Emerald Group Publishing Limited
Copyright © 2004, Emerald Group Publishing Limited
New DLC coatings
New DLC coatings
Keywords: Aerospace, Components, Coatings
Diamolith from Tecvac claims high lubricity and extended life for aerospace components.
Tecvac Ltd of Cambridge, UK, has added a new diamond-like carbon coating to its comprehensive range of ultra hard coating services. Diamolith coatings are both inert and highly wear-resistant, with hardnesses of up to 4,500 HV (45 GPA), and are reported to be more than four times as hard as best chrome plate. These Diamolith coatings are also said to be highly lubricious, with a coefficient of friction as low as 0.05.
Following an exclusive UK marketing agreement with the French originator of Diamolith, the Innovative Coatings Company (ICC), Tecvac will collaborate with ICC on developing new applications of DLC in aerospace.
Tecvac director Peter Carpenter commented, “This new agreement extends our range of advanced plasma-based coating techniques. We have already developed a number of multi-layer, ultra hard combinations from our range of titanium nitride, chromium nitride and other advanced coatings, which offer new routes to radical performance improvements for titanium, steel, nickel chrome and cobalt chrome in aerospace, gas turbines, medical and high performance automotive applications. DLC offers the prospect of extending the envelope yet again”.
Diamolith coatings claim a combination of lubricity and high hardness, to radically improve the performance. They can reportedly be applied to all types of metal surfaces at low process temperatures, typically 200-300°C. This includes tool steels, stainless steels, nickel chrome steels, aluminium, titanium and molybdenum, and their alloys, carbides and beryllium copper.
The Diamolith formulation, with a mixture of diamond type and graphite type carbon structures, and a density of 1.8-2.2 g/cm3, is applied using plasma-assisted chemical vapour deposition (PACVD). It reportedly retains original surface characteristics of finished parts, even those with complex forms, re-entrant envelopes and deep hole bores, with an applied thickness of between 3 and 5 μm, depending upon the application. Diamolith has high levels of chemical resistance. It is inert in acids, alkalis, solvents, salts and water. In addition, Diamolith is said to create high integrity surfaces with an adherent composition, which is highly resistant to thermal changes.
For further details, contact: Wallwork Heat Treatment Ltd. Tel: +44 (0) 161 797 9111; Fax: +44 (0) 161 763 1861; Web site: www.wallworkht.com