Application of tribological material data

In today's world, increasingly high-performance and reliable products have to be developed in ever shorter timeframes to guarantee a company's competitiveness. Environmental laws and lists of prohibited substances/materials, as well as price trends and security of supply, mean that many materials have to be redesigned. In addition, the need to lighten parts for economic and/or ecological reasons is becoming increasingly important. In this context, the most successful engineer will be the one with the greatest experience in the field of materials, coatings and lubricants. This experience of a specialist in both materials and tribology is most often virtual. This is because a large proportion of technical failures start at the contact surface of materials in relative motion, and the tribological behavior of materials and the performance of lubricants or coatings in sliding or rolling contact ultimately determine the quality of the initial design. Engineers therefore need rapid access to the latest experimental knowledge in tribology.

Every year, tens of thousands of tribological results are obtained and published, but there are two major problems:

• Access to them is still difficult, expensive and time-consuming;

• how can we make the most of this data when designing a product, a machine or using a material?

Indeed, most of this vast tribological capital remains scattered across a multitude of industrial or university laboratories. Moreover, the diversity of experimental procedures used and modes of interpretation makes it difficult, if not impossible, to compare the results obtained by teams of tribologists. In addition, materials developers, oil companies and end-users speak different languages and have different interests and objectives. As a result, the reader is often not in a position to appreciate whether the tribological results and properties announced for a pair of dry friction materials or a lubricant in a given contact can help him solve his specific problem.

The aim of this text is twofold:

• describe how a tribological database should be organized ;

• use examples to illustrate how such a database can be used to design a tribosystem.

Tribosystem design presupposes the organization of a tribological database, then its use to predict the behavior of the tribosystem under study. It should be noted that this use, like the design of a database, is based on a prior theoretical analysis of what a tribosystem is:

• to identify key system parameters;

• to establish test procedures;

• ...