We understand that the life of tools is important – especially reliable life – to avoid time lost and excessive wear.
However, more important than tool life is performance. Allowing them to work faster, harder, hotter and reaching higher metal removal rates (MRR) is where there’s scope to reduce the cost of goods. Especially when using CNC machines, reducing the time it takes to make goods will reduce your overall manufacturing costs. We tend to focus on tool life because it’s much easier to measure.
How PVD coating can improve performance
It’s common knowledge in the manufacturing industry that post-manufacture coating of cutting tools makes them perform better in many applications. They can also be re-serviced by re-grinding and re-coating multiple times to extend their useful life – and sometimes to re-purpose them for a different application or material.
What’s not common knowledge is that some coatings can make performance worse, or that the benefits of coatings can be greatly enhanced by improving the cutting tool rather than focusing on the coating.
PVD coating enhances tool performance by increasing the wear and oxidisation resistance of the tool and coating system. This enables either longer or faster operation, or longer and faster operation, so cutting tools maintain their strength and therefore the support for their edges and wear faces for longer.
So, if you improve your tool life, should you stop there? Maybe you should forget about the increased lifetime. Instead, focus on the increased productivity. Using the improved strength of the tool to make products more quickly, therefore having an impact on your bottom line.
If you are looking to use PVD coatings on your products, you should also look at your finish and edge prep to get the best out of PVD yourself.
Pre- and post-coating treatment can also make a difference
Measuring the life of a tool is relatively easy in a testing facility. In one example, a particular uncoated tool might achieve an average 600 punches before it needs regrinding or replacing, whereas the same tool PVD-coated might typically accomplish over a thousand. Measuring performance is more difficult and is often best conducted in the unique environment of our customers’ applications.
However, through extensive testing in Sutton Tools R&D facility, it has been established that the performance of tools can also be enhanced by treating them before and/or after coating.
Pre-treatment of tools can be critical, because PVD coating cannot fill a rough surface. Smoothing rough surfaces to remove blemishes and burrs prior to coating will typically result in a better final product.
Post-treatment of coated tools removes any surface defects created during the coating process.
This all leads to what we’ve also shown through extensive testing. Post-polishing of PVT-processed tools can benefit from an optimum form of surface preparation – not only in terms of tactile feel, but in their subsequent performance.
In summary…
PVD coating is a highly advanced technology that optimises the performance of tools for a range of applications and working harder materials. The process can be further enhanced by pre- and post-coating treatment.
Every tool and its application are different – so, if you want to improve productivity and reduce your costs, it’s important to fully understand and consider your coating options for maximising the performance of your manufacturing processes.
For more details on the CNC tooling we supply why not visit our online shop