Prototyping Past 1,000 mph
When setting out to build a car capable of surpassing 1,000 mph, strong but light materials are required for a vehicle to move faster than a bullet fired from a gun (~900 mph). In fact, the Bloodhound supersonic car (bloodhoundssc.com) looks a little like a bullet. The U.K.-based public-private partnership’s mission statement: “Confront the impossible and overcome it using Science Engineering Technology and Mathematics.” No land vehicle has ever gone as fast as they hope to in 2015. The current record: 763 mph, set in 1997 with Andy Green behind the wheel. He is slated to be the Bloodhound driver, as well.
An example of the engineering going into the Bloodhound is the titanium nose that’s been prototyped for the car by British engineering company Renishaw (renishaw.com). Although the vehicle has a carbon fiber and titanium body, it still weighs more than 7 tons. Still, saving weight is a key, which is why the nose is titanium, which is light and capable of handling the forces as high as 4,915 lb/ft2 it will face.
Renishaw produced the tip with its AM250 additive manufacturing system, which uses precisely controlled laser technology to melt thin layers of titanium powder that hardens to form the component.
Explaining the benefit of the additive manufacturing approach, Dan Johns, Bloodhound lead engineer for materials, processes and technologies, said, “We believe the key benefit of using an additive manufacturing process to produce the nose tip is the ability to create a hollow, but highly rigid titanium structure, and to vary the wall thickness of the tip to minimize weight.” He added, “To machine this component conventionally would be extremely challenging, result in design compromises, and waste as much as 95% of the expensive raw material.”
The team plans to continue to use the Renishaw equipment for additional work on the car.
The Bloodhound engines produce more than 135,000 hp. There are a EUROJET EJ200 turbofan jet, a hybrid rocket with an average thrust of 111 kN, and a 750-hp V8 Cosworth CA2010 Formula 1 engine, which is being used as an auxiliary power unit. The acceleration from 0-1,000 mph is anticipated to take 42 seconds.
Renishaw created a prototype nose tip for the Bloodhound supersonic car slated to top 1,000 mph.
CNC Service Offers Hard Metal Options
Proto Labs’ (protolabs.com) quick-turn CNC machining service now offers the ability to rapidly produce prototypes from hard metals. Upload 3D CAD models at Firstcut.com, select stainless steel (304/304L or 316/216L) or steel (1018 or 4140), and get quick turnaround of CNC-machined parts in prototype quantities. These new hard materials complement Proto Labs’ existing selection of soft metals (magnesium, copper, brass and aluminum), as well as more than 30 types of engineering-grade plastics (they have a fast injection molding service, too).
Proto Labs now provides prototype parts machined from stainless steel.