an equilateral triangle, withsides of 14 mm concen
14、tric and parallel with the other triangles.The bearings are embedded in the block to the extent of halftheir volume. The steel block has four more14-in. tapped holesto receive socket head cap screws for holding four registrystops. One of these holes is located in the center of one side,14in. in from
15、 the edge. Another of these is located in the centerof an adjacent side14 in. from the edge. The other two arelocated on an adjacent side,14 in. in from the edge, spaced 2in. (50.8 mm) apart, with one located 134 in. (44.4 mm) from1This test method is under the jurisdiction of ASTM Committee C21 on
16、CeramicWhitewares and Related Products and is the direct responsibility of SubcommitteeC21.06 on Ceramic Tile.Current edition approved April 1, 2004. Published May 2004. Originallyapproved in 1970. Last previous edition approved in 1998 as C 648 98.2For referenced ASTM standards, visit the ASTM webs
17、ite, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United Stat
18、es.one of the corners of the first side. The two single hole registrystops are used with the ball bearing support. The double holeregistry stop and the adjacent edge single stop are to be usedwith the sets of rod supports. Three of the registry stopsdesigned for use with the cylindrical rod supports
19、 consist of18-in. (3.2-mm) thick steel strips,34 in. wide, 2 in. long, witha14-in. wide slot extending for the full 2-in. length of the strip.The slot is open on one end and the other end of each steel striphas a34 in. wide and 112 in. high projection,18 in. thick,which will contact the edges of the
20、 tile when in proper positionfor use. The other two registry stops, designed for use with theball bearing support, have exactly the same dimensions exceptfor their projection height which is58 in. The projection isobtained by making the steel strips actually 312 in. (88.9 mm)long and bending them at
21、 right angles to obtain the 112-in. or58-in. (38.1-mm or 15.9-mm) high projection. Each of the threeregistry stops can be fastened with washer and socket head capscrew through its slot in any one of numerous positions. Beingadjustable, they serve as registry stops for the different sizes oftile whic
22、h may be broken over these supports. For tile ofdimensions 414 in. (107.9 mm) or smaller, the projections willbe located on that end of the strip nearest to the support block;for tile having dimensions larger than 414 in., the strips arereversed so that the projections are located on the end of thes
23、teel strips away from the support block (see Fig. 1). Forcertain mosaic tiles with dimensions of less than 1 in. (25.4mm) length, it is necessary to reverse the position of theregistry stops so that the tile is supported with the slot ends inorder to avoid interference with the force applicator.6.2
24、Force Applicator Force is applied in the exact centerof the triangular support by means of a12-in. (12.7-mm)diameter stainless steel ball bearing, countersunk to a depth of1764 in. (6.7 mm) into one end of a 1-in. (25.4-mm) diameterand 2-in. long steel rod. A332-in. (2.4-mm) thick retainingcollar pr
25、events the ball from falling out of its recess and isfastened to the steel rod by four332-in. 3-48 NC screws,38 in.FIG. 1 Support Block Assembly (See Table 1)C648042(9.5 mm) long, with countersunk heads. The opposite end ofthe steel rod is reduced in diameter for the proper distance andthreaded to f
26、it its female counterpart of the testing machine (seeFig. 2).6.3 Testing Machine Any apparatus, preferably motordriven, capable of maintaining a uniform load application rateof 800 to 1100 lbf (3600 to 4900 N)/min and large enough toaccommodate the steel support block, shall be consideredsuitable te
27、sting equipment. The machine must be equippedwith an interchangeable gage, which has a special peakloadindicator that will remain at the highest reading reached duringthe test, until reset by hand to the zero point. The scale of thegage used shall have such a range that the breaking load of thetest
28、specimens falls between 10 and 90 % of the scale capacity.The scale shall be graduated into 100 or more equal incre-ments.7. Test Specimen7.1 Size of Sample Select tile specimens at random fromthe lot to be tested and in the quantities designated in thespecification. However, the number of tile per
29、sample shallnever be less than 10.7.2 Cutting of SpecimensIt may be necessary to cut tilesamples down to a size that will fit the testing apparatus. A wetsaw should be used for this. An equal amount may be trimmedfrom each edge such that the sample is the largest possible sizethat can be accommodate
30、d by the testing apparatus.7.3 Preparation of SpecimensRemove any loosely adher-ing clay particles from the back of each tile with a stiff brush.8. Procedure8.1 Place the steel support block into the testing machine sothat the load applicator is directly above the center of the steelblock. For tile
