Technical Committee Lubricants
Tribological relevant interactions of soot in the lubricant for diesel engines with lubricant-components and material surfaces of highly stressed engine components
The research project examined the wear-promoting effect of soot, continuing the work of the DGMK 588 project. The main focus was the five model hypotheses collected by Boelter. Different test series were run on a micro tribometer and a pin on disc tribometer. Two sooting plants carried out soot accumulation of fresh oil. The oils, soot, and the surfaces of friction bodies were analyzed in many different ways. With the help of the test results and considerations, th oil aging model and the deactivation model according to DGMK 588 is not always given; however, the model hypothesis is not completely refuted because of this. It was found that wear caused by soot is based on at least two effects: indirectly by impediment of the additive effects and directly on the surfaces of metal (oxide). A test series in which the additive composition of lubricating oils was systematically varied showed that the combination of high concentrations of ZDDP and soot had particularly high conspicious appearance of wear.
The IGF project (15552N) of the Research Association for Petroleum, Natural Gas and Coal was funded by the AiF in the framework of the
of the programme for the promotion of joint industrial research and development (IGF) by the Federal Ministry of Economics and Technology on the basis of a resolution of the German Bundestag.