H² Manufacturing: Hybrid-Hybrid machining of next generation aerospace materials

This EPSRC funded project is a unique collaboration between academic and industrial partners with the final goal of making an industrially relevant technological breakthrough in the manufacture of aerospace components.

The project outcomes will directly benefit:

• High tech aerospace component manufacturers
• Tool manufacturers

Project Aim:

Develop a robust industrially relevant Hybrid-Hybrid machining process, resulting in a step change in improving machining efficiency and surface integrity of particulate metal-matrix composite components.

There are two major types of research objectives

FUNDAMENTAL:

(1) Develop fundamental understanding of the multi-energy field interactions of laser, ultrasonic vibrations and mechanical deformations.

(2) Develop framework for computational assessment of deformations, residual stress and microstructural changes as a result of imposed multi-field machining conditions.

PRACTICAL:

(3) Design, develop and implement an optimal Laser-Ultrasonic Assisted Machining prototype for CNC machines.

(4) Carry out comparative: machining quality studies, cost/time analysis, efficiency estimates of the developed Hybrid-Hybrid system.

Essentially, a thorough understanding of the complex interactions between different energy sources is warranted, since one source could negatively affect another.

Summary

The application of laser assisted machining/processing has shown promise in reducing tool wear in the machining of difficult-to-machine aerospace materials, such as, metal matrix composites (MMCs). On the other hand, ultrasonically assisted machining has been successfully used to demonstrate essential reductions in cutting forces with an improvement of machined surface quality. This project is a fundamental research programme that aims to comprehensively study the two techniques in combination with a clear route to implementation. Through the transition to hybrid-hybrid manufacturing processes such as the one proposed, UK industries will be able to meet the growing needs of present and future sectors/customers by efficient and sustainable resource usage in the manufacture of future aerospace materials.

The research will focus on the influence of the thermal field-ultrasonic vibrations-mechanical deformation on the MMC material taking into consideration the initial underlying micro-structure of the material. Special attention will be paid to dynamic recrystallization and grain growth of the metallic matrix material due to the influence of the imposed thermal field and deformation-rates (due to machining).

In parallel, a laser-ultrasonically assisted machining system will be designed, developed and installed on an existing CNC machine, with the aim of cutting without coolants, using less force and machining-induced damage. Machining studies will be conducted at industrially relevant machining conditions. Comparisons will be drawn with current practice for best machining outcomes. It is expected that the new hybrid-hybrid manufacture will lead to less machining forces with reduced tool wear and post machining (tensile) residual stresses.

Finally, several case studies will be conducted with the aim of developing next generation tools for optimal manufacture.

Project Partners

Publications from the project

1. Enhanced machinability of SiC-reinforced metal-matrix composite with hybrid turning, W Bai, A Roy, R Sun, VV Silberschmidt, Journal of Materials Processing Technology 268, 149-161 (2019) OPEN ACCESS
2. A crystal-plasticity model of extruded AM30 magnesium alloy, R Zhou, A Roy, VV Silberschmidt, Computational Materials Science, accepted July 2019 OPEN ACCESS