Thermoset Composites

Newstamp, initially dedicated to the manufacture and stamping of metal parts, has recently begun to gain experience in the manufacture of composite parts by the Hand-lay up and infusion process. The acceptance of the market for this componentes and the will to embrace new challenges led us to create partnerships with two technical institutes to endow our development office with the capacity to design composite materials and tools for RTM-HP process.

We are a company that was born dedicated to the manufacture of metallic components and molds for stamping. The knowledge we have gained over more than 25 years in the manufacture of molds for sheet metal technology has facilitated the transfer of knowledge to the design and manufacture of molds for composite technology.

Hand-lay up is a manual process of stacking and impregnating the reinforcements. Successive layers of reinforcement are impregnated by hand. This process uses an open mold and is of all processes which offers parts with lower mechanical properties, with fiber fractions typically in the order of 25% -30%. The fact that only one mold is used implies that only one face has a good finishing. This process is used for small series, less than 1000 pieces per year.

This process uses the application of vacuum to produce components with good mechanical properties, fiber fractions in the order of 60% and less voids. The parts produced with this process have a good surface quality and and both sides can have it, because this process can use a close or an open mold, depending only on the specifications of the component to be manufactured. Vacuum molding allows series up to 5000 parts per year and is suitable for medium to large components.

Prepregs consist of fibers and resin. The reinforcements used can be glass fibers, carbon, aramid and even combined fabrics, while the matrix is mostly used epoxy resins. These are considered semi-products and used in demanding applications such as the aeronautical industry, automotive and high performance sports. These semi-products are known for their good processing characteristics, of which the most important are the maneuverability, self-adhesion between layers, ease of positioning and good conformability to mold curvatures. For the transformation of these semi-products are used more technologically advanced processes, such as the use of autoclave or RTM-HP.

The HP-RTM process is the most technologically advanced compared with the process described before and allows the reduction of cycle times, which can go from 2 hours to 3 minutes, depending on the size and complexity of the parts and systems used. In this manufacturing method is used positive and negative molds, the resin is injected at pressures around 30 bar. The produced parts, generally médium size, have very good mechanical properties and excellent surface finishing in both sides.