GTD-111 superalloy patent dispute

Another externality, and this one has to do with intellectual property. It has to do with large turbine blades. These are land-based turbines. I'll pass around — this one comes from either a 757 or 747 engine from about twenty, twenty-five years ago, maybe even older. You can take it apart. It's a single crystal turbine blade. It's been cut by wire electrical discharge machining so you can see the inside structure, and they cool these things with the compressor air from the engine. The cooling air is about 500° Fahrenheit because that's the temperature when you squeeze the air in the engine to thirty atmospheres pressure so you can burn it.

Another type of externality is intellectual property. General Electric patented a nickel-base superalloy called GTD-111 in the mid-1970s, and it became part of a lot of their land-based turbines, and in some cases aircraft turbine engines. Starting in the 1980s and 90s, as the patent was expiring, other people realized this was a good alloy with good high-temperature properties, and they started designing it into their engines.

GE developed GTD-111 in early 1980s but couldn't patent the composition (too overlapped); patent office denied the heat-treatment patent for 18 years, then granted it after competitors had adopted the alloy. Royalty windfall. Chromalloy rejuvenation work on GTD-111 blades via HIP ties the case to §4.

There's a story here. There was a General Electric alloy called GTD-111, and it had this very blocky, squarish gamma prime precipitate. The composition was overlapped by lots of other alloys, so when General Electric developed it in the early 1980s they couldn't get a patent on the composition. They did apply for a patent on the heat treatment, and the Patent Office kept denying it.

The central developed case of the lecture. GE files a heat-treatment patent in ~1986; the patent office rejects; the industry adopts the alloy; ~2001-2006 the patent issues; everyone is suddenly infringing. Tom's master's-thesis student finds a HIP-based rejuvenation workaround for an engine-refurbishment company.

This is actually a structural material — the firing temperature of engines. I've got my turbine blade going around there somewhere. This is firing temperature versus time — the higher the temperature, the more efficient the engine. These are the materials capabilities. Here's an interesting one, GTD-111. [Tom shows a broken fan blade.] Here's a broken GTD-111 fan blade. This is directionally solidified GTD-111. General Electric came up with this alloy in the 1980s — it was an improved alloy. Then we got single-crystal blades like I'm passing around. The firing temperature of the engine goes up. But finally they couldn't get any better until they went to air cooling — those air passages through that blade — and you had a tremendous jump.

GE applies for heat-treatment patent on a public-domain alloy in the early 1980s; patent office grants it nearly twenty years later, in 1997-98, after competitors have already designed the alloy into their systems. Used to introduce HIP rejuvenation as a way for buyers to legally re-condition aged parts they had previously purchased.

I'll tell you a little story about these types of structures. General Electric makes jet engines, and not only that, big land-based turbines for generating electricity. They came up with a modified alloy back in the early 1980s, that they called GT-100. GT-100 was not such a big change in composition from other alloys, and so they decided they couldn't patent it. Well, it turns out it was a pretty good alloy, and other people building turbines — like their competitors Siemens or Pratt Whitney [Pratt & Whitney] — decided well, this is a public-domain alloy and we can design it into our systems, and they did.