Turn Back the Time: Steel for Watches

For smartwatches and watches, different materials can be used. Among the most used materials are aluminium, titanium and steel – and stainless steel in particular.

Stainless steels like Acidur 4427 that are used in precision engineering/ watches must combine a wide range of properties. In addition to good machinability and high surface wear resistance, a very high degree of cleanliness is required for the production and use of components that are only a few millimetres in size. Acidur 4435 in its remelted variants Acidur 4435 Superclean (ESR) and Acidur 4435 Ultraclean (VAR) fulfils even the highest quality requirements without any problems. The non-magnetic grade Acidur 4435 is characterized by high corrosion resistance and good suitability for high-gloss polished surfaces.

Learn more about ESR and VAR remelting processes.

In addition to stainless steels, there are also some other suitable materials on the market.

Ferro-Titanit U

Ferro-Titanit is a high-alloyed, machinable and hardenable metal matrix composite based on steel. The material combines the properties of steel and cemented carbide. Ferro-Titanit has a titanium carbide content of roughly 45% by volume, embedded in an alloyed steel binder phase. In addition to very high wear resistance and high corrosion resistance, the non-magnetic grade Ferro-Titanit U is characterized by a low thermal conductivity and low specific density. This means it is 50% lighter than cemented carbide and still 15% lighter than steel. This combination of properties offers advantages when designing certain products, e.g. watch housing. Side effect: the low thermal conductivity in combination with the reduced density lead to a sense of well-being. The material appears warmer (low thermal conductivity) and lighter (reduced density) – everything that you expect from a comfortable watch.

Explore different grades of Ferro-Titanit here.

Materials of tomorrow

Whether in aerospace, medical technology, toolmaking or the automotive industry - additive manufacturing (AM) is on the advance. In contrast to mechanical manufacturing processes such as milling, turning, etc., in additive manufacturing the component is built up layer by layer. This approach allows a high degree of freedom in the design of, for example, watch cases or bezels. AM grades that are relevant in this field of application are Printdur Ni625, Printdur CoCrF75 and the new metal powder grade Printdur HSA.

Printdur Ni625 is a NiCr-superalloy that is typically used in high-temperature applications. Its good mechanical properties, as well as its very high corrosion resistance, makes it also suitable as a watch material. The other example is Printdur CoCrF75. Like Printdur Ni625 it can be used in high-temperature applications, but in addition also in medical applications. Printdur CoCrF75 is a CoCrMo implant alloy with very high biocompatibility and corrosion resistance. It also impresses with a combination of high strength with good ductility and high fatigue strength.

Printdur HSA is a high strength austenitic grade. Compared to typically used stainless AM steels like 1.4404 (316L), Printdur HSA is characterized by a higher hardness. This makes cases made of Printdur HSA much more resistant to scratches. Due to it not containing nickel or cobalt, Printdur HSA will not be in conflict with (possible) upcoming REACH regulations and is therefore well suited for the future.