Investigation of a Critical Irradiance Criterion for Minimizing the Cure Time of a PAW Joint

Photo-activated Adhesive Workholding (PAW) technology is used to hold workpieces for manufacturing processes. This paper proposes a critical irradiance criterion that can be used to determine whether a curing light system is capable of curing a PAW adhesive joint at its maximum rate. It describes a series of experiments that were conducted to investigate the plausibility of this criterion for adhesive joints comprised of a commercially available adhesive mixed with various concentrations of carbon black and at varying thicknesses. Lastly, it provides experimental evidence that indicates that the addition of small concentrations of carbon black to a modified acrylic adhesive does not change its asymptotic, maximum strength. Furthermore, adhesive joints that are exposed to radiation that satisfies the critical irradiance criterion cure at a maximum rate. (C) Koninklijke Brill NV, Leiden, 2010