With the European Chemicals Agency (ECHA) pushing forward its proposal to replace PFAS materials due to environmental and health concerns, industries have now the tasks of finding reliable alternatives. One key area impacted is the use of PFAS polymers as liners in the chemical industry, where high temperature and chemical resistance are essential. The selection of alternative materials for this application must meet these demanding performance requirements while complying with the new regulatory standards. During the project, some engineering plastics have been selected and evaluated as a possible replacement solution. 

Leaded solder alloys with low melting point are still permitted in the aerospace industry due to their high reliability for PCB assembly. However, the challenge arises when the final application requires the printed circuit board (PCB) to operate at extremely low temperatures. In this study, we selected a solder alloy that can operate in environments as cold as -170°C, with a melting point range between +120°C and +215°C. 

Hydrogen can significantly degrade the mechanical properties of many materials, including ferritic steels, nickel-based alloys, and HCP alloys. However, austenitic structures, especially austenitic stainless steels, are less vulnerable to hydrogen embrittlement due to their lower hydrogen diffusivity and higher solubility in FCC microstructures. For this reason, a modified version of stainless steel 316L was selected as the metal housing for a component that will come into direct contact with hydrogen gas. 

Hydrogen has one of the smallest molecules, making it extremely challenging to achieve a reliable seal. This project involved selecting an elastomer O-ring to be used in contact with hydrogen, within a temperature range of -40°C to +80°C. Materials like EPDM, NBR, HNBR, and FKM are considered viable options for hydrogen applications.

However, the additional challenge was ensuring performance at low temperatures, as some of these materials are not suitable for such conditions. After a thorough analysis, we successfully identified a material that meets the requirements for both hydrogen compatibility and low-temperature performance, ensuring a secure and reliable solution.