Home>ASTM Standards>ASTM D1144-99(R2021) pdf free download

ASTM D1144-99(R2021) pdf free download

ASTM D1144-99(R2021) pdf free download.Standard Practice for Determining Strength Development of Adhesive Bonds
1. Scope
1.1 This practice covers the determination of the strength development of adhesive bonds when tested on a standard specimen under specified conditions ofpreparation and testing. It is applicable to adhesives in liquid or paste form that require curing at specified conditions of time and temperature or specific substrate preparation. It is intended primarily to be used with metal-to-metal adherends; however, plastics, woods, glass, or combinations of these may be substituted. 1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appro- priate safety, health, and environmental practices and deter- mine the applicability ofregulatory limitations prior to use. 1.4 This international standard was developed in accor- dance with internationally recognized principles on standard- ization established in the Decision on Principles for the Development of International Standards, Guides and Recom- mendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
3. Terminology
3.1 Definitions—Several terms in this practice are defined in accordance with Terminology D907. 3.2 Definitions ofTerms Specific to This Standard: 3.2.1 activator, or accelerator (surface), n—an adhesive curing agent that is applied to a bonding surface for the purpose of affecting or speeding, or both, the cure of an adhesive. 3.2.2 fixture time (set time), n—the shortest time required by an adhesive to develop handling strength such that test speci- mens can be removed from fixtures, unclamped, or handled without stressing the bond, thereby affecting bond strength. 3.2.3 handling strength, n—a low level of strength initially obtained by an adhesive that allows specimens to be handled, moved, or unclamped without causing disruption of the curing process or affecting bond strength.
4. Significance and Use
4.1 This practice contains suggested provisions for report- ing strength values. Any ASTM test method for determining strength properties of adhesive bonds may be used. This practice is not intended to determine the pot or working life of two-component epoxy of similar type adhesives. Refer to Practice D1338. It should be noted that there are adhesives whose testing requires special techniques and whose properties are difficult to reproduce from tester to tester. These variables should be kept in mind when analyzing the data obtained using this practice.
5. Test Specimens
5.1 It is suggested that lap-type shear specimens in accor- dance with Test Method D1002, be used. Other types of test specimens may be used with agreement between the manufac- turer and the purchaser.
6. Preparation of Test Specimens
6.1 Prepare test specimens in accordance with Test Method D1002, or other applicable test method. Prepare the bonding surface by a method mutually agreed upon between the manufacturer and the purchaser. Vapor phase degreasing, grit blasting, hand abrasion, or testing on oiled surfaces are some of the methods that are available. If a surface activator or accelerator is used, apply it in accordance with the instructions of the manufacturer. Use one- or two- surface activation as agreed upon between the manufacturer and the purchaser. Allow assembled specimens to cure at the temperature and period of time prescribed by the manufacturer to develop full strength. This is intended to determine if any post curing of the adhesive occurs that would cause a strength increase and decrease. Bond strength variability could be caused by em- brittlement or a further hardening of the adhesive during the cure cycle. 6.2 In addition, prepare assemblies for curing at the same temperature and time intervals to determine fixture time and 20, 50, and 80 % strength. Ifthe adhesive is cured by heat, heat the specimens at a predetermined rate such that a consistent temperature rise is obtained. Differences in heating rates will naturally occur between different types oftest specimens due to different conductivities. Determine the temperature of the adhesive by means of a properly insulated thermocouple or contact pyrometer placed in the geometric center of the bond area. Bring the adhesive layer to the curing temperature as promptly as possible and start the measurement of curing time when the adhesive has reached the curing temperature.

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