Burning hard metal: Drilling Performance

The GE Blue Arc machining process that, according to GE, “cuts through titanium like a hot knife through butter,” has been in development for years, but it’s taken a large step closer to being put into commercial production.

GE has partnered with Mitsui Seiki Kogyo Co. Ltd. to develop a 5-axis horizontal machining center with a Blue Arc head attached. Built at Mitsui Seiki’s headquarters, outside of Tokyo, the prototype machine is now at GE’s global research facility in Van Buren Township, Mich.

The Blue Arc electrode can be shaped for optimal drilling, milling and grinding. Image courtesy of Mitsui Seiki USA.

Blue Arc is an electro-erosion metal-removal method designed to rough extremely challenging-to-machine alloys, such as aerospace-grade titanium and nickel-base superalloys, about four to five times faster than conventional machining, according to Scott Walker, president of Mitsui Seiki USA Inc. Using high-amperage, low-voltage electrical energy, sparks and heat are created between the electrode tool and the workpiece. During the electrical-arcing activity, portions of the workpiece are melted and the molten material is quickly flushed away with high-pressure coolant. The process exerts low force, permitting higher feeds and speeds.

Walker told CTE that while there may be three or four machining centers around the world that have been retrofitted to work with Blue Arc technology, the Mitsui Seiki HMC “is the first new machine with blue arc on it in the world [that’s] designed and built to work with this technology.” It’s a machine that’s suitable for production purposes and can run for 75,000 hours, he added.