Diamonds are the hardest naturally occurring material known to man. They’re used on drill bits and abrasive cutting blades to carry out all sorts of tough tooling jobs. Other materials, even tough carbides, find that kind of work next to impossible to emulate. Unsurprisingly, and this development is set to revolutionize the industry, diamond-like carbon coatings are heading towards the thin-film coatings sector, and those films are an essential part of the die manufacturing industry.

Adding a Diamond-Like Advantage

Make no mistakes, metals are extraordinarily tough. They’re hard enough to form the skeletons of massive buildings, after all. Still, a crystal-type tool coating does have several unique benefits to offer. There’s that nigh-on unbreakable microcrystalline structure to add to the die and punch manufacturing industry. Then there are the sticking and coarseness issues that hamper those tough-as-nails metals. Carbon coatings, morphed into their diamond-like forms, don’t suffer from this particular issue.

Supported By Slippery Finishes

Advanced lubricants and heat-treated finishes aid hardened metal punches, but there’s another problem. Simply this, manufacturers are demanding stronger parts. In the automobile industry alone, denser carbon-strengthened alloys require equally hard tools, which can cut or impact-form sharply defined edges. Durable metal punches do the job, but they create galling and sticking issues. In higher density aluminium alloys, for example, localized melting problems take their toll. To counteract the galling, special Titanium Carbon Nitride (TiCN) coatings provide some static friction resistance, all while presenting a thermally toughened shield, but that finish is no longer enough, not in this material-dense age.

What Is A Diamond-Like Coating?

Great strides are taking place in this area. There are carbon fibres, which add incredible strength, yet the products coated in these space-age materials stay light and portable. As a tooltip finish, diamond-like carbon (DLC) coatings serve several purposes. They’re very hard, of course, plus they exhibit a slippery surface, which is a little like a ceramic covering. Applied by Physical Vapour Deposition technology, the thin film provides a low coefficient of friction, yet it’s durable and gifted with a degree of fatigue and fracture resistance that’s hard to find in any other coating offering.

Simply put, contemporary punch and die technology is built on a many-layered framework. There’s the base metal, which is super-hard and dense. It’s heat-treated and lubricated. Next on the layering chart, special thin films, applied by PVD or PACVD technology, exist to prevent impact galling and localized melting effects. In the past, titanium and ceramic-based coatings did the job. Today, with alloys delivering more impact resisting strength than ever before, engineers are exploring DLC tech and discovering new ways to deliver the abrasion-less strokes which prevent localized melting.