Compound materials by PM-HIP

Abstract

There are many applications where compound materials can be of interest, for example when different properties are needed in different parts of a component. Compound materials can be produced by hot isostatic pressing (HIP) of powder metallurgical materials. One aspect that should be considered in the design is the quality of the interface between the two different material compositions. Diffusion during HIP can cause formation of brittle phases in the interface or deteriorate properties by diffusion of alloying elements. The present work shows results from a study where different steel types were joined (quench and temper steel/air hardening steel/bearing steel with a tool steel/corrosion resistant martensitic steel). The evaluation was performed by computational predictions and by small scale HIP experiments that were evaluated by microstructure analysis and chemical analysis.

Keywords:

• Functional gradient materials
• HIP
• Diffusion
• Tool steels
• Quench and tempered steels
• Bearings
• Corrosion resistant steels

Acknowledgements

We would like to thank F. Sandberg from Erasteel Kloster AB for providing the gas atomised powders needed for the present study and for active participation in the selection of materials. This work is part of a project financed through the Swedish Wind Power Technology Centre (SWPTC). The SWPTC is a research centre for design of wind turbines. The purpose of the centre is to support the Swedish industry with knowledge of design techniques as well as maintenance in the field of wind power. The centre is funded by the Swedish Energy Agency, Chalmers University of Technology as well as academic and industrial partners.