R. Lizarralde, X. Alzaga, A. Gandarias, O. Zelaieta, Ideko Koop.E., Elgoibar, Spain

Summary:

Although magnesium alloys are easily machined with HSC parameters, fire and explosions hazards are likely to happen due to the characteristics of the material. Current machining processes have solved somehow these risks with the employment of cutting fluids and automatic fire extinguishers. However, the oily chips produced can not be recovered and recycled, and must be treated like waste disposal.

Internal chip extraction through all the turning system (tool, tool holder and spindle) is a technology for machines and cutting tools of the future. This technology offers great advantages in comparison with the conventional machining processes based on cutting fluids in terms of safety, environmental issues and cost effectiveness. The advantages and characteristics of this technology will be described in this paper. A whole description of the system set up, from the cutting edge to the chip extracting system, will be also presented, describing the characteristics of each of the components of this new machining concept for machining magnesium parts. Critical aspects like chip morphology and cutting conditions as influence parameters in the quantity of evacuated chips will be remarked.

Finally, the technology has been validated with the results obtained from the machining of an AZ91 cloutch housing and an AM60 piston, reaching the industry quality requirements. These tests permit an approach of this technology to industrial applications in a close future with the development of complete machining systems.