Description: BONDING DESIGN GUIDETwo of the major factors influencing the design of lap joints is the magnitude and direction of the load that the joint must bear. Most adhesives used for bonding flat surfaces are relatively rigid, strong in shear, and not so strong in peel or cleavage. Thus by designing the joint so that the adhesive is in shear, the effect of peel or cleavage stress is minimized. Lap shear joints can be affected shear concentration when the adherents yield. A common lap shear joint “A” in Figure 1-2 tends to deflect (yield) under stress and aligns itself to a shape resembling “B”. Thus, instead of a simple shear stress, the tension effect at edges 1 and 2 creates a peeling stress because a high proportion of the load is carried at the edges of the lap. Figure 1-3 illustrates several joint designs. Some show how the problem of substrate yield can be minimized, and others show the strengths and weaknesses in various bonded joints.GENERAL BONDING DESIGN AND GUIDELINE SURFACE PREPARATION OF VARIOUS SUBSTRATES FOR BONDING OR COATING In virtually every application the quality of the bond between the resin system and the surface to which it is applied is improved if the surface is clean and dry. This is particularly true of adhesive applications where stress will be applied to the cured bond line. It is also true where protective coatings are used. The following surface preparation procedures are recommended. METALS1. Degrease – Wipe faying surfaces with Methyl Ethyl Ketone (MEK) to remove all oil, dirt, and grease. 2. Etch – For optimum results, metal parts should be immersed in a chromic acid bath solution consisting of:Sodium dichromate – 4 parts by weightSulfuric acid – 10 parts by weightDistilled Water – 30 parts by weightThe solution should be held at a temperature of 160°F (71°C), and the parts left immersed for 5 to 7 minutes. 3. Rinse – remove metal parts from etching bath and rinse in clean cold water (de-ionized water is recommended). If thoroughly clean, metal surfaces so treated will hold a thin film of water. 4. Dry – To accelerate drying, items to be bonded can be placed in an air-circulating oven. ALTERNATE PROCEDURE1. Degrease, scour and dry – Often etching as outlined above is not practical. The metal surfaces may be cleaned by degreasing as noted above, scouring with an alkaline cleanser followed by rinsing and drying. 2. Degrease and dry – Degrease the surface as noted above, sand or sandblast the surface lightly but thoroughly. Rinse with acetone or Methyl Ethyl Ketone (MEK), and dryGLASS1. Degrease – With MEK as above, or with a strong boiling solution of a good grade household detergent. 2. Etch – For optimum results, degreasing can be followed with the chromic acid bath outlined above. WOOD1. Sand – Bonding surfaces should be sanded lightly, but thoroughly to remove all external contamination. 2. Clean – Carefully remove all dust, or particles of wood from sanded areas. A stiff and clean brush or compressed air can be used. PLASTIC1. Clean – Remove all dirt, oil, or other surface contaminates with soap and water, followed by thorough rinsing and allow to dry. A solvent that does not have a detrimental effect may also be used. 2. Sand – Surfaces to be bonded should be sanded lightly, but thoroughly to remove surface sheen. 3. Clean – Carefully remove all dust or particles of plastic from the sanded area. A clean brush, lint-free cloth, or compressed air may be used. Modified Surface Ideal For Bonding Flame Treating Of Plastic To Improve AdhesionObtaining adequate bond strength when bonding plastic-to-plastic substrates or plastic to dissimilar substrates is often a challenge for epoxy bonding In general plastic surfaces demonstrates poor ‘wettability’ or the ability of a liquid to form a continuous film. These types of substrates or are called LSE or Low Surface Energy substrates and in general, most thermoplastic surfaces fall within this category. Teflon or its generic name PTFE and other polyethylene derivatives such as HDPE, LDPE, UHMW and olefinic-based plastics demonstrate poor liquid wettability due to its low surface energy. To create a viable bondable surface condition to these types of plastics, it must be surface treated by creating a superficial oxidized surface to