What is ASTM D1002?

What is ASTM D1002?

ASTM D1002 describes the procedure for evaluating the shear strength of adhesives used for bonding metals. Adhesive testing is critical for understanding the relative strength of different materials, as well as identifying the effects of environmental conditions and aging on the strength and durability of a bond.

What is single lap shear Test?

Single-lap shear tests are used for plates to check adhesion between the adhesive and the FRP, and to give an indication of the mechanical properties of the cured adhesive (expressed as average shear strength). The test is therefore a check both on surface preparation of the FRP and on correct mixing and curing.

How do you perform a lap shear test?

Test Procedure:

1. Measure the amount of shear area in square inches or square centimeters.
2. Load each end of the specimen in the tensile grips.
3. Apply a force at a controlled rate to the specimen until it breaks and record the maximum force and type of joint failure.

What is lap shear?

Lap shear strength testing measures the ability of a material to withstand stresses set in a plane, where the exerted shear force is moving the two substrates in opposite directions. It is one of the most common stresses that a bonded joint can face during service, especially in structural bonding applications.

What is ASTM D903?

ASTM D903 is a common tensile test used to evaluate the peel or stripping characteristics of adhesively bonded materials used in a wide variety of applications in an even wider range of industries. Some examples of materials tested to ASTM D903 are plastic films, adhesive labels, and waterproofing materials.

What is meant by the term shear force when applied to materials used in vehicle manufacture and construction?

A force acting in a direction parallel to a surface or to a planar cross section of a body, as for example the pressure of air along the front of an airplane wing. Shear forces often result in shear strain. Resistance to such forces in a fluid is linked to its viscosity. Also called shearing force.

What is peel test?

Peel tests measure the strength of the bond between a substrate and the material being peeled off (known as the adherend). This peel strength is expressed as the load required to separate the adherend from the substrate, per unit width of the bond.

What is single lap joint?

Single-lap joints are a widely-used and relatively strong and simple way joining two materials via an overlapping bond. With the growing use of composite materials in modern design practices, the need to join increasingly dissimilar materials has arisen.

What is the lap shear strength?

Lap shear strength is a measure of how much shear force can be exerted on a lap joint before failure occurs. Lap shear strength is often tested during joining process qualification or material validation to avoid a future failure.

How do you test skin strength?

Based on the practical consideration of the adhesive bond, peel tests are usually determined at peel angles θ of 90° or 180° or in a T-peel configuration. The peel strength is measured as the amount of force acting on the width of the bonding surface when peeled at a constant velocity.

How do you test adhesive?

To measure adhesion, tape is applied to a stainless steel panel. The tape is then removed. The force required to remove (or peel) the tape determines its adhesion level. The force is measured in ounces per one inch of tape.

What is meant by single shear and double shear of riveted joint?

The average shear stress in the plane is τave= F/A. This joint is said to be in single shear. If the plates, which are connected by a rivet as shown in the following figure, are subjected to tension forces, shear stresses will develop in the rivet. This joint is said to be in double shear.

Which is the best lap shear test for metal?

There are a variety of ASTM single-lap-joint shear tests including ASTM D-1002 which specifies lap shear for metal to metal, ASTM D-3163 for plastics joints, and ASTM D-5868 for fiber reinforced plastics (FRP) against itself or metal. Two metal plates are bonded together with adhesive and cured as specified.

How big should a lap shear specimen be?

The recommended lap shear specimen is 25.4 mm (1”) wide, with an overlap of 12.7 mm (0.5”). The recommended metal thickness is 1.62 mm (0.064”) and the overall length of the bonded specimen should be 177.8 mm (7”).

What are the factors that influence the lap shear test?

Many factors influence the single lap shear test, which are usually not taken into consideration. Shear stress is not constant along the overlap region, presenting stress concentration at the extremities. The stress concentration intensity depends on factors like: substrate/adhesive thickness and mechanical properties.

How are metal plates bonded for Lap shear?

Two metal plates are bonded together with adhesive and cured as specified. The assembly is then cut into uniform width lap shear specimens. The test specimens are placed in the grips of a universal testing machine and pulled at 1.3 mm/min (0.05 in/min) until rupture occurs.