Soviet titanium creep-fatigue discovery (1982)

The Soviets built the Alpha subs using heavy-section titanium that the US could not match. Gurevich at Paton Welding Institute did the research from the 1960s, stopped publishing in 1972 when the program went black. Tom estimates $100M of research funding. Soviets didn't crack creep-fatigue interaction either, NRL eventually did.

One of the problems in the titanium business is that it's not a big enough industry to sustain its own rolling and melting facilities. They borrow time, rent time on a steel mill — they go in one day in a steel mill to roll the titanium they need for a month. They can't afford a half-a-billion-dollar rolling mill. They have to go roll in a dirty little steel mill, which creates its own problems. We never had a big titanium industry. The Soviets did. And the Soviets built the Alpha subs.

US Naval Research Lab had characterized titanium creep-fatigue at room temperature: under high compressive stress, fatigue cracks initiate readily. In 1982 the US learned the Soviets had not solved the problem either — they had built the Alpha subs without a solution.

That was good, but the even better thing is, I remember going to a meeting and they said, how do the Soviets solve the creep-fatigue interaction? It turns out titanium will creep and fatigue at room temperature or below. And what's the temperature of the ocean? It's sort of room temperature or below. At the time, the Navy had a big group doing development of titanium and I was being funded by the Office of Naval Research, so we were talking. And they said, how'd they solve the fatigue interaction? The U.S. Naval Research Lab had studied the creep and fatigue behavior at room temperature of titanium: if you have it under a big compressive stress, it would fatigue very readily. That's what they call the creep-fatigue interaction. I said, I don't know.

NRL had studied creep-fatigue interaction in titanium and identified it as a barrier to U.S. titanium submarine construction. The Soviets didn't know about it and built the Alpha class anyway, learning the hard way. Tom received NRL questioning at David Taylor / Carderock conferences in the early 1980s.

It turns out that if you compress titanium and hold it under compression, fatigue cracks grow really fast. Well, guess what a submarine hull is — it's held under compression when you're down deep. So there were several problems with the titanium subs of the Soviets. Certain things weren't a problem: they could go faster underwater than our destroyers could go on top of the water. They could dive deeper than the collapse depth of the depth charges. Some of these things concerned people, although one person who did a lot of work for the Rocky-class said, well, if you use the right type of depth charge you only have to get within a few miles. I thought, yeah, and as soon as you start doing that we have bigger problems. But in any case, we could have gotten rid of them.

Why the US chose not to build titanium submarines despite Soviet leapfrog. Hull cracking from creep-fatigue interaction. Faster than US destroyers; deeper than US depth charge collapse depth.

I said steel is heavy. To give you an idea: [Tom holds up a steel sample.] this is a piece of one-inch steel made about thirty years ago. [Tom holds up a second sample.] This is a piece of two-inch-thick titanium electroslag weld made at our Graduate Center when we were looking at trying to build a titanium submarine. Why have we not built a titanium submarine? A long time ago the Soviets did that. The main source of titanium — it's like aluminum, it's about the fifth most abundant element in the Earth's crust. Titanium is not scarce.

Tom traces the full arc: the 1980 *International Herald Tribune* announcement that caught the U.S. Navy flat-footed; the thirty-year prior U.S. Navy titanium program at David Taylor (welding 1–4 inch titanium since the 1950s); the Naval Research Lab's identification of creep-fatigue interaction as the Achilles heel; Tom's 1980 visit to the Paton Institute under the Carter-era U.S.–Soviet electrometallurgy exchange, where he spent two hours with Gurevich (Mr. Titanium, who had stopped publishing in 1972 when Alpha design began); the discovery that the Soviets never solved creep-fatigue and the subs cracked and became acoustically detectable within three years; and the Reagan administration's slamming of the exchange door. The case carries the lecture's deepest teaching: that the U.S. Navy's caution was vindicated, one titanium sub costs ten steel subs, and Congress later zeroed Millard Firebaugh's SSN-21 budget in pursuit of composite submarines.

When the Alpha sub first came on the scene, 1980 — what's the Alpha sub, everybody know? You haven't seen The Hunt for Red October? Tom Clancy. The Alpha sub was the all-titanium attack submarine that the Soviets dropped on the world in 1980, and it was a real eye-opener for the U.S. Navy. The Navy had been looking at titanium for submarine hulls for thirty years — since the early 1950s. The full story probably goes back to World War II. Because of the Manhattan Project, MIT mechanical engineering developed very effective vacuum systems for what they called vacuum metallurgy. You could now melt reactive metals under a full vacuum, whereas they really didn't have the technology to do this on an industrial scale before that.