increase its dynamic surface tension. Various types of physical treatment can be used to increase the surface energy of plastics, mostly through oxidation of the superficial layer. Flame treatment is the most widely used and cost-effective pre-treatment for polyethylene (HDPE, LDPE, UHMW) and polyolefin-based plastics prior to polymer bonding or printing. The resulting change of the surface by creating an oxidized layer onto the substrate greatly improves the ability of liquids wet-out the surface thus creating a strong adhesive bond between the surface and the coating. A Flame Treating process consists of exposing the surface to a suitable oxidizing flame for a period in the range 0.2 to 3.0 seconds. This treatment brings about a change to the polymer surface that increases its surface energy allowing fluids to effectively wet-out the surface and permits a strong adhesive molecular and mechanical bond. UHMW Sheets Flame Treated- Microscopic Surface Comparison FLAME TREATING USING A COMMERCIALLY AVAILABLE PROPANE TORCH Adjust the propane torch so that a low oxygen burning flame is achieved and pass over the area to be treated several times until a slight haze is noticed on the surface of the substrate. Note the fluid behavior on the flame treated area demonstrating improved substrate wetting thus making adhesion possible for polymers such as adhesives and inks. Modified Surface Ideal For Bonding DON'T FORGET OUR EPOXY MIXING KITEVERYTHING YOU NEED TO MEASURE, MIX, DISPENSE OR APPLY THE EPOXY RESIN Click The Link To Add To Order https://www.ebay.com/itm/222623932456 Proportioning the correct amount is equally as important to attain the intended cured properties of the resin system. The container in which the epoxy and curing agent is mixed is an important consideration when mixing an epoxy resin system. The container must withstand the tenacity of the chemical and must be free of contamination. Most epoxy curing agent has a degree of corrosivity, as a general practice, protective gloves should be worn when handling chemicals of the same nature. MIXING KIT CONTENTS 1 Each Digital Scale -Durable, Accurate Up To 2000.0 Grams 4 Each 32-ounce (1 Quart) Clear HDPE Plastic Mix Cups 4 Each 16-ounce (1 Pint) Clear HDPE Plastic Mix Cups 5 Pairs One Size Fits All Powder-Free Latex Gloves 2 Each Graduated Syringes Wooden Stir Sticks Foam Brush IMPORTANT NOTICE Your purchase constitutes the acceptance of this disclaimer. Please review before purchasing this product. The user should thoroughly test any proposed use of this product and independently conclude the satisfactory performance in the application. Likewise, if the manner in which this product is used requires government approval or clearance, the user must obtain said approval. The information contained herein is based on data believed to be accurate at the time of publication. Data and parameters cited have been obtained through published information, PolymerProducts and Polymer Composites Inc. laboratories using materials under controlled conditions. Data of this type should not be used for a specification for fabrication and design. It is the user's responsibility to determine this Composites fitness for use. There is no warranty of merchantability for fitness of use, nor any other express implied warranty. The user's exclusive remedy and the manufacturer's liability are limited to refund of the purchase price or replacement of the product within the agreed warranty period. PolymerProducts and its direct representative will not be liable for incidental or consequential damages of any kind. Determination of the suitability of any kind of information or product for the use contemplated by the user, the manner of that use and whether there is any infringement of patents is the sole liability of the user.
Price: 33.3 USD
Location: Ontario, California
End Time: 2023-09-27T19:43:59.000Z
Shipping Cost: 0.72 USD
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Restocking Fee: No
Return shipping will be paid by: Buyer
All returns accepted: Returns Accepted
Item must be returned within: 30 Days
Refund will be given as: Money Back
Model: MAX CLR FAST A/B
Country/Region of Manufacture: United States
Type: EPOXY RESIN SYSTEM
MPN: MAXCLRFAST24OZ
Brand: MAX EPOXY RESIN SYSTEM
