Octavio Pereira

A cryo lubri-coolant approach for finish milling of aeronautical hard-to-cut materials

Use of heat-resistant alloys is growing worldwide in aeronautical turbo-machinery industry. One of the most used materials is Inconel 718. This material is featured by high resistance to corrosion and oxidation while keeping good mechanical properties at high temperature. However, low machinability of this material results in poor material removal rates and premature tool wear, among other drawbacks. Consequently, mineral cutting fluids are injected in the cutting zone in order to improve machining. However, todays environmental consciousness leads us to propose the cryoMQL technology as an ecological alternative. In order to achieve better results when milling Inconel 718, a CO2 cryogenic regulation system and a nozzle adaptor have been developed to use cryoMQL and a comparative analysis is performed with regard to other coolant alternatives.

Comparison of Flank Super Abrasive Machining vs. Flank Milling on Inconel® 718 Surfaces

Thermoresistant superalloys present many challenges in terms of machinability, which leads to finding new alternatives to conventional manufacturing processes. In order to face this issue, super abrasive machining (SAM) is presented as a solution due to the fact that it combines the advantages of the use of grinding tools with milling feed rates. This technique is commonly used for finishing operations. Nevertheless, this work analyses the feasibility of this technique for roughing operations. In order to verify the adequacy of this new technique as an alternative to conventional process for roughing operations, five slots were performed in Inconel® 718 using flank SAM and flank milling. The results showed that flank SAM implies a suitable and controllable process to improve the manufacture of high added value components made by nickel-based superalloys in terms of roughness, microhardness, white layer, and residual stresses.