±¬ÁÏTV

Jozef McGowan presented this work at the Plansee Seminar on the examination of tool wear seen when milling titanium samples. Tools were used to machine various Ti parts, then sectioned and polished, and finally examined under scanning electron microscope to observe the wear. In doing so relevant data was gained about how the tool degrades.

When milling titanium alloys, cutting tools tend to degrade rapidly, often with little visible wear before sudden failure occurs. Although tool wear has been extensively studied in machining operations, such as turning, milling has remained comparatively under investigated. At the same time, new processing routes for titanium components, such as field assisted sintering technology (FAST) or wire arc additive manufacturing (WAAM), are becoming increasingly common. Jozef’s research focuses on how these different processing routes influence tool wear during milling.

One method used to investigate the mechanisms active in the early stages of machining, before extensive plastic deformation of the tool, was by conducting milling tests for approximately eight minutes. At this point, the tools were removed, labelled, and examined. Analysis revealed a layer of adhered titanium alloy at the tool:workpiece interface, similar to observations made in turning. Further inspection suggested a possible depletion of cobalt (the binder phase in the tool material) in the immediate area of the tool, behind the adhered titanium layer, indicating potential outward diffusion. These findings remained constant across the samples produced using both conventional forging, and FAST. 

Carrying out this project was my first time writing a paper and the work I produced was the first I presented at a conference. As such it proved a very useful first step into my PhD, giving me valuable writing, presenting and most importantly research skills

Jozef McGowan

Titanium and titanium alloys are widely used across aerospace and biomedical sectors, used in components such as landing gear, aero-engines and medical implants. These components often require large amounts of machining with up to 95% of the bulk material being removed in some cases, meaning machining and tooling is by far the most expensive processing step. As a result, increasing tool life by any amount can decrease manufacturing costs greatly. Jozef’s work centres on examining tool wear with the goal of decreasing it, as well as examining machined titanium components to examine the microstructural damage, so as to potentially decrease the amount of machining required.  

Equipment Used

• Scanning Electron Microscope and metallographic preparation at Sandvik.

• X-EDS at Sorby Centre ±¬ÁÏTV

Biography

Jozef is a 2nd year EngD student at the ±¬ÁÏTV. His work is sponsored by Sandvik Coromant and focuses on understanding the machinability of titanium alloy components from a range of processing routes to inform tooling solutions for next-generation closed loop recycling technologies.
He graduated from the ±¬ÁÏTV in 2023 with a BEng in Aerospace Engineering. His interest in materials science and sustainability was peaked whilst working on various materials and machining modules as well as his final year project, which focused on designing a more sustainable ethically sourced Ni-based superalloy for aerospace applications.