ASTM D – Designation: D – 08 Standard Test Methods for Measuring Adhesion by Tape Test. Buy ASTM D TEST METHODS FOR MEASURING ADHESION BY TAPE TEST from SAI Global. ASTM D Historical Standard: ASTM D Standard Test Methods for Measuring Adhesion by Tape Test. SUPERSEDED (see Active link, below).
|Published (Last):||27 September 2007|
|PDF File Size:||18.55 Mb|
|ePub File Size:||1.83 Mb|
|Price:||Free* [*Free Regsitration Required]|
ASTM D cross h D — 08 Standard Test Methods for Measuring Adhesion by Tape Test1 This standard is issued under the xed designation D ; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of 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. This standard has been approved for use by agencies of the Department of Defense. NOTE 1—This test method has been reported being used to measure adhesion of organic coatings on soft substrates asgm example, wood and plastic. Issues with plastic substrates are noted in Appendix X1.
ASTM D3359 Measuring Adhesion by Tape Test
A similar test method, ISOpermits tests on soft substrates for example, d3359-008 and plaster. Precision and bias data on the later is lacking. Test Methods D was developed with metal as the substrate and, in the absense of supporting precision and bias data, is so limited. Summary of Test Methods 3. Also, Test Method B is not considered suitable for lms thicker than 5 mils m.
NOTE 2—Subject to agreement between the purchaser and the seller, Test Method B can be used for thicker lms if wider spaced cuts are employed. They do not distinguish between higher levels of adhesion for which more sophisticated methods of measurement are required.
NOTE 3—It should be recognized that differences in adherability of the coating surface can affect the results obtained with coatings having the same inherent adhesion.
The values given in parentheses are for information only. Current edition approved Feb. Originally approved in Last previous edition approved in as D — Signicance and Use 4. Because the substrate and its surface preparation or lack of it have a drastic asgm on the adhesion of coatings, a method to evaluate adhesion of a coating to different substrates or surface treatments, or of different coatings to the same substrate and treatment, is of considerable usefulness in the industry.
The intra- and inter-laboratory precision of this test method is similar to other widely-accepted tests for coated substrates for example, Test Method D and Test Method Dbut this is partly the result of it being insensitive to all but large differences in adhesion.
The limited scale of 0 to 5 was selected deliberately to avoid a false impression of being sensitive. Apparatus and Materials 5. It is of particular importance that the cutting edges be in good condition.
Because of the variability in adhesion strength from batch-to-batch and with time, it is essential that tape from the same batch be used when tests are to be run in different d335908. If this is not possible the test method should be used only for ranking a series of test coatings.
NOTE 5—Coatings should be applied in accordance e3359-08 Practice Dor as agreed upon between the purchaser and the seller. NOTE 6—If desired d339-08 specied, the coated test panels may be subjected to a preliminary exposure such as water immersion, salt spray, or high humidity before conducting the tape test. The conditions and time of exposure will be governed by ultimate coating use or shall be agreed upon between the purchaser and seller. For tests in the eld, ensure that the surface is clean and d359-08.
Extremes in temperature or relative humidity may affect the adhesion of the tape or the coating. After immersion, clean and wipe the surface with an appropriate solvent which will not harm the integrity of the coating. Then dry or prepare the surface, or both, as agreed upon between the purchaser and the seller.
When making the incisions, use the v3359-08 and cut through the coating to the substrate in one steady motion. If the c3359-08 has d3359-088 been reached make another X in a different location.
Do not attempt to deepen a previous cut as this may affect adhesion along astj incision. Remove aastm additional length at a steady that is, not jerked rate and cut a piece about 75 mm 3 in. Smooth the tape into place by nger in the area of the incisions and then rub rmly with the eraser on the end of a pencil.
The color under the transparent tape is a useful indication of when good contact has been made. The manufacturer of this tape and the manufacturer of the tape used in the interlaboratory study see RR: Dhave advised this subcommittee that the properties of these tapes were changed. Users of it should, therefore, check whether current material gives comparable results to previous asttm material. For large structures make sufficient tests to ensure that the adhesion evaluation is representative of the whole surface.
Discard cutting tools that develop nicks or other defects that tear the lm. If the adhesion strength of the awtm has not been determined, report the specic tape used and its manufacturer. Precision and Bias 6 9. Apparatus and Materials It is of particular importance that the cutting edge or edges be in good condition.
It should be noted, however, that multitip cutters8 provide good results only on test areas sufficiently plane that all astk edges contact the substrate to the same degree.
