Characteristics of DLC/oxynitriding duplex-treated V8 tool steel by DC-pulsed PECVD

Abstract

In this paper, DLC films are produced by DC-pulsed plasma enhanced CVD after oxynitridetreating of Vanadis 8 tool steel. The experimental parameters include various Ar gas flows (1, 1.5, 2 and 2.5 sccm) with asymmetric bipolar pulsed voltages, the gas flow of CH 4 and a deposition time of 90 min, respectively. The experimental results showed that optimal properties occurred at an appropriate argon gas flow of 1.5 sccm. The wear tests showed the lowest wear loss volume when loads of 2 and 5 N were 3.81 × 10 −3 and 4.01 × 10 −3 mm 3 , respectively. Meanwhile, the hardness of the DLC film was 17.78 GPa and the elastic modulus was 191.63 GPa, respectively. Moreover, the water contact angle was 78.11°, which indicated that the DLC films could make Vanadis 8 tool steel more hydrophobic.

Optimization of DLC films on oxynitriding-treated Vanadis 10 tool steel through the various duty cycles of DC-pulsed plasma-enhanced CVD

“…It has been found that using intermediate layers between the DLC film and the substrate can increase the adhesion strength of the film [13,14]. As studied previously, the oxynitriding layer improves the corrosion properties and the adhesive strength as an interlayer [3][4][5]. Therefore, this research utilized DC-pulsed plasmaenhanced CVD and DLC/oxynitriding duplex treatments to study the characteristics of DLC films and improve the coating properties of V10 tool steel.…”

“…Oxynitriding is the process that includes gas nitriding and post-oxidizing treatments, which use steam at the end of the nitriding step [3]. Generally speaking, the oxynitriding process can form several kinds of nitride (Fe 2 N, Fe 3 N, and Fe 4 N) and oxides (Fe 2 O 3 and Fe 3 O 4 ).…”

“…Particularly, the Fe 3 O 4 layer of oxidation treatment can effectively protect and improve steels' erosion and corrosion resistance. Our previous studies showed that the oxynitriding layer could form the passive oxidative film, which improved the adhesive strength as an intermedi-ate layer during the duplex coating treatments [3][4][5].…”

The properties of lubricated friction pairs with diamond-like carbon coatings

“…Today, they are used in almost every branch of industry, from electronics, mechanical equipment, microelectromechanical circuits to optics [1] and medicine [2]. Diamond-like coatings have very good physical, chemical [1] and tribological properties, in particular: low friction coefficient, high resistance to wear and high hardness [1,[3][4][5]. Another advantage of diamond-like coatings is that they can be applied to almost any engineering material: metals, ceramics and polymers.…”

“…It is a mixture of carbon atoms with sp3 and sp2 bonds, which are characteristic for diamond and graphite respectively. The ratio of sp2/sp3 carbon atoms is one of the most important factors influencing the properties of diamond-like coatings [4]. The structural properties of all DLC coatings are similar, but their tribological and mechanical properties differ greatly, and this is influenced by the technique and parameters of the deposition process [5].…”