LIGHTWEIGHT MANUFACTURING In essence, TFP increases the level


of automation associated with carbon fi bre reinforced polymers (CRFP) manufacture whilst also drastically reducing material wastage. Although TFP was an attractive option at inception, it initially failed to deliver the productivity levels required to become a mainstream technique. Updates to the process promise to solve these concerns and adoption is already becoming more widespread across aerospace, defence, medical, clean energy, smart clothing and sports equipment manufacturers. TFP off ers virtually limitless freedom


in terms of applications and brings composites’ benefi ts within tangible reach. For example, CRFP can be 10 times stronger than steel while weighing a fi fth as much. This translates into major economy savings for automotive and aerospace, in particular. “Independent studies show that a 10% weight reduction can result in a 6-8% improvement in fuel economy,” explains Sobizack. “The savings are more marked in aerospace, where according to a major airline operator, every kilo taken from its fl eet of aircraft saves the company US$20,000 per year. Of course, these benefi ts are perfectly aligned with the requirement for ever- reducing emissions.” One of the most obvious downsides


of carbon fi bre is cost. Using traditional manufacturing techniques, components can cost 20 times that of an equivalent steel part. It is also unsuitable for complex or load-bearing shapes: the physical properties of carbon fi bres are immensely strong only when forces are applied along their length. Due to this, carbon fi bre layers are applied at diff erent angles to build up


Elemental wheel arch and suspension


a component’s strength in multiple directions, which is challenging for complex shapes and is extremely labour-intensive. Each layer is cut from sheets of carbon fi bre, which is often pre-impregnated with the matrix resin (so-called ‘prepreg’), leading to high wastage of a costly material – rates of anything up to 60% in some cases. TFP directly addresses these concerns. TFP utilises embroidery-based


techniques to manufacture composites. Unlike traditional laminate construction methods, TFP begins with the reinforcement material in its strongest and generally most aff ordable form: dry fi bres. With no plies to prepare before creating the preform, the cutting stage is entirely eliminated. By laying fi bres in place and stitching periodically to the base layer, waste materials are reduced to the extent that the material scrap rate on a TFP part is in the region of 1 or 2%. “One of the main advantages of TFP


The RP1 is among the fi rst in the car industry to use this technology


is that individual fi bres can be placed exactly as required, without the need


for multiple layers, giving designers almost limitless


freedom to optimise


a structure based on the forces acting upon it,” notes Melanie Hoerr, ZSK’s technical embroidery manager. “Its level of automation makes TFP entirely repeatable which minimises variation in dimension, density or fi bre position, and eliminates human error, ensuring consistent structural performance. “Using this process, layers of thread can be deposited without stitching them to the base material at regular intervals,” she continues. “To maintain position, layers can be anchored at a few key points, which enables the preform to deform into complex 3D shapes when pressed into a mould, resulting in geometrics that would be almost impossible to replicate using alternative automated methods. This enables carbon fi bre to become a cost-eff ective option for manufacturers designing lightweight, load-bearing components such as suspension components, body


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