Comparison of test principles
Although both peel and tear tests are used to evaluate the resistance of materials to failure, there are significant differences in their mechanical nature and stress form. Peel testing mainly occurs at the adhesive interface or laminated structure, and the loading direction is usually at an angle to the material plane, recording the peel force per unit width. The tear test pays more attention to the force value required for the expansion of the existing incision or defect inside the material, and the loading direction is generally perpendicular to the incision direction to record the tear force. These two types of tests correspond to different standards: peel tests often refer to ASTM D903 and GB/T 2792, and tear tests are mostly based on ASTM D1004, ISO 34-1, etc. Understanding the differences in principle is the first step in the selection of a single column testing machine.
The force value range is critical
Peel tests typically require lower force values, such as tapes, labels, or flexible packaging materials with peel forces between 0.5 N and 50 N. Tear testing has a wider range of force values, with tear forces of only a few Newtons on tissue paper or film and hundreds of Newtons on thicker leather and textiles. When selecting, it is necessary to ensure that the testing machine covers the expected maximum value and works in the range of 10% to 80% of the range to ensure accuracy. Single-column racks can be configured with different capacitance sensors (e.g., 50 N, 200 N, 1 kN) to flexibly adapt to both types of testing. The force value accuracy should be at least better than the indicated value level 1 (i.e., ±1%), and it is recommended to give priority to 0.5 level sensors.
| Test type | Typical force value range |
| Peel test (adhesive tape) | 1 N～30 N |
| Peel Test (Laminated Film) | 5 N～50 N |
| Tear Test (Paper) | 2 N～20 N |
| Tear Test (Textiles) | 20 N～200 N |
| Tear test (leather) | 50 N～500 N |
Speed control differences
Peel testing requires strict displacement rate control, often stipulating a constant rate of 300 mm/min or higher, and requiring a stable speed throughout the loading process. The single-column testing machine should have a wide range of servo speed regulation capabilities, with a typical range of 0.01 mm/min to 500 mm/min, and be able to maintain closed-loop control at high speeds. Tear testing is relatively less sensitive to speed, but some standards, such as Elmendorf tearing, require impact loading, and single-column machines require special tear grippers and cushioning devices. In addition, in order to avoid interface fluctuations during the peel test, it is recommended that the testing machine has a low-inertia transmission mechanism, such as a ball screw with a servo motor.
Fixtures and accessories are adapted
Peel testing requires special fixtures, such as T-shaped peel fixtures, 90° peel fixtures, or 180° peel fixtures, which should be able to hold thin soft specimens stably without slippage or stress concentration. Tear testing is commonly used with pant-shaped, trouser-shaped, or pants-shaped cut-out fixtures, as well as trapezoidal or right-angled tear fixtures. The rack space of the single-column testing machine is limited, the fixture installation interface needs to be standardized (such as M6 or 1/2 inch threaded interface), and the weight of the fixture should not exceed 10% of the sensor range. For large-stroke tearing, the fixture should also consider the space margin when the specimen is stretched to avoid the clamp collision limit. When selecting, it is advisable to confirm that the supplier can provide a complete set of fixture kits.
Rack travel and space
Single-column testing machines typically offer an effective tensile stroke of 300 mm to 600 mm. In peel tests, especially when the specimen is long or needs to be peeled continuously for a long distance (such as the peel length is more than 200 mm), sufficient travel is required to avoid reloading in the middle. The amount of fracture deformation in the tear test is usually small, but the tear elongation of some ductile materials such as elastomers can reach 200%, so the stroke needs to meet the full length of the specimen plus the deformation allowance. The rack width determines the lateral holding space of the fixture, and for larger width laminates or textile tears, a model with a wider desktop width should be chosen. In addition, some single-column machines can be equipped with an optional raised column to extend the stroke range.
| Test type | Minimum itinerary recommended |
| Peel Test (General) | 300 mm |
| Peel test (long specimen) | 500 mm |
| Tear Test (Film) | 250 mm |
| Tear test (elastomer) | 400 mm |
Data acquisition frequency
The force curve for peel testing is usually gentle, but to capture microscopic adhesion fluctuations, it is recommended to acquire data at least 100 Hz. In tear testing, crack propagation is often instantaneous, and force values can plummet within milliseconds, so data acquisition on a single-column testing machine should be 1 kHz or more to accurately record peak forces and fracture behavior. Some high-performance single-column machines support adjustable sampling rates, which should be prioritized when selecting. At the same time, the data processing software needs to be able to automatically identify the average force or the maximum tearing force during the peeling platform, and output the charts and statistical parameters required by the standard.
Reference source
ASTM D903-98(2017) Standard Test Method for Peel or Stripping Strength of Adhesive Bonds
ISO 34-1:2015 Rubber, vulcanized or thermoplastic — Determination of tear strength — Part 1: Trouser, angle and crescent test pieces
GB/T 2792-2014 Test method for peel strength of adhesive tape
ASTM D1004-21 Standard Test Method for Tear Resistance (Graves Tear) of Plastic Film and Sheeting