ASTM D4562 Adhesives Shear Strength Using Pin-and-Collar Specimen

Scope:

The shear strength of an adhesive characterizes its resistance to sliding forces that induce failure of the adhesive bond between adherend materials. The shear strength of an adhesive bond depends on the adherend materials, the adhesive, preparation of surfaces, degree of cure and environmental conditions. The test method ASTM D4562 is applicable to measurement of the adhesive shear strength of curing liquid adhesives applied to cylindrical surfaces that slide with respect to each other. The measured shear strength helps in selection and quality control of adhesives used for locking or sealing threaded fasteners and retaining cylindrical assemblies. For example, thread locking and sealing adhesives are applied on threads of nuts and bolts to prevent their loosening in service from vibrations or shear forces.

Procedure:

The ASTM D4562 adhesive shear strength test is performed on an adhesively bonded pin-and-collar specimen. The test specimen is assembled from a cylindrical pin of specified dimensions surrounded by a clearance-fitted cylindrical collar. The pin and collar used in ASTM D4562 testing are usually of steel though other materials may be used based on the application. The test adhesive is applied to the outer surface of the pin and the inner surface of the collar, ensuring absence of voids, after which the assembly is cured. After curing, the pin-and-collar specimen is placed in a test machine such that the collar is firmly supported in a steel fixture, under a platen. A compressive force is applied by the platen onto the top of the pin. The pin is forced to slide downward through the collar and the required force to shear the adhesive bond is used to calculate the adhesive shear strength. Various shear rates and compressive forces can be studied.

Specimen size:

The ASTM D4592 test specimens must be fabricated for the test. A typical specimen could have a collar with inner diameter 13 mm and outer diameter 25 mm, with height of 10.5 mm. The corresponding pin of about 50 mm height, could have a diameter of 12.5 mm, allowing for a maximum adhesive bond thickness of 0.25mm.  

Result:

The adhesive shear strength is reported in pounds per square inch (psi).

Conclusion:

The test method ASTM D4562 is applicable to measurement of the adhesive shear strength of curing liquid adhesives applied to cylindrical surfaces that slide with respect to each other.