Watch Dr. Roland Strietzel of Germany’s Bego take us through a 3D metal sintering system. Video by Taras Berezowsky/MetalMiner
(Continued from Part One.)
So what does gold have in common with non-precious alloys being used more frequently by dentists (besides the fact that they’re both involved in molding crowns and the like)? Quite simply put, the higher price of one (gold) drives the demand for and use of the other (non-precious alloys) most notably, the so-called ËœCoCro’ alloys, or cobalt chromium.
I came to realize that this is indeed more than a passing trend while attending the 2011 Lab Day here in Chicago, a conference specifically designed for dental laboratory “decision-makers as LMT Communications, the organizing firm, puts it. A two-day affair that showcased various cutting-edge technologies, such as 3D printers (which was, honestly what I came to see), the conference mainly focused on plastics and ceramics from my perspective. (Side note: although EOS didn’t have a working 3D metal printer at the conference, Jessica Nehro, an EOS marketing associate, told me that “two of the fastest growing markets currently for [the company’s] laser-sintering solutions are medical (of which dental is a sub-market) and aerospace due to developments of such materials as EOS Ti64, Ti64 ELI, StainlessSteel PH1, PEEK HP3, Aluminum ALSi10Mg and NickelAlloy IN718 and IN625.”)
However, Dr. Roland Strietzel, a chemist and research developer at Bego in Germany, took dental lab technicians through the non-precious metal alloy sector, and how Bego and many other companies are constantly developing newer alloys to avoid the rising cost of gold. Strietzel said that something like 42 tons of precious metal alloy specifically for dental use had been produced in Germany in 1989, but last year, only 11 tons had been produced. Recently, Bego has taken the lead in alloy production by introducing SLM (selective laser melting) technology into dentistry in 2001 essentially metals-specific 3D printing.
“Milling is costly, and 90 percent of the material is thrown away, Strietzel said. “It makes no sense whatever economically.
Bad for cobalt producers but good for buyers, cobalt is set to face a large surplus this year, with predictions of a drastic price drop becoming more common in the analyst sphere. The LME cobalt spot price stood at $18.08 per pound on Mar. 1, as opposed to gold, which stands at a spot price of $1420.70 per ounce. A gram of CoCr alloy, for example, costs about 50 cents, Strietzel said.
As far as researchers are concerned, using CoCr and other such alloys (including NiCr) are not only cheaper but also more stable. For example, CoCr has higher mechanical values than precious metals, lower heat conductivity, more hardness, and higher stability, which makes it possible to work within a more delicate framework.
Now, as I mentioned in the previous post, here’s where we get into the international trade sphere: the world market gets much of its cobalt from the Democratic Republic of Congo (DRC) via China, and the recent conflict minerals rule which contributor Lawrence Heim has taken MetalMiner readers through in series of posts has spurred confusion among cobalt suppliers. The issue becomes compounded when considering Wikileaked cables in which Hillary Clinton “dubbed a cobalt mine in the DRC as critical to the security of the United States, prompting speculation over whether cobalt may be considered a conflict mineral in the future.
David Weight, the general manager of the Cobalt Development Institute, is quoted in the article as saying, “Industry wants to be sourcing from responsible, sustainable areas and [Dodd-Frank] has laudable aims, however, there is some confusion over different geographical regions of the DRC where this type of legislation is most likely to affect the cobalt industry. In his view, however, cobalt is not a conflict mineral.