ASTM D3164 Shear by Tension Loading
Introduction
The standard test method ASTM D3164 assesses shear strength in adhesive bonds loaded in tension. The tensile load applied perpendicular to the bond line simulates the conditions under which shear stress commonly occurs. This test method has been extensively used in most industries that require structural integrity and performance, such as the aerospace and automotive industries.
Scope
Shear by Tension Loading ASTM D3164 generates shear strength data for joints. This test is also applicable for comparing adhesive treatments or analyzing surface treatments of plastics. Shear is defined as a sliding failure along a flat surface, whereas tension loading is the capacity of a material to resist a pulling force. This test method aims to supplement test methods ASTM D1002 and D3163 and apply their use to single-lap-shear adhesive joints with plastic adhesives. ASTM single-lap-joint shear testing covers ASTM D1002, specifying the apparent shear strength for bonding metals. ASTM D3163 is used for rigid plastic adherents and ASTM D5868 for fiber-reinforced plastic (FRP) adherents.
ASTM D3164 Test Procedure
The ASTM D3164 test procedure is summarized in the table below:
| Steps | Description |
| Step 1: Preparation of the sample | Prepare bonded specimens with equal dimensions and ensure proper adhesive cure per manufacturer’s guidelines. |
| Step 2: Test Fixture Setup | Mount the specimen into the testing fixture, ensuring precise alignment to avoid eccentric loading. |
| Step 3: Calibration of the test machine | Calibrate the test machine to apply tensile force at a uniform rate. |
| Step 4: Application of the load | Apply tensile force perpendicular to the bond line at a specified rate until failure occurs. |
| Step 5: Data recording | This recording should be done for load applied and displacement throughout testing. |
| Step 6: Failure observation | Classify the failure mode (adhesive, cohesive, or substrate failure). |
Sample Size
Shear by Tension Loading ASTM D3164 uses a lap shear sample of 25.4 mm (1 inch) with an overlap of 12.7 mm (0.5 inches). The suggested metal thickness is 1.62 mm (0.064 inches) for the bonded sample, which has an overall length of 177.8 mm (7 inches). The advised thickness of the plastic insert is 0.354 mm (0.010 inches) or less.
Result Analysis
ASTM D3164 tests are usually reported regarding the maximum shear strength of the adhesive bond, obtained by dividing the maximum load applied by the bond area. A more critical analysis of the failure mode is done to ascertain whether a failure has occurred because of the adhesive, cohesive properties of the material, or substrate. This information would allow for the identification of the performance characteristics of the adhesive and its appropriateness for a particular application. It can also be helpful to investigate stress-strain behavior to characterize the adhesive, mechanical properties in tensile loading.
Conclusion
ASTM D3164 provides a reliable method of measuring adhesive bonds’ tensile stress shear strength, providing invaluable information on adhesive selection and quality control. The results will enable the manufacturer to understand the durability of the adhesive and predict the adhesive performance in real situations. In addition, identifying failure modes also allows the improvement of bonding techniques, thereby enhancing product reliability.
FAQs
What is the purpose of ASTM D3164 testing? The test evaluates the shear strength of adhesive bonds under tension loading to assess their performance and reliability.
What materials can be tested using ASTM D3164? Any adhesive-bonded materials, including metals, composites, plastics, and ceramics, can be tested.
What type of loading is applied in this test? A tensile force perpendicular to the adhesive bond line is applied to generate shear stress.
How is shear strength calculated? Shear strength is calculated by dividing the maximum load applied during the test by the bond area.
