Solid As Steel, Light as a Cushion

By THOMAS McCARROLL

Even from a distance, the grayish two-story home with panoramic windows and pointed chimney casts a distinctive profile against the suburban sky. But only a closer inspection reveals what is truly unique about this house. Instead of sporting bricks or aluminum siding, the dwelling is covered with superstrong, superdurable plastic panels. The shingles on its vaulted roof are made not of wood but of another tough plastic; so too, in fact, are the floors, doorframes, light fixtures, plumbing pipes and even the windows.

This experimental "plastic" house, built by General Electric in Pittsfield, Mass., is perhaps the most striking use so far of a new class of souped-up substances called advanced materials. These novel building blocks are basically futuristic versions of present-day metals, glasses, plastics and ceramics. But unlike conventional counterparts, the materials are made with extra ingredients that greatly enhance their performance or give them new features. By blending in stiff carbon fibers, for example, modern-day alchemists have developed plastics that are up to 10 times as strong as conventional plastics. And by mixing copper with zinc and aluminum, scientists have produced a metal with a "memory": the stuff returns to its original shape after being bent or twisted.

The new materials are usually designed on computers, which can analyze exactly how the molecules of different substances will fit together. As a result, complex compounds can be made to order for specific tasks. They can be engineered to be as solid as cement yet as light as foam cushion, or sturdy like steel but pliable like rubber. Because of their superior properties, advanced materials are rapidly replacing ordinary steel, aluminum and plastics in everything from cutlery to cars. Scientists have high hopes of conserving natural commodities such as iron, wood and rubber. Says Robert Newnham, a professor of solid-state science at Pennsylvania State: "At one time, we had to settle for whatever Mother Nature gave us. Now if we're not satisfied we can go out and create our own materials."

Advanced materials are just now starting to show up in commercial products. Examples: ceramic scissors that never rust or get dull, plastic lumber that is water-resistant and does not swell or warp like wood, and "metal" windows that keep excessive light and heat out of a house in summer and trap them inside during winter. In the U.S. the aerospace industry, including the military, is the biggest consumer of engineered materials, accounting for more than two-thirds of all use. The substances, used in door panels and floors, account for about 14% of a typical airplane's weight, in contrast to 2% ten years ago. Stealth bombers and fighter jets are wrapped in skins of composite nonmetallic materials that help make the planes more difficult to detect with radar.

The fastest-growing market is the auto industry, which is increasingly replacing metal with lightweight plastics in bumpers, body panels and other parts. These polymers typically weigh half as much as steel but are just as strong. The plastics conserve gas by making a vehicle lighter, and manufacturing them requires 10% to 20% less energy than fabricating metal parts. Admittedly, there can be problems. General Motors found that the polymer body panels of some of its minivans started to peel like old wallpaper. Moisture had seeped between the sheets of plastic and caused the panels to come unglued.

But such minor glitches have done nothing to dull the enthusiasm for developing even more exotic materials. By combining particles of chlorophyll with molecules of a soft plastic, researchers at M.I.T. have made a rubbery gel that shrinks and swells in response to an electric charge. The substance could conceivably be used to make artificial muscles. A superhard ceramic is being developed to make engines that do not need oil or a radiator, and get 100 miles to a gallon of gas. Scientists are also working on a "smart" ceramic that can respond to stress. Simply put, the material is laced with tiny electronic components that react to pressure or other stimulation by emitting some signal -- rays of light, for example. Designers envision using this ceramic to build a bridge that would change color if it were overloaded and thus became structurally unsound.

Such potential has made the materials business one of the most hotly contested high-tech fields. Hundreds of companies, from IBM to Germany's Daimler-Benz to Japan's Sony, are investing heavily to come up with the next breakthroughs. Advanced-material sales, which will top $2 billion this year, are expected to reach $20 billion by the year 2000 as research efforts of the past decade start paying big dividends in the form of new products.

Until a few years ago, U.S. companies were the undisputed leaders of the industry. But analysts warn that America may be losing ground -- once again to the Japanese. Unlike firms in the U.S., where the use of new materials is confined mainly to aerospace and the military, Japanese manufacturers are concentrating almost exclusively on industrial and consumer applications. In addition, they have been avidly buying materials technology from abroad. In the past four years, some of Japan's leading producers, such as Kyocera and Tokuyama, have acquired four American firms, including AVX, a New York City manufacturer of specialized ceramics, and Materials Research, an Orangeburg, N.Y., company that makes high-purity metals.

But in the race to build advanced materials, technological prowess and financial clout may not count as much as imagination. The winners will be those who can not only fabricate exotic materials but also dream up myriad ways to use them.