In-product environmental protection: evaluation of chemical emissions from the spot welding joining technique in the automobile industry Part II. Laboratory pyrolysis measurements with a welding chamber

In the first part of this series we introduced the aim of this work and the methods used for evaluation of chemical emission when using the combined joining technique of weld bonding. In this part of the publication we give detailed information of the influence of some parameters on the formation of BTEX (benzene, toluene, ethylbenzene and xylene), PAH (polycyclic aromatic hydrocarbons) and oxo compounds (aldehydes and ketones). For this purpose, we developed an experimental set up which is a model for the real process. We investigated the following parameters: thickness and surface treatment of applied steel sheets, lubricant, type of adhesive agent and the welding current. We tried to find a correlation between the investigated parameters and the formation of BTEX, PAH and oxo compounds.