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November 24, 1999

3 Min Read
Materials for IMMC:  Stainless steel goes nickle-free

Allergic reaction to metal alloys that contain nickel, like stainless steel, has become a serious and growing problem in industrialized areas of the world. Some European countries have already enacted legislation to regulate exposure to nickel from items that come in direct and prolonged contact with the human body, such as dental braces, jewelry, watch parts, and medical implants.

Last year, BASF introduced an austenitic stainless steel/polyacetal-based feedstock for MIM called Catamold Panacea (Protection Against Nickel Allergy, Corrosion, Erosion, and Abrasion).

True to its name, this feedstock contains a powder that is a lot more than merely nickel-free. In fact, its inventors believe its superior mechanical properties will allow it to replace commonly used austenitic stainless steels like 316L in several applications where nickel allergy is not a concern.

It was invented at the Swiss Federal Institute of Technology (Eidgenössische Technische Hochschule, or ETH). Markus O. Speidel is the director of ETH’s Institute of Metallurgy. When we visited him and his associate, Peter J. Uggowitzer, at their offices in Zurich, we asked them if BASF contracted ETH to develop the material.

“No,” Speidel replies. “It was the other way around. We had the idea of solving the nickel allergy problem through metallurgical means more than five years ago. Our original goal was to develop the very best material possible for use in, at, or around the human body. But we knew little about MIM at that time.”

A Cure-all for MIM?
He said he learned of MIM at a technical conference. He contacted one of his former students—Georg N. Breitenmoser, founder of MIM molder Parmaco AG in Fischingen, Switzerland. After Breitenmoser schooled his former teacher on MIM, Speidel and Uggowitzer took their product to a major Swiss watch manufacturing company that had begun MIM molding of watch parts. Subsequently, this company introduced ETH to its feedstock supplier, BASF.

“BASF quickly realized its potential, but it feared the high development costs and wanted exclusivity,” Speidel recalls. “ETH does basic research, often with public funds. If we develop something that is marketable we share a percentage with the Swiss government and with ETH. We granted exclusivity to BASF and signed the contract.”

Osprey Metals Ltd. (Neath, U.K.) was contracted to produce the powders. The ETH technology starts with a high-manganese ferritic powder. It is transformed into austenite through solid-state nitriding during and after sintering.

Speidel is excited about the use of the material in nickel-free applications and is equally excited about possible applications exploiting the material’s superior corrosion, scratch, and wear resistance (Figure 1); high hardness and toughness; and absence of ferromagnetism. He hints at a very big wear-resistant automotive application coming soon, but declined to offer details.

“My vision is that our nickel-free material eventually will replace at least 10 percent of all stainless steels,” Speidel concluded.

Contact information
ETH
Zurich, Switzerland
Markus Speidel
Phone: +41 (1) 632 25 91
Fax: +41 (1) 632 11 01
E-mail: [email protected]
Web: www.met.mat.ethz.ch

BASF Aktiengesellschaft
Ludwigshafen, Germany
Hans Wohlfromm
Phone: +49 (621) 60-55754
Fax: +49 (621) 60-22198
E-mail: [email protected]
Web: www.basf.com

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