WORLDWIDE TRENDS IN FUNCTIONAL GRADIENT MATERIALS RESEARCH-AND-DEVELOPMENT

This review concerns a new class of advanced materials, known as struc tural and functional gradient materials (FGMs), characterized by compo sitional and/or microstructural gradation over macroscopic/microsopic distances. This constitutional gradation can be tailored for specific requirements. The related properties are not only mechanical (static a nd dynamic strength, hardness, wear resistance), but also thermal (hea t conductivity and isolation), chemical (corrosion and oxidation resis tance), etc. These gradients are introduced intentionally and are quan titatively controlled in order to optimize materials properties for us e in real environments by place-to-place control of composition and mi crostructure. A short theoretical description of FGMs, their processin g methods, applications, etc. is presented, with analysis of their cur rent state of development in the world and in Europe in particular. Fu ture possibilities and trends are also discussed in the light of the c oming Third World Symposium on FGMs at Lausanne, Switzerland.