aterials Science and Engineering Laboratory

Materials are so basic to human progress that their importance is hard to overemphasize. Every technological advance, from the first stone hammer to today's most complex integrated circuits, sprang from the mastery of specific materials. Accomplishing many of the nation's goals, such as the National Aerospace Plane, faster computers, or electrical energy from nuclear fusion, hinges on our ability to develop new materials that are far superior to those used today. Indeed, the technological and economic goals of many other countries are also tied to advances in materials, setting the stage for intense international competition. For example, more than half of Japan's 13 priority research and development projects involve materials science. In Europe, the Commission of European Communities has set up national and international cooperative programs that focus on advanced materials.

Research on advanced ceramics, metal alloys, polymers, composites, and the new hightemperature superconductors has already exposed some of the future technological possibilities. The ability to microengineer these materials to create submicroscopic structures and combinations of elements unknown in nature has resulted in properties and phenomena that until only recently were beyond the imagination. Now that our imaginations have been piqued and our appetites for innovation whetted, our challenge is to transform these materials from laboratory curiosities to viable products and manufacturing processes.

At the National Institute of Standards and Technology (formerly the National Bureau of Standards), the Materials Science and Engineering Laboratory (MSEL) is responding to this challenge in many ways, addressing scientific and measurement issues that are crucial to industry's success in exploiting the potential technological advantages of advanced materials. Consistent with the Institute's mission as the national measurement and engineering laboratory, the activities of MSEL's six units emphasize research leading to the development of standards, test methods, and reference data and materials. The guiding tenet for this work is a simple maxim: If a process or property cannot be measured, then it is not completely understood. Inherent in MSEL's mission is the need to develop scientific understanding of the underlying physical and chemical origins of the properties being evaluated.

Covering all classes of advanced materials, as well as major conventional materials, the Laboratory's research program investigates the relationship between the structure and properties of materials and then applies the resulting knowledge to issues related to the design, processing, and performance of materials. Our approach encompasses the full range of research and development activities, from basic studies to generic applications. The examples of MSEL research accomplishments described in this publication illustrate this R&D strategy.

Toward Automated Process Control

n recent years, the focus of the Laboratory's attention has increasingly turned toward improving the understanding of materials processing. Our ultimate goal is to help U.S. industry develop real-time, automated systems of process control, so-called intelligent manufacturing methods that improve product quality and increase production

efficiency. As study after study has pointed out, firms that emphasize product quality throughout the manufacturing process, rather than at the end of the line only, will strengthen their competitive position.

Intelligent processing of materials is itself the result of a process, the evolutionary development and application of scientific and engineering knowledge. Projects under way in the five MSEL divisions and those managed by the Office of Nondestructive Evaluation are gathering and evaluating muchneeded data on structures and properties of materials, at increasingly fine levels of detail and under the increasingly extreme environmental conditions that characterize many high-performance applications. These data support the development of process models, which relate the specific properties of materials at each manufacturing step to the properties of the final product.

In tandem with data-gathering and modeling efforts, MSEL researchers are building and refining real-time sensors for in-process nondestructive measurements. They then develop strategies for coupling on-line measurements with process models. This work establishes the foundation for the final step-merging sensors and models with automation technology to create a truly integrated manufacturing system. Without closed-loop process control, manufacturing methods will be inefficient, often failing to achieve the carefully controlled microstructures that govern the performance and reliability of advanced materials.

As you will see, process control is the common thread that unifies the Laboratory's varied technical activities-from the development and refinement of theory to innovative methods for on-line nondestructive evaluation. Our work exemplifies the increasingly. close link between basic scientific understanding and technological innovation.