31、having actual facial area greater than or equal to62 in.2(400 cm2), use the support and rods represented by thelarger triangle. For tile with actual facial areas greater than to9 in.2and less than 62 in.2(58 cm2and 400 cm2) use thesmaller triangle and rod supports. For actual facial area greaterthan
32、 1 in.2and less than or equal to 9 in.2(6.4 cm2and 58 cm2)use the ball bearing support.8.2 Find the exact center of one tile of the sample bydrawing lines across the face of the tile, connecting diagonallyopposite corners, and place this tile on the proper three-pointsupport. The face of any tile to
33、 be broken must always be in anupward position. In the case of reversible tile, such as unglazedceramic mosaic tile, it is immaterial which side of the tile is up.Tile with directional back designs must be placed on thetriangular support so that any ribs or grooves run parallel tothose support rods
34、which are arranged parallel to one side ofthe steel block.8.3 Lower the load applicator and move the tile with thediagonal lines so that its center is directly below the center ofthe load applicator ball. With the tile in this position, move thethree adjustable registry stops so that their vertical
35、projectionsare in contact with two adjacent sides of the tile and fastenthem in that position. It may be necessary to remove one of thesupport rods, by unscrewing it from the 512-in. (140-mm)square steel block, in order to position all the registry stopswithout interference. If the tile is a size su
36、ch that the verticalprojections on the registry stops will interfere with the forceapplication, use the slot ends of the registry stops to fix theposition of the tile. Except for minor size variations, theregistry stops will now locate every tile of the sample in therelatively same spot on the suppo
37、rt, so that force is applied inthe approximate center of each tile.8.4 Position a safety shield around the apparatus so that noperson or property will be injured from possible contact withbroken tile. The use of a safety shield is mandatory in testingthe breaking strength of ceramic mosaic tile, whi
38、ch can breakinto shrapnel-like fragments.8.5 Whenever the approximate force required to break theparticular type of tile is not known, it is necessary to breakseveral tile prior to starting the test in order to establish therange of the gage to be used. Install the proper gage and set thepeak-load i
39、ndicator to zero.TABLE 1 Conversion of Dimensions Appearing in Figs. 1 and 2in. mm in. mm18 3.2 138 34.914 6.4 112 38.11764 6.7 14764 44.138 9.5 134 44.412 12.7 2 50.80.645 16.4 212 63.534 19.0 234 69.82532 19.8 31532 88.10.866 22.0 512 139.71 25.4FIG. 2 Force Applicator Details (See Table 1)C648043
40、8.6 Apply force at the rate of 800 to 1100 lbf (3600 to 4900N)/min until the tile actually breaks into two or more pieces.Read the force on the gage by interpolation to the nearest 1 lbf(4 N). Record this pressure and reset the gage to zero.8.7 Remove any debris from the surface of the steel blockwi
41、th a brush. Place the next tile on the triangular support withtwo adjacent sides in contact with the registry stops and repeatthe operation until all of the tile in the sample have beenbroken.9. Calculation9.1 Average the breaking forces for all of the tile in thesample.9.2 If any one individual bre
42、aking force appears to deviatemarkedly from the others of the sample, it may be eliminatedbefore the average is calculated only after the criteria inPractice E 178 have been applied and justify elimination.9.3 Should it become necessary to eliminate more than20 % of the individual values in a sample
43、 in accordance with9.2, repeat the test on sample containing twice the number ofspecimens in the original one. In that case, only breaking forcesfrom the repeat test shall be used to arrive at the averagestrength of the sample.10. Report10.1 Report the following information:10.1.1 Name and model num
44、ber of the testing machine,10.1.2 Range of the gage used,10.1.3 Identification of the triangular support used in test-ing, by stating the length of its sides,10.1.4 Type of tile tested, whether glazed or unglazed.10.1.5 Number of specimens in the sample; also statewhether it is a repeat test, and10.
45、1.6 Average strength in pounds-force (or newtons) of thesample.11. Precision and Bias11.1 The maximum difference between breaking strengthsdetermined by laboratories testing tile from the same lots was20 % of the lower value, and the difference was less than 5 %for 50 % of the lots tested. An overal
46、l difference of 712 %existed between laboratories in a test series of 19 lots of walltile.12. Keywords12.1 breaking strength; ceramic tileASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this st
47、andard 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 time by the responsible technical committee and must be reviewed every five years a
48、ndif 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 receive careful consideration at a meeting of theresponsible technical committee,
49、 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 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 throug
