Chromalloy HIP rejuvenation with Greek Navy student

Tom's student work with Chromalloy: hot isostatic press treatment at 20,000 psi argon used to restore the fine gamma-prime structure of coarsened turbine blades without melting them, preserving the buyer's license to use the patented alloy.

It turns out it was a Greek Navy student who worked with me, with a company called Chromalloy, and we basically — couldn't melt it, but we took these old turbine blades and we gave them a hot isostatic press heat treatment. I've talked about this hot isostatic press, where you go up to 20,000 psi in an argon atmosphere and heat it up, and you re-heat-treat it. By doing hot isostatic press heat treatment on these parts, we could bring it back to its original structure without melting it and re-solidifying it. We could get back the very fine phase, getting it very close to the melting temperature but not melting it, because it came back out of the HIP unit with the same shape that it went in at — so we obviously didn't melt it. And so they could reuse the ones they had bought, okay. It doesn't happen very often, but someone gets a patent late and it surprises everybody and they're not happy.

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