Static Shear Strength

High peel strength with cohesive failure is possible by increasing the 0K/NC0 ratio. At a higher ratio, slight creep is observed at room temperature in the static shear test., 0H/NC0 ratios above 2.0 for Hycar 2103 and 1.8 for Hycar 2106 result in adhesives having incomplete cures with low peel values and poor static shear strength. 

Figure 2. Static shear strength values for adhesive joints in deteriorated Doug-las-Jir made with AYAT, Acryloid B72, Butvar B98, and PVA emulsion ""white glue Key P, polar solvent N, nonpolar solvent. (Adapted from ref 21).

There are a wide variety of static shear strength tests as shown in Figure 6.19. These various tests differ in the manner of lateral constraint, shearing plane, and whether they are undrained/drained. 

Fatigue is only likely to occur if power is being delivered in shear through the joint line, and it may be avoided by keeping the continuous running load to around 10 per cent of the static shear strength of the adhesive, measured on the joint concerned. This may equate with the UTS value (see Section 2.2.3 and Figure 2.2). 

Figure 8. Comparison of static shear strength of shrink fit IDS (dotted line), cryogenic fit ID29 (dashed line) and press fit ID23 (solid line) specimens.

Part G2 1987 Determination of static shear strength of anaerobic adhesives. 

The fatigue strength of a lap joint loaded to 20 per cent of the static shear strength value is at least one million cycles at 90 Hz. 

The product used to retain bearing races in housings to restrain them from turning, as weii as providing axial location, is Bearing Fit 641. Its static shear strength is 7 to 16 N/mm (1015 to 2320 ibf/in2). 

For assembiing and permanently retaining cylindricai machine components there is Retainer 601 with static shear strength 16 to 30 N/mm. High Strength Retainer 638 static shear strength 22 to 40 N/mm2. 

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