ASTM D5041-98(R2019) pdf free download

ASTM D5041-98(R2019) pdf free download.Standard Test Method for Fracture Strength in Cleavage of Adhesives in Bonded Joints
1. Scope
1.1 This test method covers the determination of fracture strength in cleavage ofadhesive bonds when tested on standard reinforced plastic specimens and under specified conditions of preparation and testing (Note 1). N OTE 1—While this test method is intended for use in reinforced plastic applications, it may be used for measuring fracture properties ofadhesives using other plastic adherends, provided consideration is given to the thickness and should be of equal rigidity to the plastic adherends. 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—Many of the terms used in this test method are defined in Terminology D907. 3.2 Definitions ofTerms Specific to This Standard: 3.2.1 failure initiation energy, E i —the area under the load deflection curve where the first significant load drop occurs after the start of the test, showing the onset of permanent damage to the bonded assembly (see Fig. 1). 3.2.2 failure propagation energy, E p —the area under the load-deflection curve beginning at the failure initiation energy and ending at the catastrophic failure of the bonded assembly. (See Fig. 1). 3.2.3 semirigid—indicates that the adherends shall have such dimensions and physical properties as to permit bending them through any angle of up to 30° without breaking or cracking. 3.2.4 semirigid adherend, n—an adherend that has dimen- sions and physical properties that permit bending at designated test temperature through any angle up to 30° without breaking or cracking. 3.2.5 total energy—failure initiation energy plus failure propagation energy.
4. Significance and Use
4.1 This test method provides a means of measuring the cleavage forces and energies required to fail adhesively bonded reinforced flat bonded specimens. It also offers a semi- quantitative observation of failure mode. 4.2 This test method has found application in screening structural adhesives for bonding reinforced plastics where simple lap shear testing has proven to be inadequate in distinguishing differences between adhesives. 4.3 It is important to note that the test method measures performance properties of the total bonded system (for example, reinforced plastic and adhesive) but will not yield fundamental properties of the adhesive alone.
5. Apparatus
5.1 Testing Machine, any suitable testing machine capable of control of constant-rate-of-crosshead movement and com- prising essentially the following: 5.1.1 Drive Mechanism, a mechanism for imparting to the cross-head movable member, a uniform, controlled velocity with respect to the base (fixed member); this velocity is to be regulated as specified in Section 10. 5.1.2 Load Indicator, a mechanism capable of showing the total compressive load carried by the test specimen. The mechanism is to be essentially free from inertia-lag at the specified rate of testing and indicate the load with an accuracy of 61 % of the maximum indicated value of the test (load). Verify the accuracy of the testing machine at least once a year in accordance with Practices E4. 5.2 Wedge, made of either aluminum or steel with an included angle of 45°. The sides of the wedge are machined smooth with the edge having a radius not to exceed 0.02 mm (0.01 in). N OTE 2—A stainless steel wedge is recommended, has been found to work well, and is very durable. Due to the weight of a steel wedge, the removal of excess metal, which does not adversely affect the stiffness of the wedge, is recommended. 5.3 Removable Tip (Optional)—In some cases, the tip of the traveling wedge will strike the adhesive before catastrophic failure. This phenomenon will lead to grossly distorted test data. Should this be a problem in some adhesively bonded assemblies, a removable tip wedge of the design shown in Fig. 2 is suggested.