New combinatorial chemistry approach in material science

A new combinatorial approach is proposed. It is based on the preparation of crystallized samples with a progressive composition gradient using the mel ting or floating zone technique. It may be applied to metallic, high refrac tory, and glass materials and allows the rapid elucidation phase constituti on and the variation of physical properties with composition and microstruc ture. The approach may be applied to a broad spectrum of materials and samp les may be quite smaller. Four examples are presented herein: polyphased Al -Co alloys, a single crystal of yttrium oxide codoped by Er3+ and Yb3+, and a glass sample containing SiO2-Al2O3-CaO-Na2O-K2O. This approach constitut es a good and inexpensive experimental method for exploring industrial mate rials and for the theorical prediction of materials of interest. We propose in this paper a new combinatorial approach to materials study th at is based on the preparation of materials with a continuous composition g radient. Samples are prepared by a melting or floating zone technique. On t he same sample, it is possible to describe the phases across a phase diagra m and to determine physical properties-microstructure-thermal heating-compo sition relations for those physical properties that can be measured in situ . Four examples will be given: one concerns the direct reading of phases ac ross a phase diagram, the second shows the possibility of relating the phas e diagram in-situ measurements of selected physical properties, the third d escribes the evolution of a physical property and its dependence on composi tion in a ternary system, and the last corresponds to an easy extension of this approach to higher-order systems.