ASTM B831-19 pdf download.Standard Test Method for Shear Testing of Thin Aluminum Alloy Products.
3. Terminology
3.1 Definitions—The definitions of terms relating to shear testing in Terminology E6 are applicable to the terms used in this test method.
4. Summary of Test Method
4.1 This test method consists of subjecting a full thickness or machined rectangular test specimen to single shear force to failure in a test fixture using a tension testing machine. The shear strength is calculated from the maximum force required to fracture the specimen.
5. Significance and Use
5.1 The intent of this test method is to provide a means of measuring the ultimate shear strength of thin aluminum alloy wrought and cast products. It is recognized that the loading conditions developed by this test method, and by most others, are not ideal in that they do not strictly satisfy the definitions ofpure shear. However, rarely do pure shear conditions exist in structures. N OTE 1—Results from this test method are not interchangeable with results from Test Methods B565 and B769. Shear strengths obtained by this test method have been shown to differ from values determined with other methods. 3
6. Apparatus
6.1 Testing Machines—The testing machines shall conform to the requirements ofPractice E4. The maximum force used to determine the shear strength shall be within the verified force range of the testing machine as defined in Practice E4.
6.2 Loading Device: 6.2.1 The device for applying force to the specimen from the testing machine shall be a clevis of the type shown in Fig. 1 and shall be made of a hardened steel.
7. Test Specimens
7.1 The specimen size shall be 1.5 in. (38.1 mm) wide by 4.5 in. (114 mm) long. The specimen geometry is shown in Fig. 2. The specimen thickness shall be the full product thickness for a product thickness of 0.250 in. (6.35 mm) or less. For a product thickness greater than 0.250 in. (6.35 mm), the specimen shall be machined to a thickness of 0.250 in. (6.35 mm) by machining equal amounts from each side of the product. The minimum specimen thickness that can be reason- ably tested will be dictated by the material’s ability to resist buckling around the pin hole area during testing.
7.2 The test area to be sheared shall be centered within 0.001 in. (0.025 mm) of the load line of the specimen. 7.3 Measure and record the thickness (t) and length (L) of the area to be sheared. Measurements shall be made as follows: 7.3.1 Measurement of the specimen thickness shall be made at a location between the two slots machined into the specimen. Measurement of the length of the shear area shall be between the ends of the slots machined into the specimen, Fig. 2. For dimensions 0.200 in. (5.1 mm) and over, measure to the nearest 0.001 in. (0.025 mm). For dimensions less than 0.200 in. (5.1 mm) and not less than 0.100 in. (2.5 mm), measure to the nearest 0.0005 in. (0.013 mm). For dimensions less than 0.100 in. (2.5 mm), measure to the nearest 0.0001 in. (0.0025 mm). 7.4 All machined surfaces in the test area shall have a surface finish of 32 µin. (0.80 µm) R a or less.ASTM B831 pdf download.