Angle and Corner Joints

S Angle and corner joints. A butt joint is the simplest method of bonding two surfaces that meet at an angle. Although the butt joint has good resistance to pure tension... 

Film thickness measurements should not be made close to the edge of a steel surface since the magnetic properties of the steel influence the reading, causing distorted results. It is recommended that measurements be made at least 1 in. away from the edge. Distorted readings can also result from angles, corners, welds, crevices, and joints. Always measure a clean surface, never an oily or dirty one. 

One of the results of the finite-element analysis is that the highest principal stresses in the adhesive layer of a lap joint occur not only near the ends of the bond-line but, more precisely, in the region of the corner of the unloaded adherend. This suggests that it may be possible to increase joint strength by radiusing the corner of the adherend. Adams and Peppiatt (1974) analysed a 0-4 mm radius on the unloaded adherend corner and the maximum principal stress in the spew was shown to be much less than that obtained with a right-angle comer (see Table 2). 

Corner or angle joints (a) simple, (b) sealant bead with bond breaker, (c) sealant bead with backing material, (d) sandwich seal supported, and (e) bead seal supported... 

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