Rapid tooling, cost reductions are key in die casting prize winners

Die casters continue to surprise with their increasingly innovative designs. Take the case of Contech Casting LLC, Southfield, Mich., and its new automotive AWD clutch housing. The company successfully converted a multi-step forged steel housing to an aluminum squeeze casting, thereby building the part in fewer steps and with optimal solidification. The resulting mass reduction gives better vehicle fuel efficiency and reduces inertia, which improves all-wheel-drive engagement-response times. This company, in fact, was one of several winners in the recent North American Die Casting Association’s (NADCA) International Die Casting Design Competition. Judges evaluated submissions for design quality, cost reduction, and contribution to the growing casting market. The eight winners and two honorable mentions were showcased at the Cast in North America Pavilion at CastExpo’10 Orlando, Fla., in March. Other examples of winning parts come from: A power-conditioner chassis by Twin City Die Castings Co., Minneapolis. Die casting aluminum slashed the costs associated with machining the chassis from roughly shaped ingots. In addition, flow simulation helped develop a gating system for the efficient filling of the part’s many fins and tall bosses. And the use of rapid tooling let the company complete the three-slide die casting in just over eight weeks. An amplifier body from Aselsan in Turkey. To make this part, the company first considered extrusion and investment casting. But this would have required extensive machining to provide fine functional geometry and efficient heat dissipation. Worse yet, it was expensive to waterproof the extrusions. The fins had openings that passed through the entire part, which presented a challenge to successfully die cast. However, a well-planned four-slide die design produced a high-quality aluminum die casting. Other winners include: A black housing for a rugged tablet PC for military and industrial uses that contains an aluminum die cast heat sink embedded in another magnesium die casting; a 54 × 52-in. die-cast magnesium lift gate that replaces a stamped steel assembly; and a zinc die-cast flange, originally made from machined hot roll steel, which serves as the base of a flat-panel TV swivel. Sources: • North American Die Casting Association, Wheeling, Ill., www.diecasting.org• For information on how to enter the competition in 2011, visit www.diecastingdesign.org/castings/competition• To read about NADCA’s new HyperCasting technique, visit http://tinyurl.com/36tv2s5