JEC Group have brought together the international community of composites leaders and executives in our Composites Circle as an unique networking opportunity to meet with both peers and future partners.
Huntsman Advanced Materials tooling boards, which have already been used extensively in the international automotive industry, were recently specified in the construction of the k200, the ATR Group’s new micro-car.
(Published on January-February 2006 – JEC Magazine #22)
Super Light Cars (SLC), a subsidiary of the Italian company ATR Group, worked on the k200 model, a super-light vehicle made entirely from composite materials and specifically designed for the micro-car niche market. To build the models for the micro-car’s ten carbon-fibre chassis moulds and for all its bodywork and interior components, ATR Group technicians specified the BM 5055 epoxy tooling board from Huntsman Advanced Materials.
Once all the models of the chassis and bodywork components were milled from CAD data, several layers of fabric pre-impregnated with carbon fibre and epoxy resin were laid over the models by hand and autoclave cured at temperatures ranging from 60ºC to 190ºC, just enough to cure the resin and confer the required strength and toughness. The entire composite structure was then placed in a nylon vacuum bag and autoclaved again to compress all fabric layers evenly.
“The physical properties of this tooling board were particularly suitable for our technological process, especially the high-temperature and pressure stability, which are key requirements for the resincuring process,“ said Giulio Strambi, technical and operational manager at ATR Group. “Also, compared to other products on the market, we appreciated the ease of machining of the BM 5055 board and its good surface finish after CNC milling. This enabled us to drastically reduce the final hand-polishing operations and, subsequently, to speed up the entire manufacturing process. A series of tests carried out on the models made from BM 5055 boards allowed us to assess the thermal conductivity and expansion of this material, as well as its workability with our work station.”
For a period of one year, hundreds of models were made from the tooling board. The material’s stability certainly contributed to improving the production cycle and avoiding additional cost, as well as timeconsuming modifications to the model. In view of the satisfactory results, the BM 5055 board was included in the manufacturing process. The BM 5055 epoxy tooling board is ideal for hand laminating prepreg moulds and vacuum forming. It offers high dimensional stability, good temperature resistance, a smooth surface finish, a Shore strength of 75D, density ranging between 0.72 and 0.75g/cm3, and compressive strength of 50-55 MPa.