Various types of structural materials are used in airplanes, and these materials are all subject to degradation. These mechanisms of degradation are based on phenomena that are quite different from those affecting steel and metal alloys. In Japan, a major national project known as “SM4I” (Structural Materials for Innovation) is underway, focusing on the structural materials used in airplanes. SM4I is one of the eleven R&D projects constituting the Cross-ministerial Strategic Innovation Promotion (SIP) Program, started in Oct. 2014 by the Council for Science, Technology and Innovation (CSTI) of the Cabinet Office. The goal of this project is to realize scientific and technological innovation strategically under its initiative. In SIP, industry-academia-government collaboration is emphasized to link fundamental scientific research and applied technology development.
In the SIP-SM4I project, the R&D target is the development of strong, light, and heat-resistant materials for application to the transportation industry, including aircraft, as well as the energy industry, accompanied by an improvement in energy conversion and usage efficiencies (Fig.1). Furthermore, the great contribution of materials technologies to the development of Japan’s aircraft and related industries is expected.
To attain the above objectives, the following R&D domains related to the development of aircraft engines and airframes have been designated.
Official site of the project (in Japanese) http://www.jst.go.jp/sip/k03/sm4i/
In the SIP-SM4I, a “IMASM (D66) unit” is intended to become the hub of the characterization of materials by using unique and advanced observation techniques. The “D66 unit” is made up of five national institutes: The National Institute of Advanced Industrial Science and Technology (AIST), the National Institute for Materials Science (NIMS), the University of Tsukuba, High Energy Accelerator Research Organization (KEK), and the University of Tokyo. As a member of the D66 unit, Team KEK is focusing on in situ microscopy and spectromicroscopy to obtain information on the heterogeneity in the chemical states as well as in the microstructures, and to reveal the initiation and propagation of fractures and degradation (Fig. 2).
Some of ongoing projects include: (a) the in situ observation of crack formation in multi-scales of FOV (from a few μm to a few tens of mm) in CFRP and ceramic coatings using X-CT, (b) chemical state mapping using X-ray absorption in multi-scale FOV (from a few μm to a few tens of mm) in oxide, ceramic coatings, and CFRP, (c) application of informatics and/or applied mathematics to the handling of multi-dimensional data such as chemical states and/or microstructures as a function of space (3D), energy, and time. New X-ray microscopy equipment (XAFS-CT) will be installed in the beam line of AR-NW2A, in PF-AR, KEK in FY2016; with this equipment, an X-ray beam will be focused onto a specimen through a capillary condenser, and a full-field transmission image will be obtained using a zone-plate. By scanning the X-ray energy, we will be able to obtain 3D X-CT images with X-ray absorption near-edge structure (XANES) spectroscopy (Fig. 3).