One solution is the use of thermoplastic composites that can perform with at least the same assurance as traditional metals and thermosets. A case in point is Tri-Mack Plastics Manufacturing Corporation, a moulder of high temperature engineering thermoplastics, based in the US, which has selected Victrex PEEK polymer for the production of brackets for use in structural aircraft applications. Victrex PEEK polymer has in fact been used in injection-moulded aerospace components for more than 25 years, and Tri-Mack chose the material on account of its excellent technical features and proven track record. The company then proceeded to develop a Victrex PEEK manufacturing capability. Based on current fuel prices and studies, reducing the weight of a short-range aircraft by 1kg can save airlines up to US$100 in annual fuel costs. “Assuming that the composite brackets can remove 100kg of weight, an airline with 500 short-range aircraft could save up to $5m per year in fuel costs by making the switch from metal,” explained Ralf Weidig, composites business leader for Victrex. The use of a carbon fibre composite made with Victrex PEEK polymer results in a weight savings of up to 70%, compared to the use metals such as stainless steel, aluminium, and titanium. In addition, the innovative composite manufacturing process used by Tri-Mack results in faster part manufacturing cycle times, when compared to thermosets. “Thermoset composite parts typically take several hours to complete,” said Tom Kneath, director of sales & marketing at Tri-Mack. “The Victrex PEEK thermoplastic composite brackets have manufacturing cycle times measured in minutes. That speed, paired with the ability to recycle the material for other applications, takes us to a whole new level of processing efficiency that isn't achievable with thermosets.” Component integrity is also critical for keeping aircraft in service and minimising maintenance and downtime. Thermoplastic composites made from Victrex PEEK can provide chemical and corrosion resistance to jet fuel, hydraulic fluid, de-icing solution, salt, steam, water and other commonly used service fluids that would typically undermine the longevity of metals. “Victrex PEEK composites can also offer between four and five times higher fatigue strength, specific stiffness, and specific strength when compared to traditional metals such as aluminium,” said Weidig. "These mechanical properties, along with vibration and noise dampening improvements, make Victrex PEEK composites an attractive and viable solution for engineers looking to replace heavy metals and thermosets.” www.victrex.com
