19 What Does the Future Hold? Very few people,if any,probably would have predicted 50 years ago what kind of materials would dominate our technology to- day.Who could foresee the computer revolution and thus the preponderance of silicon in the electronics industry?How many scientists or engineers prognosticated the laser and its impact on communication,data-processing,data storage,and thus on op- tical materials?Was there anybody who foretold,50 years ago, the impact of superalloys,of composites,or of graphite fibers as important materials?Were ceramics not essentially perceived as clay and sand;that is,could anybody anticipate high-tech ce- ramics,including high Te-superconductors,heat-resistant tiles (for space shuttles),silicon carbide engine parts,etc.?And finally, how many people could visualize 50 years ago the impact of plas- tics as one of the prime materials of the present day,or an ac- centuation on recycling and environmental protection? On the other hand,nearly "everybody"predicted only 15 years ago that composites and ceramics for high-temperature engines would be the materials which would enjoy healthy growth rates in the years to come.This,however,has not happened.One of the major funding agencies in the United States (ARPA)has recently stated that the past 20 years have not brought the expected progress in structural ceramics,brittle matrix composites,or intermetallics. It is said that these"exotic"materials may probably never be used in critical parts such as turbine blades because they are too brit- tle,and a balance of properties may probably never be achieved.A 50%cut in support for the ensuing projects has therefore occurred. Instead,a resurgence of substantial interest in metals research may boost,for example,nickel-based superalloys (e.g.,Ni-Al)which are often coated with um-thick heat barriers.These coatings,consist-19 Very few people, if any, probably would have predicted 50 years ago what kind of materials would dominate our technology to￾day. Who could foresee the computer revolution and thus the preponderance of silicon in the electronics industry? How many scientists or engineers prognosticated the laser and its impact on communication, data-processing, data storage, and thus on op￾tical materials? Was there anybody who foretold, 50 years ago, the impact of superalloys, of composites, or of graphite fibers as important materials? Were ceramics not essentially perceived as clay and sand; that is, could anybody anticipate high-tech ce￾ramics, including high Tc-superconductors, heat-resistant tiles (for space shuttles), silicon carbide engine parts, etc.? And finally, how many people could visualize 50 years ago the impact of plas￾tics as one of the prime materials of the present day, or an ac￾centuation on recycling and environmental protection? On the other hand, nearly “everybody” predicted only 15 years ago that composites and ceramics for high-temperature engines would be the materials which would enjoy healthy growth rates in the years to come. This, however, has not happened. One of the major funding agencies in the United States (ARPA) has recently stated that the past 20 years have not brought the expected progress in structural ceramics, brittle matrix composites, or intermetallics. It is said that these “exotic” materials may probably never be used in critical parts such as turbine blades because they are too brit￾tle, and a balance of properties may probably never be achieved. A 50% cut in support for the ensuing projects has therefore occurred. Instead, a resurgence of substantial interest in metals research may boost, for example, nickel-based superalloys (e.g., Ni–Al) which are often coated with m-thick heat barriers. These coatings, consist￾What Does the Future Hold?