Most machinists know the headaches of milling hard materials like titanium, inconels, and other durable alloys. Every pass is a battle between tool and workpiece. But what if you only needed to make one pass?
That’s the promise of near net-shape manufacturing. In initial production, whether it’s by casting, forging, or additive manufacturing, the part is made to be close in shape to the finished part, greatly reducing the amount of material to be machined off. It’s the ideal process to capture the potential of metal additive manufacturing while dealing with its resolution and surface finish limitations.
The Mazak VC-500AM is a 5-axis hybrid machine with an added cladding head. The cladding head performs direct metal deposition (DMD), and the cutter head has the same capabilities as any other 5 axis machine. Watch the video to see the machine in action.
This combined additive/subtractive capability allows you to perform, for example, a roughing operation, additive operation, and finishing operation in one setup. In the video above, the example is a drill head part. The round drill head is machined, then metal is built up in layers on that curved surface. After that, the cutter head comes back in and cuts the low-resolution added material. By combining the two processes into one setup, Mazak mitigates their drawbacks, such as material waste, difficulty cutting hard materials on the milling side, and low resolution and poor surface finish on the DMD side.
The obvious application for this machine is near net shape manufacturing for tough-to-machine materials. When finishing a printed feature, only 0.050” (1.25mm) needs to be removed. This has the potential to reduce costs in machining time, tool wear, and material.
Another interesting application is combining metals. A harder alloy can be printed in a layer onto a softer metal. This has implications for die work, in which the tool must have a hard, durable cutting edge, but must be ductile enough to handle the force without cracking. One company reported that they use this machine to experiment with coating softer 1018 steel with D2 tool steel. Rather than making the whole tool out of pricier D2, they can limit their expenditure to only where it needs it.
This machine is finding its home in the aerospace and defense industries, as they have the resources to invest in the machine. The additive technology also brings options for rework, and repairing expensive parts. Rather than scrapping an expensive part, new metal can be built up onto the part and machined back to good condition.
For more on near net shape manufacturing, check out VIDEO: Extremely Large Format 3D Metal Deposition from Gefertec.