New Type of Superconducting Material Found : Research: Hitachi says its non-copper medium may be cheaper to produce than other methods under consideration.

Five researchers at a Hitachi Ltd. laboratory just outside Tokyo have discovered a new class of superconductor materials that could help bring the revolutionary technology closer to commercial production, the company announced Wednesday.

The new material, a ceramic that includes vanadium and strontium, would probably be cheaper to produce and use than copper-based materials being researched, said Shinpei Matsuda, head of Hitachi’s superconductor research effort.

Superconductors, which transmit energy without resistance, have the potential for opening the door to a new generation of products ranging from super-efficient generators to levitating trains.

But for most applications, the material must first be converted to wire at a reasonable cost. Laboratories around the world are spending hundreds of millions of dollars a year to overcome that obstacle.

It’s no simple task. Most new classes of superconductors are ceramics and too brittle to be turned directly into wire. Because the copper in the compounds reacts with lesser metals, the ceramic must be sheathed in silver to be given the malleability of wire.

Hitachi solved that problem by eliminating copper from the compound. The resulting material can be packed into hollow copper wire, offering the potential for vastly reducing the cost of the wire.

The new material also has the advantage of operating at a higher temperature. It becomes a superconductor after being cooled to minus 143 degrees Celsius. The best superconductors developed to date must be cooled to a temperature of minus 151 degrees Celsius before the electricity passes without resistance, Hitachi said.

Shoji Tanaka, director of a government-backed superconductivity research consortium, called Hitachi’s announcement “premature.”

“I would have liked to have seen them establish their data a little better before publishing their results,” Tanaka said.

Hitachi’s research results, which were submitted Tuesday to the Japanese Journal of Applied Physics for publication, are preliminary, Matsuda admitted.

“We have a runner on first. We need several hits before we can bring him home,” he said.

So far, the company has been able to manufacture the substance only in small quantities. Consequently, Matsuda said, the company has been unable to determine either the exact chemical composition of the material or the size of the current it can carry.

Inability to carry a sizable current would make the material impractical for most commercial applications. Even if the material proves too difficult to manufacture in large quantities, Matsuda said, the discovery would help scientists unravel the mysteries surrounding why certain materials act as superconductors by providing a whole new set of data.

Matsuda said the company’s new materials team tested thousands of materials for superconducting properties before discovering the new compound.

The team is part of a larger, 48-man group formed in 1987 soon after International Business Machines reignited interest in superconductors by announcing that it had discovered materials that become superconductors at far higher temperatures than previously thought possible.