9th most read article of 2025: Aerospace industry increasingly turns to PVD coatings to replace hard chrome

The search for a suitable replacement to hard chrome on aerospace components has been a key supply chain priority for aircraft manufacturers. This is because of the documented health risks to workers and the impact on the environment from exposure to hexavalent chromium, a carcinogen that occurs during the chrome plating process and the most toxic form of chromium.

As a result, chromium is a highly regulated chemical in major markets worldwide. In the European Union, hexavalent chromium falls under the domain of the European Union Registration, Evaluation, Authorization and Restriction of Chemicals (REACH) regulation, which establishes guidelines for the safe use of chemicals throughout the supply chain. Chromium is also closely regulated in the United States by the Occupational Safety and Health Administration (OSHA).

However, replacing hard chrome with a suitable alternative remains a significant challenge for the aerospace industry because of its widespread use as a surface coating on many components. Long prized for its hardness, ability to minimize sliding wear, corrosion protection, and for extending the life of metal parts, hard chrome can be found on many applications such as aero structures, landing gears, engine mounts, and air frames. In many cases, it is used on components where there is metal-to-metal contact between moving parts due to its low coefficient of friction.

As a result, the process of replacing hard chrome requires aerospace companies to critically evaluate why they used hard chrome in the first place and to identify what problems it was addressing as they now seek to replace it with an alternative. This is a huge undertaking as each part that currently uses hard chrome needs to be reviewed for its functionality, its connectivity to other parts, wear mechanisms, lubrication needs, and environmental operating conditions. This analysis is necessary as there is no exact replacement for hard chrome.

Read more about how physical vapor deposition (PVD) coatings, a strong, non-hazardous, REACH-conforming replacement, are an option to hard chrome.