Abstract: The aim of the invention is to provide a fluxing agent for soldering components, which creates one or more specific surface characteristics during the soldering process itself, thus obviating the need for the surface treatment process that is conventionally carried out after the soldering process. To achieve this, nanoparticles are added to a base substance.

Abstract: The invention relates to a method for modifying piece surfaces consisting in bringing pieces into contact with at least one type of a modifying agent in such a way that the modification of the surface is carried out.

Abstract: The invention relates to a heat exchanger provided for heating purposes, particularly for a motor vehicle, comprising: a number of parallel pipes, at least one electric heating device (4), which is mounted each time between two adjacent pipes, and comprising a number of fin elements (5) situated between each pair of adjacent pipes and between each heating device (4) and the pipes adjacent thereto. In order to be able to better control the power absorption of the heating devices (4), each heating device (4) comprises two separately controllable heating sections (6, 7). One heating section (6) is placed on one side (8) of the heating device (4) facing one adjacent pipe, whereas the other heating section (7) is placed on an opposite side (9) of the heating device (4) facing the other adjacent pipe.

Abstract: The invention relates to a soldering flux based on potassium fluoroaluminates, wherein the zirconium fluoride and/or titanium fluoride is added to the soldering flux. The invention also relates to a corresponding soldering method.