Strain field of deep drawn knitted fabric reinforced thermoplastic composite sheets

Deep drawing of sheet metals has been widely investigated and practiced for the past five decades. Previous investigations on the deep drawing of sheet metals centered around the strain distribution of a formed cup. Recently, deep drawing of textile composites has been receiving the attention of researchers. This paper explores the strain distribution of deep drawn knitted fabric reinforced thermoplastic composite sheets. The strain field gives an indication of the location of severe strains and their magnitude. The method of composite sheet production, experimental procedure and processing of data are also described. It has been found that strains are generally higher in the course direction than in the wale direction. The variation of the punch profile has also been shown to alter the strain field.