Making Pure Titanium at Rensselaer

Research in materials science has been an Institute strength since its earliest days. Monumental advancements in this area by Rensselaer faculty include producing pure titanium for the first time.

In the early 1900s, Matthew Hunter, a New Zealand native, had been working with titanium at General Electric before he took his research to Rensselaer when he was hired as a faculty member in 1908.

Titanium ore was first discovered in 1791 by William Gregor, a clergyman and amateur geologist in Cornwall, England. A few years later, a German chemist, M.H. Klaproth, named the metal after the Titans, the giants of Greek mythology.

In 1910, Hunter was the first to produce pure metallic titanium by heating titanium chloride together with metallic sodium. Because of the violent process, the experiment was done in an airtight steel cylinder. Many of these experiments took place on the ’86 Field. Hunter believed titanium had a high melting point and therefore was a candidate to replace the carbon filaments then used in light bulbs.

Although he was the first to isolate usable amounts of the metal, the melting point turned out to be lower than Hunter expected, making titanium useless for light bulbs. Nevertheless, he showed that the metal had some ductility, and his method of producing it was later commercialized and is known today as the Hunter Process.

In 1933, Rensselaer’s Board of Trustees established the Department of Metallurgical Engineering, which Hunter organized. He became head of the department in 1935 and was named dean of faculty in 1943. The Matthew Albert Hunter Prize in Metallurgical Engineering was established in 1951. The prize is awarded annually to a senior in materials science and engineering who has demonstrated outstanding ability in academic work leading to a career in that field. The Department of Metallurgical Engineering was eventually transformed to what is known today as the Department of Materials Science and Engineering.

Although it is the ninth most abundant element in the Earth’s crust, titanium is expensive but not because it is rare. Titanium is not found in nature in its purest form; it must be extracted from other compounds, requiring a significant amount of energy and labor.