BS ISO 22841:2021 pdf download.Composites and reinforcements fibres Carbon fibre reinforced plastics(CFRPs) and metal assemblies Determination of the tensile lap-shear strength.
BS ISO 22841 specifies a method for determining the lap-shear strength of the adhesive joint between carbon fibre-reinforced plastics (CFRPs) and metal adherends, using a standard specimen loaded in tension and under specified conditions of preparation, conditioning and testing. This method is intended for assessing the suitability of adhesives to be used for bonding a carbon fibre reinforced plastic (CFRPs) to a metal.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of BS ISO 22841. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 291. Plastics — Standard atmospheres for conditioning and testing
ISO 472. Plastics — Vocabulary
Adhesive lap-shear bond strength is determined by stressing a single-overlap joint between a CFRP and a metal adherend in shear by the application of a tensile force parallel to the bond area along the major axis of the specimen.
NOTE Single-lap specimens are economical, practical and easy to make. They are the most widely used specimens for development, evaluation and comparative studies involving adhesives and bonded products, including manufacturing quality control.
7 Preparation of test panels
Cut the metal and CFRP to suitable sizes and assemble in a group of two sheets, taking one from each material.
Prepare the adhesive in accordance with the procedure specified by the manufacturer of the adhesive.
The surface to be bonded may or may not be abraded, as agreed between the interested parties. Apply the adhesive to the metal or CFRP as specified by the manufacturer of the adhesive. After the specified time has elapsed, assemble the metal and CFRP into two-ply panels as described in Clause 6. Then press the panel under the specified conditions. Cure time and conditions shall be those specified by the manufacturer of the adhesive or as agreed between client and testing agency and have to be recorded.
9 Preparation of test specimens
Cut the test specimens as shown in Figure 1, taking care that a margin to exclude manufacturing edge effects is removed first. This is accomplished by first cutting the notches to the proper width, depth and location in the test panel, using a hollow-ground grooving saw or any other method that will give equally satisfactory results. Notch the specimens as shown in Figures 1 and 2. The notch of the two-layer specimen shall go as far as the adhesive line and care shall be taken that the ply is cut completely. When the panel has been notched, cut the individual specimens from the panel. Number them consecutively from one end of the panel to the other and identify them with regard to their origin in the panel. Select the specimens to be tested so that an even and equal number of specimens is taken from each test panel. The dimensions of the adhesive shear area as machined shall be reported.BS-ISO-22841-2021