This part of ISO 25239 specifies a method for determining the capability of a manufacturer to use the friction stir welding (FSW) process for the production of products of the specified quality. It specifies quality requirements, but does not assign those requirements to any specific product group. In this part of ISO 25239, the term “aluminium” refers to aluminium and its alloys. This part of ISO 25239 does not apply to friction stir spot welding.