Robot in Additive Manufacturing Applying Bronze to Rocket Engine

The integration of additive and subtractive enables product designers to pursue product enhancements that could not be manufactured in any other process. At the same time, this combination is reducing the time it takes to prepare for parts production, including acquiring the necessary tooling. Additionally, it is trimming costs associated with tooling and conserving a lot of expensive raw materials typically machined away in strictly subtractive operations.

It’s no wonder manufacturers are taking a greater interest in integrating the technologies.

Machine tool builder DMG Mori recently began incorporating additive manufacturing (AM) to metal-cutting processes that traditionally only used subtractive operations.

The hybrid manufacturing machines from DMG Mori allow the integration of additive (deposition) and various types of subtractive operations without removing the part from the machine. The machines have higher deposition rates and larger envelopes to enable deposition and machining of larger parts.

In one example of hybrid manufacturing, metal AM technology is paired with subtractive technology, enabling each process to work together on the same machine and same part.

The latest iteration here is building hybrids with larger envelopes—that support greater deposition rates and require more powerful lasers, DMG Mori Advanced Solutions CTO Gregory Hyatt said.

Such machines can be leveraged to deposit multiple alloys with alacrity.

“For example, when the workpiece requires a bi-metallic build like Inconel and copper for a rocket nozzle, we can deposit these two compatible alloys in the same build,” he said. This development of methods has also spurred innovation in other areas such as programmable fixturing, laser hardening and subtractive manufacturing processes such as ultrasonic grinding.

“Deposition exerts minimal forces on the part, so minimal support from a fixture is required, but in order to machine without chatter, the need for a fixture returns. DMG Mori has developed programmable and flexible fixturing techniques, which replace the conventional fixture, to support the parts being machined,” Hyatt said.

It has also greatly reduced part-production prep time, the lead time to acquire the necessary tooling and the cost associated with the tooling, he added.

Read more: How AM can complement conventional machining