The high investment cost and long lead-time to design and manufacture a forming tool is a major obstacle for local manufacturing of products in sheet metal. To minimize resource consumption large efforts have been made in order to increase material efficiency by reducing the thickness of the sheet and move towards production methods with less scrap percentage. Nevertheless, the scrap portion is still high, in the automotive industry often as high as 50%. This paper discuss the possibilities of introducing knitting of metal wire into metal engineering industry to manufacture scrap free, light-weight, three dimensional components in metal. Knitting could be a way of obtaining material efficient production within metal engineering industry especially for small and medium sized enterprises, SME. A knitting machine is able to produce large amounts of products at low price with moderate investments costs. For certain products knitting offer a simplified production of ready formed, 3D components. Experiments with knitting stainless steel wire were performed in order to establish the possibilities and limits of knitting today as well as identify development possibilities. The experiments covered improving the stiffness of the metal knit-wear by using different knitting techniques as well as introducing subsequent manufacturing steps such as surface treatment and joining. Demonstrators where produced for a number of geometries; squares, rectangles, boxes, hour-glass like in 2D and tubular, conical and T-tube shape in 3D. For two geometries produced with knitting and sheet metal forming, the material efficiency was compared. The first geometry used 32 % less material in the knitted product compared to the sheet metal component. The second geometry used 72 % less material in the knitted component compared to the sheet metal component. However, properties like strength and stiffness will be considerable less for a knitted component than for a sheet metal component. Today applications for the knitted materials have to be chosen carefully to take advantage of the potential of the material. With further development of both the knitting technique and subsequent operations the process will open new possibilities of material efficient and light-weight manufacturing.
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