Effect of the slide-to-roll ratio and the contact kinematics on the elastohydrodynamic friction in diamond-like-carbon contacts with different wetting behaviours

Polajnar, Marko (avtor), Kalin, Mitjan (avtor)

In this paper, we show how the slide-to-roll ratio (SRR), the contact kinematics and the surface energy all have important effects on the elastohydrodynamic friction. As reported previously, diamond-like-carbon (DLC) contacts of the type DLC/DLC provide the lowest coefficient of friction, in particular those DLC materials with the lowest surface energies (three different DLC coatings were used in this study). A friction reduction of up to 48 %, compared to a steel/steel contact, was obtained. A surprising new finding from this investigation is that the friction in DLC contacts is significantly reduced for high SRRs, i.e. a difference of up to 27 % was measured in the DLC/DLC contacts when the SRR increased from 0.5 (rolling prevails) to 1.8 (sliding prevails). However, even more surprising is the effect of the SRR on the friction in mixed steel/DLC contacts, which is related to the contact design and its kinematics. We found that if the DLC is coated on the slower surface, a high SRR will not reduce the friction to any significant extent, typically about 5 %, and at most 13 %, compared to steel/steel contacts. However, a significant friction reduction is observed when applying a low-surface-energy DLC coating to the faster surface-on average about 20 % and as high as 33 %. In this case (a high SRR and DLC on the faster surface), mixed steel/DLC surfaces can experience a very similar friction as that seen for DLC/DLC contacts. Qualitatively, the same behaviour was found for both positive and negative SRR values.

• Jezik: Angleški jezik
• Ključne besede: EHD lubrication, DLC, surface energy, wetting, slide-to-roll ratio
• Vrsta gradiva: Članek v reviji
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: FS - Fakulteta za strojništvo
• Status publikacije: Objavljeno
• Različica publikacije: Recenzirani rokopis
• Leto izida: 2015
• Št. strani: Str. 1-10
• Številčenje: Vol. 60, iss. 1
• PID: 20.500.12556/RUL-106740
• UDK: 539.92(045)
• ISSN pri članku: 1023-8883
• DOI: 10.1007/s11249-015-0593-3
• COBISS.SI-ID: 14197019
• Datum objave v RUL: 14.03.2019

Gradivo je del revije

• Naslov: Tribology letters
• Skrajšan naslov: Tribol. lett.
• Založnik: Baltzer, Baltzer Science Publishers
• ISSN: 1023-8883
• COBISS.SI-ID: 2806555

Sekundarni jezik

• Jezik: Slovenski jezik
• Ključne besede: tribologija, mazanje, DLC prevleke

Projekti

• Financer: ARRS - Agencija za raziskovalno dejavnost Republike Slovenije
• Številka projekta: P2-0231
• Naslov: Tribologija