| 摘要 |
PURPOSE: To produce a material provided with different properties such as superplasticity and toughness or elastic modulus concurrently by dispersing the first crystal grains having low aspect ratios and the second crystal grains having high aspect radios, both of which consist of a same material, to be in a specified state. CONSTITUTION: This material consists of two kinds of crystal grains, i.e., the first crystal grains 1 having low aspect ratios and the second crystal grains 2 having high aspect ratios, both of which consist of a same material. At this time, any one kind of these crystal grains 1 and 2 is used as the matrix and the other kinds is used as the dispersoid 20 which is dispersed in this matrix and has an island or network structure formed by allowing the crystal grains to combine with each other in the crystal grain groups to produce the objective material having such a composite structure. In the material, e.g. a structure in which the peripheries of islands or the like consisting of the crystal grains 2 that have high aspect ratios and contribute to provide the material with high toughness are enclosed with the crystal grains 1 that have low aspect ratios and small grain size and contribute to provide the material with superplasticity, in a three-dimensionally networked state is formed. Thus, the objective material provided with high superplasticity and high toughness concurrently, which properties can hardly be obtained by any material having a single structure, can be produced. |
