Advanced machinery relies on precision cutting and grinding tools to produce accurate components such as gear teeth and turbine shafts used in cars, planes, and wind turbines. These tools must withstand extreme loads, friction, heat, and wear while maintaining their exact shape.
Tiny surface defects can cause components to wear out, crack, or fail much sooner than smooth surfaces. As a result, polishing or coatings are used to improve performance and durability. As demand increases for higher precision, longer tool life, and greater sustainability, new polishing and coating techniques are needed to support the next generation of advanced machinery.
As part of AMPI’s mission to strengthen the UK’s advanced machinery sector, the University of Manchester investigated improved techniques for polishing and coatings. The workstream focused particularly on how electrochemical techniques, notably Electrolytic Plasma Polishing (EPPo), could help create more precise, durable, and sustainable tooling.
EPPo is a non-contact surface-finishing process that involves dipping a metal into a liquid electrolyte and applying a voltage. This creates a thin layer of microscopic plasma bubbles at the surface, which gently removes raised spots and surface roughness. The process polishes the metal evenly and without mechanical contact, making it ideal for complex or delicate tool geometries.
The research team explored several interconnected industrial challenges around EPPo. These included how to scale EPPo for industrial use, how to use it as a precursor to applying coatings, how to measure and control tool-edge geometry more precisely when using EPPo, and how to reduce waste and recover valuable materials from polishing processes.
The project delivered tangible benefits by advancing understanding of electrochemical polishing and translating academic insight into practical industrial capability for three manufacturing companies in Greater Manchester and West Yorkshire.
Bury-based Wallwork Heat Treatment provides EPPo services to machinery customers. Through engagement with the programme, the company improved the scalability and sustainability of its EPPo capabilities by accessing greener electrolyte formulations, new tools for extending electrolyte life, and a technique for applying electrical energy in controlled bursts. This approach is more efficient than their previous method and improves surface finishes.
For Dathan Tool & Gauge, based near Huddersfield, the work demonstrated how EPPo, supported by purpose-built digital measurement tools, can precisely control cutting-tool edge geometry. This improves tool resistance to chipping and lays the groundwork for the company to develop longer-lasting, higher-precision tooling.
For Holdson, an electrochemical polishing technology company, the team identified routes to making electropolishing more sustainable. This included recovering titanium from electrolytes in a reusable form, reducing environmental impact and recovering value from existing processes.
Across these projects, the Manchester team advanced understanding of EPPo for precision tooling, improving surface quality and making the process more sustainable.
Not only does this strengthen the capabilities of specialist UK machinery small and medium-sized enterprises, it also benefits the manufacturing companies they supply. These companies gain access to higher-quality, more durable tools that reduce costs and improve product performance.
