TPT September 2024

CUTTING TECHNOLOGY, SAWING & SAW BLADES

Physical vapour deposition coatings: innovation and efficiency in steel tube cutting

Knoop penetrator and comparing H/E and H3/E2 ratios derived from nanoindentation. • Microstructural analysis: conducted using scanning electron microscopy (SEM) and EDS microprobe to determine composition and variations in the coatings. • Observation of coated tooth geometries and quantification of the “uncoated” surface fraction: analysed using SEM and image analysis. After developing a type of coating, field testing begins to assess the value of the study and the improvements it has brought. The hardness of PVD varies depending on the type of coating, but can triple the HV values compared to hardened steel, reaching values between 1600 and 1800HV. Blade performance can improve by 30 per cent to five times, depending on cutting parameters, particularly cutting speed. Recently, Moreschi Srl invested in a new coating plant. This plant has doubled the companies’ coating capacity. In addition, it allows coating blades up to 1,400mm in diameter. It is the only PLATIT system of such dimensions in Europe, bringing new possibilities for innovation in the large diameter tube cutting sector. “Our goal is to provide customised solutions to meet our customers’ needs. For this reason, we have decided to invest in the entire production process, including PVD coating. Continuous research and close collaboration with universities and our clients allow us to constantly evolve and offer not only innovative, but also unique solutions,” said Mattia Moreschi, head of the purchasing department and second generation management of the company. PVD represents an indispensable technology for the steel tube cutting sector, offering advanced solutions to improve the durability and performance of tools. Thanks to continuous research and development, Moreschi Srl’s PVD coatings can meet the increasing demands for productivity and quality while simultaneously reducing operational costs.

PHYSICAL vapour deposition (PVD) coatings represent an advanced technology for improving the performance of cutting tools. These surface metallic coatings, with thicknesses ranging from a few tenths of a micron to several microns, are essential for all tools subject to wear. In the case of circular saw blades, the main goal of PVD is to extend the blade lifespan and maintain their original geometry while ensuring optimal performance. PVD is used on various materials depending on specific needs. For steel tubes, there are various types of coatings developed to meet different market demands. For tubes, it is essential not only to extend the life of tools to avoid costly machine downtime, but also to achieve high cutting speeds. Tube manufacturers often require performance that exceeds normal standards, especially in flying cutting, where the saw must operate at high speeds without compromising efficiency. The demand for high productivity in both static and flying cutting has driven saw manufacturers to continuously improve their technologies, focusing especially on the coating. This development is supported by research centres that help create coatings with the ideal characteristics for tube cutting. Every year, Moreschi Srl collaborates with Italian universities on development projects to improve their PVD coatings. In research, the criteria to consider are numerous and complex,

The latest PVD coatings process allows blades of up to 1,400mm

including cutting parameters (type of plant, maintenance status, cutting speed and feed rate, type of lubrication, cutting times, operator skill level) and the parameters of PVD plants, which are highly technological and subject to rigorous controls and tests. Research on PVD coatings focuses on characterising mechanical, compositional and microstructural properties. The aspects evaluated include: • Hardness and elastic modulus: measured by nanoindentation according to ASTM E2546-15. • Adhesion: qualitatively assessed through HRC indentation (VDI 3198) and quantitatively through nano scratch. • Coefficient of friction and wear resistance: measured in sliding conditions with pin-on-disc tribological testing at room temperature, following ASTM G-99. • Fracture toughness: quantified by measuring radial cracks with a Vickers/

PVD coatings represent an advanced technology for improving the performance of cutting tools

Moreschi Srl

www.moreschi.eu

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SEPTEMBER 2024