Manufacturing by laser welding, and ultrasound measurement, on Hydrogen container

Purpose and goal:

In this feasibility study, joining for industrial production of a new type of lightweight structure will be developed, with the aim of using this as storage unit for hydrogen gas. Special steels are used and therefore alloying elements need to be added to maintain the material properties in the welds. The goals for this development project are largely met, but many aspects remain before industrialization can take place.

Here, a new ultrasound-based measurement method for monitoring of the complex joints has been developed, showing high potential but also needs further development. Expected results and effects:

A new joining method has been developed, here for joining special stainless steel and a complex geometry. It still needs some further development but shows good opportunities for implementation when certain aspects have been developed. Ultrasonic technology for monitoring welds has also been developed and shows good potential, but it also needs to be further developed with, e.g. machine learning, before it can be implemented in practice.

The new structure has been successfully combined with good microstructure and topography in joints, without significant distortion. Approach and implementation:

A purpose-made strip steel has been produced and specially designed shapes for new lightweight structure has been cut out of these sheets, joining fixtures developed, special paste for adding additives in the joint before fixturing and welding. During iterative joining steps special high-speed imaging has been applied to tailor the process for the complex joints, followed by microstructural analysis and ultrasonic measurement.