ASTM D1144:99(R2021) pdf free download – Standard Practice for Determining Strength Development of Adhesive Bonds.
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. If the adhesive is cured by heat, heat the specimens at a prcdetcnnincd rate such that a consistent temperature rise is obtained Differences in beating rates will naturally occur between different types of test 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.
6.3 After the curing treatment, allow the specimens to return to room temperature by natural air convection. Preconditioning of the specimens prior to testing is permissible upon agreement between the purchaser and the manufacturer. Altering the manner in which the cured specimens arc to be returned to room temperature also is permissible, provided the method is agreeable to the purchaser and manufacturer. Room temperature-curing adhesives are allowed to cure for specific time intervals at a temperature of 22 ± 3°C (72 ± 6°F). Cure time is measured from the initial assembly and clamping of test specimens. If the test adhesive has an unusual cure mechanism. or does not adapt to conventional assembly and test methods. use a test procedure agreed upon between the manufacturer and the purchaser. Develop this procedure to adhere as closely as possible to those outlined in this practice.
7.2 After a specified tint, remove clamps and determine if the bond has developed handling strengtfr The initial test time is longer than expected to deselop handling strength. In subsequent tests, shorten the intervals such that the minimum time to develop handling strength esentually is detennined.
7.3 In testing parts for handling strength. load specimens axially. torsionally. or in cleavage, to ensure that the blocking strength of cIte adhesise is not mistaken for handling strength. Once the ininirnuni time has been &tennined. repeat the test a minimum of three times to ensure its accuracy. rn ajiesive types where tiittutr time is irrelevant or too short to test. exclude this test at the agicenrnt of the manufacturer and purchaser.
7.4 Test the specimens as described in the selected appro’ priate ASTM test method, Test heat-cured specimens immediately after reaching room temperature. Room temperature- cured specimens are tested immediately after the specified cure tint has elapsed.
8. Report
11.1 Report the follossing:
8.1.1 Complete identification of the adhesive tested, including type. source, manufacturer’s code number, lot number, form, and actisater.
8.1.2 Complete identification of the adherend used, its type. thickness, method of cleaning, and preparation of surface prior to bonding.
8.S Standard test method used.
8.1.4 Application and bonding conditions used in preparing the specimens,
8,1.5 Cure procedure used for specimens prior to testing.
8.1.6 Fisturing time to the nearest standard unit of time ts.econd, minute. bout),
8.1.7 Fisture time and cure speed data as actual test values. sersus tesi time, to the nearest standard unit of time,
8.1.8 Number of specimens tested, and
8,1.9 Number ofloints represented.