A COMPUTER KNOWLEDGE-BASED SYSTEM FOR SURFACE COATING AND MATERIAL SELECTION

Because the majority of component failures in service can be attribute d to surface-initiated effects, there is much to be gained by the spec ification of an appropriate surface coating for the working environmen t. Unfortunately, the range of coatings available, and their interacti on with the materials to which they are applied, makes this a task for which considerable expertise is required. In this paper we report pro gress in development of the PRECEPT knowledge-based computer system, w hich is being constructed to aid the engineering designer in making an informed selection of surface coatings and materials to satisfy the d esign and service requirements of a component. In the paper we discuss the strategy for selecting surfaces based on the criteria of resistan ce to wear, fatigue and corrosion as well as the physical properties r equired of the bulk material. Fundamental to the selection process is the concept of a combination; that is, a material and coating consider ed together as a single entity, with unique properties. This has consi derable implications for the selection process, data and knowledge gat hering and the implementation of the system. These points are discusse d together with initial results of user testing the prototype system.