Roller peel test

While detail may be found in the ASTM D-3330 or PSTC-1 and PSTC-2 standards, the peel test is typically carried out as follows The tape is conditioned at 23°C and 50% relative humidity for 1 day. Next, the tape is rolled down with a weighted standard roller onto a clean test substrate (usually polished 302 stainless steel), allowed to dwell for a specified time (usually 1 min), and then clamped with the testing fixture in the test machine and peeled at a specified rate. 

The floating roller peel test is used when one adherend is flexible and the other is rigid. The flexible member is peeled through a spool arrangement to maintain a constant angle... 

Peel Test (PSTC-1) - Cold rolled steel "Q-Panels" (Q-PanelCo.) were used. A one-inch wide strip of coated Mylar is bonded to the panel under pressure of a 4 1/2-lb. roller. 

A T-peel test is shown in Fig. 27.2. The specimen is usually 1 in. (2.54 cm) wide and is described in Standard Test Method ASTM D1876 [6]. This specimen is symmetrical (both adherends are the same thickness). Other peel test specimens are not symmetrical, such as the floating roller peel test [7] or the climbing drum peel test [8]. The test measures the fracture resistance of an adhesive under conditions in which the adherends may plastically deform. In the tables presented later, the peel strength is given in Newtons per centimeter of width (N/cm) and in tmits of pounds per inch width (piw). The latter is shown in parenthesis. In some cases, the peel strength is derived from climbing drum peel measurements in which the results are presented in torque, in. Ib/in. For pressure sensitive adhe-... 

An alternative to the climbing drum peel test is the floating roller peel test, described in ASTM D3167-76. Direct comparisons cannot be made between the two tests because the floating roller test induces a more severe peel angle than the climbing drum. 

Samples for the floating roller peel test can be a bonded honeycomb type or any adhesive assembly consisting of a rigid adherend and a relatively flexible adherend. Test specimens are typically aluminum with the flexible adherend being 0.025 inch thick and the rigid adherend at 0.064 inch thickness (see Figure 16). Samples are tested in a tensile machine at a crosshead speed of 6 inches/min for three inches of peel distance. Peel strengths are reported in pounds per inch of peel width. 

Another commonly performed peel test, the roller peel test, is described in... 

Fig, 14. Roller peel test conliguration (ASTM D3167). 

For any values of P and D there will be an angle, 6r, at the debond point as shown in Fig. 10. For an applied force P only a fraction, i.e. (1 — fx)P, is applied at the peeling front since friction arises in the roller, where fx is the coefficient of friction. The energy release rate, G, for this roller-assisted peel test is given by ... 

Fig. 11. The determination of the adhesive fracture energy, Gc, using a roller-assisted 90° peel test, and a calibration curve.

Fig. 12. Roller-assisted 90° peel test results for nickel foils bonded to aluminium alloy using an epoxy adhesive, after roughening of the foils with 150 mesh SiC grains (coarse sanding) or 400 mesh SiC grains (fine sanding) [60].

Peel ( ) Peel strength for stated test sample configuration, e.g. T peel, floating roller, bell, sandwich, etc. Units vary for different test pieces. 

Other repair adhesive with similar uses FM235-M (0.4kg/m ). X (wet) 7 days. 70°C 8%RH,RT test. Peel - Floating Roller. ... 

DIN 53289 Testing of adhesives for metals and adhesively bonded metal joints floating roller peel test. 

ISO 14676 1997 Adhesives - Evaluation of the effectiveness of surface treatment techniques for aluminium - Wet-peel test by floating-roller method... 

Fig. 15. Floating roller peel test head and specimen (D-3167).

Figure 34 90° peel test also called floating roller peel (a) panel prior to bonding (cut into 25 mm strips after bonding) (b) peel test apparatus (all dimensions in mm). 

Floating Roller and BS 5577 Peel Fig. 49 shows a typical peeling rig for the floating roller peel test. The differences between this test and the BS 5577 specification are the peeling angle, which is about 70° for the floating roller or Bell peel test and 90° for the BS 5577 test, and the aluminium alloy used BS 5577 uses a much softer alloy. 

Figure 49 Schematic of the floating roller peel test.

Fig. 86. Various forms of the peel test (a) 180° T-peel test for flexible-to-flexible assembly (b) 180° peel test for flexible-to-rigid assembly (c) climbing drum test (d) floating roller test (dimensions in mm).

For sandwich structures, the climbing drum method is clearly to be preferred the simplest standard peel test is the T-peel method, while the floating roller technique gives more repeatable results. The 180° test has little to recommend it beyond simplicity. 

Clearly, while comparative measurements can be made using the above types of peel test, the results obtained will depend upon such factors as the mechanical properties of the peel arms, their thickness, and also upon such factors as the applied peel angle, and the effective local peel angle at the peel front. Also, in a study to evaluate these different types of peel test, Kawashita and coworkers (2005) demonstrated that in tests such as the floating roller peel test, frequently the peel arm does not conform to the roller geometry. This was identified using a modified and partially cutaway apparatus, which allowed the conformation to be evaluated. 

Manual testing machine consisting of a peel roller and a handle lever for peel tests of specimens... 

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