Surface Texturing-Plasma Nitriding Duplex Treatment for Improving Tribological Performance of AISI 316 Stainless Steel

Abstract

Surface texturing-plasma nitriding duplex treatment was conducted on AISI 316 stainless steel to improve its tribological performance. Tribological behaviors of ground 316 substrates, plasma-nitrided 316 (PN-316), surface-textured 316 (ST-316), and duplex-treated 316 (DT-316) in air and under grease lubrication were investigated using a pin-on-disc rotary tribometer against counterparts of high carbon chromium bearing steel GCr15 and silicon nitride Si3N4 balls. The variations in friction coefficient, mass loss, and worn trace morphology of the tested samples were systemically investigated and analyzed. The results showed that a textured surface was formed on 316 after electrochemical processing in a 15 wt % NaCl solution. Grooves and dimples were found on the textured surface. As plasma nitriding was conducted on a 316 substrate and ST-316, continuous and uniform nitriding layers were successfully fabricated on the surfaces of the 316 substrate and ST-316. Both of the obtained nitriding layers presented thickness values of more than 30 μm. The nitriding layers were composed of iron nitrides and chromium nitride. The 316 substrate and ST-316 received improved surface hardness after plasma nitriding. When the tribological tests were carried out under dry sliding and grease lubrication conditions, the tested samples showed different tribological behaviors. As expected, the DT-316 samples revealed the most promising tribological properties, reflected by the lowest mass loss and worn morphologies. The DT-316 received the slightest damage, and its excellent tribological performance was attributed to the following aspects: firstly, the nitriding layer had high surface hardness; secondly, the surface texture was able to capture wear debris, store up grease, and then provide continuous lubrication.

Surface damage mitigation of Ti6Al4V alloy via thermal oxidation for oil and gas exploitation application: characterization of the microstructure and evaluation of the surface performance

“…However, this kind of link with insufficient bonding strength might be torn by a relative sliding of the friction pairs and result in adhesive wear. 96 In addition, the GCr15 steel was harder than the Ti6Al4V alloy, and asperities on GCr15 exerted a signicant ploughing effect on the Ti6Al4V alloy. The formed grooves/scratches were wide, deep and distinguished from the grinding scratches shown in Fig.…”

“…There was a dislocation pileup region on the near surface, which worked to induce the initiation of micro-cracks underneath the surface. [96][97][98] The cracks gradually propagated with the development of plastic deformation as the cracks extended to the surface. As a result, thin and long wear sheets were formed and spalled from the surface.…”

“…The wear sheets were ground into small size abrasive particles by the relative motion of friction pairs, and abrasive wear occurred. [96][97][98] Thereby, the wear mechanism of the Ti6Al4V alloy was a composite form of delamination and abrasive wear. Seen from Fig.…”

“…Once the crack propagation ran to a degree, aking off appeared on the worn surface. 57,[96][97][98] Si 3 N 4 possesses a higher hardness and higher chemical stability, and the TO layer was going to be worn. Compared with the Ti6Al4V alloy, a higher hardness on the surface of the TO layer could reduce the wearing damage from Si 3 N 4 , but asperities on Si 3 N 4 still played a ploughing effect on the TO layer surface and le scratches.…”

Tribological Performance of Microhole-Textured Carbide Tool Filled with CaF2

“…The surface texturing is beneficial to entrap the wear debris, supply lubricant, and enhance the load capacity with fluid lubrication [18,19,20,21,22], which may effectively reduce the friction and wear of the sliding surface. The literature has increasingly been investigating the role of the textured surface in cutting tools.…”