Niobium-titanium superconductor development for high-energy physics

John Wulff's work; critical temperature ~9 K, fields ~6 Tesla. The 1970s workhorse superconductor.

The superconductors that were being used for the high-energy physics experiments in the 1970s were typically niobium-titanium. The guy who really worked here a lot on that — he didn't discover it — was John Wulff. He was teaching 3.091. He taught 3.091 in '76 when he turned 65 and he couldn't teach anymore under the old rules. You had to retire at age 65 before about 1982. Somewhere around 1980, Congress — with an average age of 77 — passed a law that you could not force a faculty member to retire at age 65. But before that, all MIT faculty had to retire at 65. John Wulff retired at 65, and they had this thing that you could keep teaching for five years until you were 70, but you could only earn half pay. So John Wulff, in order to earn half pay, started teaching 3.091.

GE niobium-tin and other manufacturers' niobium-titanium magnets, ~1960, for physics. Establishes the pre-1986 commercial baseline against which high-Tc was hyped.

Here's a brief history of superconductive materials: "Although the phenomenon of superconductivity was discovered over 60 years ago" — well, in 1975 — "it has only been in the past decade that its technological potential has begun to be utilized." That's because General Electric started selling niobium-tin (Nb₃Sn) superconducting magnets, and other people had made niobium-titanium superconducting magnets around 1960, mostly for high-energy physics experiments where they needed high magnetic fields. "Early in its history, superconductivity was envisioned as a means of lossless electrical power transmission" — solving the problems under New York City — "and of generation of large magnetic fields," such as high-field magnets for physics experiments. "In fact, in terms of energy input, a superconducting magnet would consume a few kilowatts of refrigeration compared to the megawatts of resistive heat loss."