Increasing bearing life by combining a novel manufacturing bearing steel process with multiscale modelling techniques

This project aims at increasing bearing life by combining a novel manufacturing bearing steel process with multiscale
modelling techniques. The new manufacturing process is based on adding an induction heater to the tundish of a
continuous cast process for bearing steel manufacturing; this will significantly enhance inclusion control and increase
bearing life. The work will be combined with modelling of multiscalar effects associated to bearing fatigue, allowing to
optimise the microstructure for fatigue, and to select optimal processing parameters for alloy processing. The end result will
be computer programmes to aid manufacturers to control bearing steel processing, rules for optimal steel processing,
methods to quantify inclusion content in ultra-clean steels, and understanding of how variations in microstructure and
composition lead to different bearing life."

Outside the academic realm, direct impact of this work can be divided in three spheres of influence. The direct user of this
work would be SKF, who have sponsored the majority of the work that has preceded this proposal. They can employ the
new steel processes for the fabrication of bearings of improved life. The second sphere of influence corresponds to the
group companies related to SKF UTC that have an interest on rolling contact fatigue, bearing steel improvement and
understanding of microstructure evolution under cyclic stresses. These companies include TATA Steel, Rolls-Royce,
Eramet, Aubert et Duval and Ovako. Finally, there are several companies not directly related to SKF UTC to which the
technology can be licensed, or that can adopt some of the computational methods developed in the project. These include
a very large list, but the proposer has a good relationship with, for example, Ascometal, ArecelorMittal and Nippon Steel.
They all produce materials for components subjected to structural fatigue, to which the concepts emerging from this project
can be applied.
Controlling inclusions and predicting the related damage development during rolling contact fatigue can lead to more
durable bearings, rolling components and machinery. This leads to environmental benefits due to enhanced durability of
components, improved reliability and maintenance reductions. Society at large would therefore benefit from this work.
One process optimisation is achieved toward the end of this project (2 years from the start), more durable bearings are
produced and statistics demonstrate life improvement. Benefits for the consumer would probably be appreciated in about 3.5 years, considering the life of certain bearings in constant use is half a year.