Information on the most widely used ASTM standards within the materials testing industry
ASTM D5041: Standard Test Method for Fracture Strength in Cleavage of Adhesives in Bonded Joints
ASTM D5041 test method covers the determination of fracture strength in cleavage of adhesive bonds when tested on standard reinforced plastic specimens and under specified conditions of preparation and testing.
It describes the fracture strength testing of flat adhesively bonded reinforced plastic specimens. It involves imposing controlled cleavage stresses to split apart the specimen using a movable wedge.
The ASTM D5041 adhesive shear strength is expressed in Mpa or Gpa.
Apparatus used in ASTM D5041:
Drive Mechanism: Ensures uniform, controlled crosshead velocity relative to the fixed member.
Load Indicator: Measures the total compressive load on the specimen with accuracy within ±1% of the maximum load.
Wedge: A 45° angle wedge (aluminum or steel) with smooth sides and a radius of 0.02 mm is recommended. Stainless steel is recommended for durability.
Removable Tip (Optional): feature to prevent test data distortion if the wedge strikes the adhesive prematurely.
Support Fixture: An adjustable fixture holds and aligns the specimen under the wedge during testing.
Integrator: A mechanical or electronic or computer-based for calculating failure energy.

Bond Fixture: Fixture with temperature- and pressure-controlled platens for bonding test assemblies per the adhesive manufacturer's instructions.
Test Procedure:
The ASTM D5041 test can be performed on any testing machine with a drive mechanism capable of imparting a constant and controlled velocity to a movable crosshead member. The specimen comprises two flat plates bonded by an intermediate adhesive layer. The specimen is fastened vertically onto a steel support baseplate. A stainless steel wedge with a removable tip performs the cleavage. A threaded coupling attaches the wedge base to the movable crosshead member of the testing machine. A notch is provided at the leading edge of the specimen to initiate crack propagation on the sample. The wedge is driven at a specified speed, and the crack propagation is measured.
Specimen size:
Specimens consist of two flat plates bonded with an adhesive layer. The standard size of specimens is 200 mm in length and 25 mm in width, with adherend plates about 2 mm thick.
The ASTM D5041 test method evaluates the fracture strength of adhesives in bonded joints with reliable performance. Controlled cleavage stresses applied to the specimens measure adhesive performance, surface preparation, and overall integrity of the bonded system. This method can quickly reveal a crack that indicates poor surface preparation, thus providing an easy quality check on the adhesive and bonding process. The fracture strength value obtained from this test is an essential parameter in checking the durability and performance of adhesive joints, particularly those used in reinforced plastics applications.
Require More Customized Solutions?