Development of Manufacturing Process of Multilayred Composite with Mesoscopic Microstucture

在介观尺度上控制材料的微观结构以优化材料的性能是创造性地开发高性能新材料的重要途径。作为这些想法之一，我们计划开发改进的Jerry Roll技术，其特征如下：（1）易于设计具有介观微观结构的复合材料，（2）通过重复塑性变形，可以获得具有非常高的变形率的最终细丝。取得了以下结果。(a)首先，通过理论计算，在一定磁场下获得最大临界电流密度，设计了Nb-Ti/Nb多层复合结构。理想的复合超导体是由杰里辊技术。他们的表现令人满意。(b)制备了厚度为10 nm的Ag/Cu多层膜，其抗拉强度超过1300 MPa，与理论Koehler固体近似。(c)通过控制易变质沉淀相的结构，研制出强度超过900 MPa的超高强铝合金。

To optimize the property by controlling microstructure in mesoscopic scale is the most important methodology to develope creatively a new matrial with high performance. As one of those ideas, we have planned to develope the modified Jerry Roll technique, of which characteristic features are as follows ; (1) it is easy to design the composite with mesoscopic microstructure, (2) by repeating the plastic deformation, it is possible to get the final fine wire with very high deformation ratio. The following results have been obtained. (a) Firstly the multilayred Nb-Ti/Nb composite structure was designed owing to the theoretical calculation getting a maximum critical current density at a fixed magnetic feild. The ideal composite superconductors were fabricated by the Jerry Roll technique. Their performance was found to be satisfactory. (b) The multilayred Ag/Cu film with thickness of 10nm was fabricated, of which the tensile strength exceeds 1300 MPa, of which value is in the same order estimated from the theoretical Koehler solid. (c) The super-high strength aluminium alloys have been developed by controlling the structure of metadtable precipiates and realized the strength beyond 900 MPa.