Melt extraction of short metallic filaments: Fibre formation process revisited

This article presents experimental results of the extraction of metallic fibres from the surface of a melt pool. A low-melting alloy was used in a model facility to produce filaments of equal length. Operational parameters such as wheel speed and feed rate were varied to yield thin fibres. In contradiction to the commonly accepted tendencies, the analysis of the fibre cross-section showed only a relatively small decrease with an increase in wheel speed. High-speed video recording of the meniscus region was employed to investigate fibre formation. The recordings revealed that short fibres may only be produced during duty cycles. As available literature is limited for explanation of the observations, a simple model was developed.