Balzers PVD tool coating –investigation of the environmental aspects

As a division of Unaxis, Balzers AG shares in the corporate commitment to sustainable busi-ness activity. Balzers products have long helped customers to achieve ambitious targets. Take diesel engines, which are reaching new lows in emission figures thanks to components coated by Balzers AG. Or tools: Balzers PVD coatings minimize friction and improve surface char-acteristics, which in turn saves coolant oil and lubricants. Yet for all these successes, little has been known to date about potentially negative environmental impacts of PVD coating. Balzers therefore decided to perform a thoroughgoing environmental evaluation of its proc-esses and products, to produce new findings and alleviate doubts among customers and em-ployees. When analysis began back in 2003, major factors for the environment were identified as preparing items for coating, and consumption of target material and energy during the coat-ing process itself. But these results did not reveal much about the overall environmental im-pact of PVD processes: it was still unclear whether customer gains from PVD coating also added up to greater environmental harm, all things considered. To address these doubts and produce new findings based on practice, the study was extended to tool coating activities. Three industrial scenarios were selected as a basis for investigating:

- whether Balzers PVD tool coating can reduce the total burden on the environment;

- which process steps in the tool lifecycle had the greatest environmental impact.

The investigation focused on typical tools, the kind that are routinely coated and used in pro-duction around the world. Appraisal and analysis followed established and recognized ISO 14040ff methodology for drawing up an ecological balance sheet. The Karlsruhe research center of the Helmholtz Gesellschaft was brought on board as an independent partner to verify the analysis as well as the conclusions.

The tools examined by the study were selected on two criteria:

1. Existence of a fund of current industrial experience

2. Tools had to be made from commonplace basic materials

Two drills and a forming die were thus selected for a lifecycle analysis. The drills were made from high-speed steel and carbide; the forming die from hot forming steel.

The investigation revealed that negative environmental effects attributable to Balzers PVD coating were only a minor element in the tool lifecycle. Far more drastic were the resources consumed in producing the basic metallic tool materials, along with subsequent hardening and sintering processes. Given that Balzers PVD coating improves tool performance, prolongs service life and economizes on further consumption of resources for producing new tools, the bottom line is that the Balzers PVD coating process contributes to markedly reduced overall environmental impact.

Unaxis Balzers AG coats all kinds of tools – over 60 million pieces each year. Most are made of carbide, others from steel. Balzers PVD coating multiplies the tools’ performance many times over, but even a simple doubling translates to global savings on the order of:

- > 200 million MWh of primary energy

- > 60 million kg of CO2

- > 30,000 kg of NO2

These results demonstrate that customers of Unaxis Balzers AG not only derive economic benefits from PVD coating, but also do good for the environment.