JEC COMPOSITES MAGAZINE - Issue #50 - July/August 2009 - 58

KNOW-HOW Compound Fatigue resistance Fatigue and creep performance can be influenced by the amount and length of reinforcing fibres. Dispersed strands create a dense structure of entanglements in the polymeric matrix. Because Lati HM products feature longer fibres than usual compounds based on industrial-grade chopped-strand master batches, the network is even denser, considerably improving: • the resistance to failure propagation throughout the matrix, as the longer fibres hinder development of the opening crack, providing an advantage both for the number of cycles to failure and the stress at break occurring during fatigue phenomena; • the stress distribution in static and dynamic applications. The difference in fatigue performance (load at break vs. cycles) is significant compared to other carbon-fibre-reinforced equivalents, and even amazing compared to PA66 reinforced with 50% glass fibre. …/… High-modulus carbon fibres in super-structural compounds injection-mouldable compounds that can be used in highly demanding projects where metal and composites cannot be used, or need to be replaced. Table 3: Tensile test (ASTM D256). Compound PA66 G/50 PA66 K/30 PPS G/40 PPS K/30 PPS – HM (ultra stiff) PPA G/50 PPA - HM (ultra stiff) PEEK G/40 PEEK K/30 Elastic modulus (MPa) 15,000 24,000 16,000 22,500 49,000 19,000 41,000 14,000 21,500 Load at break (MPa) 215 240 160 185 200 265 280 205 225 210 Elongation at break (%) 2.5 1.5 1.2 1 0.6 2 1.5 1.5 1.5 0.7 PEEK - HM (ultra stiff) 40,000 Many industrial sectors can benefit from the advantages of HM compounds: • aeronautics and military, • precision mechanics, • automation and robotics, • textile industry, • precision electric and electronics, • renewable energies and green solutions. Focus Fig. 4: Fatigue cycles to failure test. Lati S.p.A. is among the most important European Load at break A high carbon fibre content results in enhanced tensile modulus and compound resistance. Load at break is also significantly increased. Of course, outstanding stress at break is required if trouble-free metal replacement is the goal. HM compounds can reach tensile loads at break of 280 MPa (as per ISO-R-527) for the PPA-based grade – a value far beyond any optimistic expectation for injection-mouldable thermoplastic compounds. In fact, the best industrial structural compounds featuring 50 and 60% glass fibre can only come close to 220 MPa, with a much higher density. Many metal solutions, such as die cast, pot metal or zamak, are also unable to reach the performance of Lati HM. manufacturers of technical thermoplastics for engineering purposes. Our product range is made up of 2,500 fit-for-use formulations, according to the demand. The researched and internally developed materials are exported all over the world through its sales network and exploited in electric, electronic, industrial and automotive sector. The properties of these grades match the well-known advantages of injection moulding technology, i.e. high flexibility, low equipment costs and fast industrial implementation of new projects. Minor impact on environment and human health as well as easy disposal of scraps complete an already positive approach of this solution to the new challenges of modern engineering. Contact: marketing@it.lati.com More information: www.lati.com Conclusions Lati HM compounds set a new standard in structural thermoplastics by introducing to the market a new breed of 58 jec composites magazine / No50 July-August 2009

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JEC COMPOSITES MAGAZINE - Issue #50 - July/August 2009

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #50 - July/August 2009