7236

7236 3M | Alldatasheet

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Two Part Structural Adhesive Scotch1Weld™ 7236 B/A 3M™ Scotch1Weld™ 7236 B/A Two Part Structural Adhesive Product Description 3M ™ Scotch-Weld ™ Structural Epoxy Adhesive 7236 B/A is a two component epoxy adhesive which cures at room temperature or with mild heat to form a strong, impact resistant structural bond. It has an excellent adhesion to a wide variety of substrates such as metals, ceramics and plastics, incl. GFRP and CFRP. Once cured it provides extremly high mechanical strength over a wide temperature range, with excellent resistance to harsh environments and chemicals, commonly encountered in aerospace applications. The product is available in a white and a black version Key Features

• Toughened system providing extremely high mechanical strength
• Wide service temperature range
• Excellent environmental resistance
• Full room temperature processing Product Characterization The following technical information and data should be considered representative or typical only and should not be used for specification purpose General Properties Part B Part A SW 7236 B/A white Off1white White Colour SW 7236 B/A black Off1white Black Base Modified epoxy Modified amine Consistency Thixotropic paste Slight gel Density 1.18 g / cm³ 1.05 g / cm³ Solids 100 % 100 % Viscosity (a) 800 – 2000 Pas 10 – 25 Pas Mix ratio by weight (by volume) 100 : 27 (100 : 31) Work life (b) at 23 ± 2 °C / Open time > 60 minutes / 20 minutes Handling strength (c) 314 hours Strength build1up at 23 ± 2 °C 25% 50% 75% 100% 0h 2d 4d 6d 8d 10d 12d 14d Full cure cycle 14 days at room temperature Packaging Cans and pails (a) Brookfield RVF Spindle 7,2 Upm (b) 50 g of mixed adhesive (c) Time to reach 1 MPa Shear Strength Technical Data Sheet Aerospace

Two Part Structural Adhesive Scotch1Weld™ 7236 B/A Page 2 of 3 Product Performance The following data show typical values obtained with Scotch-Weld™ 7236 B/A on unprimed, sulfochromic etched, 2024 T3 aluminium. The samples have been cured for 15 days at room temperature, if not stated otherwise. To control the bond line thickness, approximately 1 wt. % of glass beads, 90 – 150 µm diameter were added to the adhesive. Mechanical Properties Test Temperature Cured for 15 days at 23 °C Cured for 2 hours at 65 °C 155 °C 28 MPa 36 MPa 23 °C 39 MPa 42 MPa 80 °C 22 MPa 25 MPa Overlap Shear Strength EN 224311 120 °C 3,5 MPa 4 MPa 23 °C 85 N / 25 mm 107 N / 25 mm Floating Roller Peel Strength EN 224312 80 °C 1 1 Impact Resistance AFNOR NF 761115 23 °C 30,3 kJ / m² 31,3 kJ / m² (d) Substrate Failure Environmental Ageing The following data show typical values obtained with Scotch-Weld 7236 B/A after 750 hours exposure to different media and environments to determine the aging resistance. The samples have been cured for 15 days at room temperature. Mechanical Properties Environment Test Temperature Results Gasoline super at 23 ± 2 °C 23 °C 36 MPa Engine oil (20W40) 23 ± 2 °C 23 °C 37 MPa Hydraulic fluid skydrol 500B at 23 ± 2 °C 23 °C 38 MPa JP4 fluid at 23 ± 2 °C 23 °C 32 MPa Hot / Wet 70 °C, ≥ 95% R.H. 23 °C 30 MPa Overlap Shear Strength EN 224311 Dry heat at 120 ± 2 °C 23 °C 40 MPa

Two Part Structural Adhesive Scotch Weld 7236 B/A Page 3 of 3 Handling, Application, Storage Precautionary Information Refer to product label and Material Safety Data Sheet (MSDS) for health and safety information before using this product. For MSDS visit our website www.3M.com/msds . Instructions for use While this information is provided as general application guideline based upon typical conditions, it is recognized that no two applications are identical due to, among other things, differing assemblies, methods of heat and pressure application, production equipment and other limitations. It is therefore suggested that experiments be run, within the actual constrains imposed to determine optimum conditions for your specific application and to determine suitability of product for particular intended use. Process step Instruction Surface preparation The strength and durability of a bonded joint are dependent on proper treatment of the surface to be bonded. An acclimated, thoroughly cleaned, dry, grease1free surface is essential for maximum performance. Cleaning methods which will produce a break free water film on metal surfaces are generally satisfactory. At the very least, joint surfaces should be cleaned with a good proprietary degreasing agent and mechanically 3M 08984 Adhesive Cleaner. Optimum processing temperature for substrates and adhesive is around room temperature of 23 °C. Application This product consists of two parts. Combine Part B and Part A in a separate container just prior to application in the proportions specified. Note : Mix ratio deviations above +/1 5 % have significant influence on material performance. Mix both components thoroughly until a uniform colour is obtained. Important: Be careful when mixing quantities larger than 100g, because exothermic reaction may occur. Apply adhesive to parts to be bonded before the work life expires, e.g. by spatula. Note: Work life depends to some extent on mixed quantity and the shape of the container. Use of a shallow container will minimize the quantity impact. In order to obtain optimum mechanical performance, the joint components should be assembled and clamped as soon as the adhesive has been applied and before end of the open time. A fixation of the joint and an even contact pressure throughout the joint area during cure will ensure optimum performance. Maximum shear strength is obtained with 0.10 – 0.20 mm bond line thickness. Close the containers after use to protect the material against humidity. Curing Once mixed, Scotch1Weld™ 7236 B/A will gel in 2 hours, build up handling strength in 314 hours and fully cure within 14 days at room temperature. Note: Lower temperature will slow down the reaction times. Curing time can be accelerated by mild heat. Following times and temperatures will result in a full cure: /square4 14 days at 23 ± 2 °C /square4 2 hours at 65 ± 2 °C Note: The curing temperature may have influence on the final product performance. Cleaning Excess uncured adhesive can be cleaned with ketone type solvents. After cure the adhesive can be removed mechanically. Note : When using solvents, extinguish all ignition sources, including pilot lights, and follow the manufacturer’s precautions and instructions for use. Storage and Handling Store the product at room temperature. Shelf life is 12 months from date of shipment in the original unopened containers. Important notice: All statements, technical information and recommend ations in this data sheet are based on tests 3M bel ieves to be reliable, but the accuracy or completeness of those tests is not guaranteed. All technical data and information should be considered typical or representative only and should not be u sed for specification purposes. Given the variety of factors that affect the use and performance of a 3M produ ct, some of which are uniquely within the user’s kn owledge and control, it is essential that the user evaluate the 3M product before use to determine the suitability of the 3M product for the intended use and method of application. All questions of liability relating to the 3M product are governed by the terms of the sale subject to, where applicable, the prevailing law. Aerospace and Aircraft Maintenance Department European Aerospace Laboratory www.3m.eu/aerospace © 3M 2010. All rights reserved . Reference: 122