Check for atness with a straight edge such as that of the tempered d3359-8 rule After drying or testing the coating, conduct the tape test at room temperature as dened in Specication Dunless D standard temperature is required or agreed.
For lms thicker than 5 mils muse Test Method A. Cut through the lm to the substrate in one steady motion using just sufficient pressure on the cutting tool to have the cutting edge reach the substrate. When making successive single cuts with the aid of a guide, place the guide on the uncut area. If the metal has not been reached make another grid in a different location. Your comments will receive careful consideration at a meeting of the responsible technical committee,1 which you may attend.
However, the precision values given in To ensure good contact with the lm rub the tape rmly astn the eraser on the end of a pencil.
The color under the tape is a useful indication of when good contact has been made.
ASTM D – 08 Standard Test Methods for Measuring Adhesion by Tape Test
Rate the adhesion in accordance e3359-08 the following scale illustrated in Fig. Small akes of the coating are detached along edges and at intersections of cuts. The coating has aked along the edges and on parts of the squares.
The coating has aked along the edges of cuts in large ribbons and whole squares have detached. Flaking and detachment worse than Grade 1. Precision and Bias 6 As Mittal 1 10 has pointed out, the answer is both yes and no. It is c3359-08 to state that at the present time no test exists that can precisely assess the actual physical strength of an adhesive bond.
But it can also be said that it is possible to obtain an indication of relative adhesion performance. Criticism of these tests arises when they are used to quantify the strength of adhesive bonding. But this, in fact, is not their purpose. Direct tests include the Hesiometer and the Adherometer 2. Common methods which approach the direct tests are peel, lapshear, and tensile tests. Criteria deemed essential for a test to warrant large-scale acceptance are: There generally is difficulty, however, in relating these tests to basic adhesion phenomena.
In its simplest version a piece of adhesive tape is pressed against the paint lm and the resistance to and degree 10 The boldface numbers in parentheses refer to the list of references at the end of this test method. Since an intact lm with appreciable adhesion is frequently not removed at all, the severity of the test is usually enhanced by cutting into the lm a gure X or a cross hatched pattern, before applying and removing the tape.
Adhesion is then rated by comparing lm removed against an established rating scale. If an intact lm is peeled cleanly by the tape, or if it debonds just by cutting into it without applying tape, then the adhesion is rated simply as poor or very poor, a more precise evaluation of such lms not being within the capability of this test. Both test methods are used to establish whether the adhesion of a coating to a substrate is at an adequate level; however they do not distinguish between higher levels of adhesion for which more sophisticated methods of measurement are required.
Major limitations of the tape test are its low sensitivity, applicability only to coatings of relatively low bond strengths, and non-determination of adhesion to the substrate where failure occurs within a single coat, as when testing primers alone, or within or between coats in multicoat systems. For multicoat systems where adhesion failure may occur between or within coats, the adhesion of the coating system to the substrate is not determined.
Applied to metals, it is economical to perform, lends itself to job site application, and most importantly, after decades of use, people feel comfortable with it.
It is assumed that coating removal occurs when the tensile force generated along the latter interface, which is a function of the rheological properties of the backing and adhesive layer materials, is greater than the bond strength at the coating-substrate interface or cohesive strength of the coating.
In actuality, however, this force is distributed over a discrete distance O-A in Fig. A signicant compressive force arises from the response of the tape backing material to being stretched. Thus both tensile and compressive forces are involved in adhesion tape testing. Several factors that contribute to these differences include coating composition and topology: Further, the tape test does not give an absolute value for the force required for bond rupture, but serves only as an indicator that some minimum value for bond strength was met or exceeded 7, e3359-08.
By design it was made as simple as possible to perform, and requires a minimum of specialized equipment d33599-08 materials that must meet certain specications. Key steps that directly reect the importance of operator skill include the angle and rate of tape removal and the visual assessment of the tested sample.
It is asm unexpected that different operators might obtain different results 7, 8. If the peel angle and rate vary, the force required to remove the tape can change dramatically. These effects are related as they reect certain rheological properties of the backing and adhesive that are molecular in origin. Variation in pull rate and peel angle can effect large differences in test values and must be minimized to assure reproducibility 9.
The nal step in the test is visual assessment of the coating removed from the specimen, which is subjective in nature, so that the coatings can vary among individuals evaluating the same specimen 9. Justication for the cutting step is reasonable as cutting provides a free edge from which peeling can begin without having to overcome the cohesive strength of the coating layer.
For coatings on soft substrates, issues include how deep should this cut penetrate, asym is it possible to cut only to the interface?
The central issues are that the test on plastics lacks reproducibility and does not relate to the intended application.