Influence of Process Parameters on the Phenomenon of Stress Cracking during Hot Plate Welding

Abstract

Heating experiments were carried out in order to investigate the significance of the different process parameters on susceptibility to stress cracking. With the help of wetting tests, different crack lengths were generated in the heated sheet and subsequently compared with the various process parameters by means of multiple regression analysis. Another focal point is the estimation of the normal stress difference (|σ _x -σ _y |)at each point of the specimen by means of 2D photoelastic stress analysis. In both cases the marked correlations between the process parameters and the phenomenon of stress cracking are recognisable, and the results can be used to minimise stress cracking.

Keywords

hot plate welding amorphous thermoplastics stress cracks photoelastic stress study

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References

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