Cryogenics: It's not about freezing bodies

"We don't freeze bodies."

Brian Tomlinson has to tell people that about twice a week.

He runs Circle City Cryogenics, a division of Circle City Heat Treating Inc., and most everyone's first thought is that he freezes bodies in a sci-fi attempt to bring them back to life in the future.

Actually, cryogenics broadly refers to the branch of physics dealing with the effects of very low temperatures. The practice of freezing bodies to be awakened in the future is cryonics.

Tomlinson mostly freezes metal. When good quality metal is deep-frozen at minus 300 degrees, then warmed back up, it improves the wear resistance and strength of the material, lengthening the lifespan of the product. He also has seen improvements after freezing plastic, but most of his business is with metal.  Just about anything with metal can be cryogenically treated, he said — guitar strings, razors and gun barrels, as well as large machinery parts.

Circle City Cryogenics is a small part of what Circle City Heat Treating does, accounting for a little less than 5 percent of its business, said company President Tom Dunn. But not many people know about it, he said, and even fewer understand it.

Treating metal is a small part of the growing cryogenics industry. Many of the companies that make up the $14.5 billion a year industry sell medical and pharmaceutical equipment, such as the machines used to freeze off warts.

Ohio-based Worthington Industries recently bought the cryogenics assets of an Alabama-based company for $33.25 million. The assets include a plant that manufactures freezers, refrigerators and storage tanks that use cryogenic processes to aid in medical research. The industry is expected to grow to $21.09 billion by 2019.

As his company is the only one in Indiana that cryogenically treats metal, Tomlinson does his best to teach people about the effects of the process, which has been in use for more than a decade. He'll freeze anything once, just to try it. If he hasn't frozen the metallic product before, he'll try it for free as long as the customer shares the results with him.

Otherwise, he charges $6 a pound with a $95 minimum. The whole process takes about 72 hours. The freezing is accomplished with liquid nitrogen.

It sounds a little, as Tomlinson has been told, like black magic.

But Dudley Taylor, battalion chief for the Indianapolis Fire Department, said it works. Taylor used to oversee the maintenance of the city's firetrucks, and in the early 2000s, he was looking for a way to cut costs. He previously worked in car racing, and some racers cryogenically treat parts of their cars to gain advantage on the track.

"It was just looking for innovative ways of saving money, and it turned out it was a successful process for us," he said.

At the time, Tomlinson was part of the now-defunct Cryogenics of Indiana. Taylor took him some brake rotors off a truck and had them treated as an experiment. A firetruck that did 3,500 runs a year needed new brakes every six months because of the wear of stopping and starting while hauling all that weight. Taylor said he didn't tell the firefighters he'd changed anything, so they didn't use the truck differently.

Six months later, he took the truck in to check the brakes. No new parts were needed. It turned out the brakes lasted four times longer after the treatment. Each brake job for each of the department's more than 100 trucks costs $3,000 to $4,000, Taylor said. Cryogenically treating four rotors cost him about $200. He estimated that the cryogenic process saves the department more than $200,000 in brake jobs each year.

David Bahr, head of the Materials Engineering Department at Purdue University, cautioned that cryo-treating is not a one-size-fits-all solution. It can work very well on certain metal alloys, but it won't work with all metals.

Most metals are not composed of only one material, he explained. A steel bar might also contain manganese, tungsten, chromium or nickel. Depending on how the metal was processed originally, the metal will behave differently  based on the temperature, because the atoms of the alloys will line up in different patterns.

Think of it like a cup of tea, he said. When you put sugar in hot tea, it dissolves. If you freeze the tea, the sugar will precipitate and fall to the bottom. The amount of sugar in the tea is the same, but the temperature alters its behavior.

"Effectively what the cryo-treating is trying to do is to lock in or cause transitions (of alloys) to occur that only occur at low temperatures," Bahr said.

Those transitions can make the metal stronger and more wear-resistant, which amazed Ernie Gomez, acetylene plant manager for Indiana Oxygen Co., when he took some plant machinery parts to Tomlinson.

By treating steel parts, he extended their wear life by four to 16 times, depending on the part. Some of those parts once had to be replaced four times a year.

"It's going on three years now without replacing that part," he said. "I can't believe everyone doesn't do it."

Call Star reporter Ellen Garrison at (317) 444-6179. Follow her on Twitter: @EllenGarrison.