Strength of Adhesion Bonds

ISO 9653 1998 Adhesives - Test method for shear impact strength of adhesive bonds ISO 9664 1993 Adhesives - Test methods for fatigue properties of structural adhesives in tensile shear... 

ISO 11003-1 2001 Adhesives - Determination of shear behaviour of structural adhesives -Part 1 Torsion test method using butt-bonded hollow cylinders ISO 11003-2 2001 Adhesives - Determination of shear behaviour of structural adhesives -Part 2 Tensile test method using thick adherents ISO 13445 2003 Adhesives - Determination of shear strength of adhesive bonds between rigid substrates by the block-shear method... 

The best approach to achieving good performance in bonded joints is to select the proper adhesive, design the joint properly for the specific application, and maintain rigid process control. One disadvantage in the use of adhesives is the absence of good non-destructive tests to determine the strength of adhesive-bonded joints in a wide variety of ord applications... 

Relates the force necessary to separate two surfaces to the adhesive bond strength and is often used to calculate fracture strength of adhesive bonds [111]... 

Test Method for Resistance of Adhesive Bonds to Chemical Reagents Test Method for Applied Weight per Unit Area of Liquid Adhesive Test Method for Applied Weight per Unit Area of Liquid Adhesive Test Method for Peel or Stripping Strength of Adhesive Bonds Practice for Exposure of Adhesive Specimens to Artificial (Carbon Arc Type) and Natural Light... 

Test Method for Impact Strength of Adhesive Bonds Test Method for Tensile Properties of Adhesive Bonds Test Methods for Pressure Sensitive Adhesive Coated Tapes Used for Electrical and Electronic Applications... 

D 1184 Test Method for Flexural Strength of Adhesive Bonded Laminated Assemblies... 

D 3163 Test Method for Determining the Strength of Adhesively Bonded Rigid Plastic... 

D 4501 Test Method for Shear Strength of Adhesive Bonds Between Rigid Substrates... 

ISO 9653 1991 Test method for shear impact strength of adhesive bond. 

The results in Figure 7 show that the strength of adhesive bond between the ferritic steel sample and boiler deposit increased exponentially with temperature in the range of 775 to 900 K. Similar results were obtained by Moza et al. (34) who used a droplet technique to measure the adhesive bond of coal ash slag on a ferritic steel target in the temperature range of 700 to 950 K. 

Table 7.3. Peel Strength of Adhesive Bonded Fluoropolymers ...

Weld Strength - Strength of a welded plastic part at the seam that has been welded is called weld strength. It is measured by methods similar to those for measuring the strength of adhesive bonds. See dl ,o Adhesive Bond Strength. 

USSR GOST 23.2o3-78 "Method of Measuring Strength of Adhesive Bonds for Rubbed Solids Standards Publishers, Moscow, 1978. 

It can be seen from Fig. 3.9 that the strength of adhesive bonds of PVB-A1 determined by endurance in the electrolyte by the peeling method is considerably higher in coatings formed in an electric field and whose volume charge field is directed from the coating to the substrate. 

One of the simplest peel tests to conduct is the 180° peel test described in ASTM 903, Standard Test Method for Peel or Stripping Strength of Adhesive Bonds. In this test, one adherend is much more flexible than the other, so that upon gripping and pulling the two unbonded ends, the sample assumes the configuration shown in Fig. 8d. 

Hart-Smith U. Effects of flaws and porosity on strength of adhesive-bonded joints. Douglas Aircraft Co 1981. report DP 7388. 

The reason for the lack of concordance between the theoretically and experimentally determined values of the adhesion strength lies in the fact that the process of achieving high adhesion strength is hindered by a number of phenomena that accompany the formation of adhesive-bonded joints. These factors that decrease the strength of adhesive-bonded joints can be divided into two groups ... 

Figure 1.2 Effect of residual MMA on the strength of adhesive-bonded joints (1) before and (2) after vacuum treatment and (3) on the internal stresses <7,5 in the adhesive layer.

In our view, the failure to determine correlation between the thermodynamic characteristics of adhesion and the strength of adhesive-bonded joints lies in the fact that what was being studied was the relationship of the initial compoimd properties (in the hquid state) with the strength of joints in which the adhesive was in the cured state. In addition to ignoring the essential differences of the cured adhesive from the initial liquid, there was no accoimt for irregularity of the process of formation of adhesive-bonded joints itself, which means that the most favorable adhesive structure (from the thermodynamic point of view) is not realized for kinetic reasons. The necessity for accounting for these factors has been established in previous sections. 

When adhesives are applied for the repair of ships, blowholes in pipelines, and other objects, the adhesive interlayers are frequently subjected to impact loads under tension this occurs, for example, in hydraulic impacts on pipelines, in ships during mooring, and so on. In this context it is interesting to investigate the effect of the modifying additives in Sprut-5M upon the strength of adhesive-bonded joints under tensile impact loads. 

The additional introduction of the fluorinated alcohol into the adhesive enhances its water resistance. Thus, the adhesion strength of adhesive-bonded joints of steel using Sprut-4 adhesive does not change significantly over time even with many years in water. 

The strength of adhesive-bonded joints under the combined effect of tangential and normal stresses at 20, 40, 60, 90, and 100 days after cementing of St3 steel is displayed in Fig. 3.9 as surface stress plotted in coordinates cr—Taj time. Surface I characterizes the extreme stresses of the joints using VAK adhesive surface II is the same without addition of ATG to the adhesive. 

Let us consider the adhesion properties of ERC. The mechanism of the effect of the low-molecular-weight additives on the properties of the polymers in block has been studied in detail, though their effect on the strength of adhesive-bonded joints has not yet been studied in sufficient detail. 

Note that in all cases the initial strength is reestablished after the adhesive-bonded joint is dried. Thus, the drop in strength of adhesive-bonded joints operated in water is explained mainly by diffusion of water at the adhesive-substrate interface. Methods that increase water resistance decrease the rate of water diffusion along the interface, although it still takes place. Increase in the rate seems to be caused by both adsorption and diffusion mechanisms of the medium. 

Influence of the Molecular Size of the Filler Surface Modifier on the Strength of Adhesive Bonds with Solid Substrates and the Molecular Mobility of the Filled Polyurethane... 

Figure 2.22 Dependence of the adhesion strength of adhesive-bonded joints on the difference of the interphase and surface tensions of adhesive.

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