As a result of the environmental and economic conditions, the issue of developing new composite materials gains importance. Despite their mechanical characteristics in the industrial fields, resins such as epoxy, polyester and fibers such as glass, carbon, aramid, which are widely used in the fiber reinforced composite structures, pose an environmental risk since they are hard to recycle. The issue of natural fibers is one of the focal points of the academic researches as they provide cost advantages in recycling.
Assoc. Prof. Dr. Levent Önal from the Erciyes University, Department of Textile Engineering, who has conducted researches on the issue, has completed his work on ‘Environmentally Friendly Composite Production Methods and Their Potential Use in the Automotive Industry. Önal, who produced - using the jute fiber wastes, used in the production of machine made carpets - natural composite panel for the automotive industry, was granted the first prize in the field of ‘Vehicle Textiles and Filtration’ at the 4th R&D Project Market Summit, held by Uludağ Textile Exporters’ Union. As Textil Dünyası, we received information from Assoc. Prof. Dr. Levent Önal, about the details of his work, which is important both economically and environmentally.
Production for the Automotive Industry
Levent Önal stated that in the last 20 years, the use of recyclable materials, particularly the natural fibers, in the composite industry and environmental awareness have gained importance. Önal added that several , which he follows from the literature, are carried out in this field. Önal remarked that the idea of focusing on this field came to his mind when he was conducting a research on the biologically degradable composite materials in the Composite Research Centre of Nottingham Univesity, where he attended for post-doctoral training in 2004. “After returning to Turkey, I was searching for new studies to carry out and I had the chance to receive information about the use of jute and waste amounts during my technical visitation to Saray Halı. Later, with the support of Saray Halı, I wrote my TÜBİTAK research project in 2005 and the process began as I received research support from TÜBİTAK,” said Önal. Stating that since automotive sector has been selected as the basiz usage area, they’ve adopted the production processes used in the automotive industry, Önal reminded that they produce composite panels with the method of Compression Molding and Vacuum Infusion
Önal stated that his first project in this field was supported by TÜBİTAK with a budget of TRY 88,000 in 2008. “I completed the project in 2009 and undertook a postgraduate project - as a supporting project - from the Erciyes University. In the Spring of 2012 I offered a new TÜBİTAK 1001 project. It is now being examined. We offered the new project together with Assoc. Prof. Dr. Mehmet Hançer from the Department of Material Engineering and Recep Güneş, Assistand Professor Doctor from the Department of Mechanical Engineering. A doctoral student and a graduate student are now conducting their studies in the project team,” said Önal.
Önal attributes the driving factor in using natural fibers in the automotive industry to the requirement, specified in the ELV law (End of Life Vehicles) enacted by the European Commission in 2000, of manufacturing the vehicles, produced in the EU countries, as biodegradable or recycable by 95 percent as of 2015. Önal reminded that the studies on this isuue will continue. Önal emphasized that the studies will gain speed with the decisions taken by the European Union. “The jute yarn – between 7 and 11 – used in the carpets is damaged and dispersed during the production process. The jute fringes ocurring 10-15 cm arounf the carpet are cut in the prodcution process. We aim to make use of this waste material for the economy and to be used in the automotive industry,” said Önal.
Önal argued that due to the storage costs, the waste jute is bartered away and he stated that jute is mixed with polypropylene in the new material that is produced. “In the samples we produce, we use textile surfaces of nearly 300 gr/m,” said Önal and added; “The cost of the raw waste is 7-9 kr/kg and the cost of the waste, when processed as needle felt, is around 17 kr. So it is incomparably cheap. However it is a little bit difficult to calculate the unit cost because the cost of creating a composite panel changes according to the type of the resin and the mold shape of the final product.”
Automobile Giants Prefer Natural Fiber SupportedComposites
Önal stated that all the leading automobile manufacturers including BMW, Mercedes, Volkswagen and Toyoto use natural fiber supported composites in the production of automobiles of D segment. “We expect that as a result of the decline in the costs of these materials, they will be used in the automobiles of C segment,” said Önal who also gave information about the substitutue products. “The natural fiber supported products used in the automobiles are imported from the foreign countries. Especially the ones supported by wood fiber have started to be produced by a special company in Turkey. We’re doing interviews with two textile enterprises on the production of pre-shape used in the composite production,” said Önal.
Önal made evaluations regarding the other substitute products and stated that the most important advantage of a material is its low cost. Önal added that the disadvantage of the material that is also used as an effective solution in sound insulation is the fact that it has lower technical features compared with the glass fiber widely used in trade and that the dehumidification characteristics of natural fibers are too high to be compared with the synthetic fibers.
Önal emphasized that the product’s usage area expands and that it is hard to reach the product’s usage information in Turkey. Önal finished by saying; “Data flow within the automotive sector is just like a closed box due to the big production quantities. In order to understand the usage size and conditions, it would be a better method to deal with the parts they are used in an automobile. At this point, the net and effective use of natural fiber composites takes place in the iner-side panels of the doors. Besides the materials is used as coating on gear shift knob, steer wheel and the front console. The decisions taken by the European Union regarding the materials used in the automotive sector are the driving force for the Turkish manufacturers to enter this field.”
