The Tribological Properties of the CoCrFeNiMn High-Entropy Alloy Matrix Composites with Solid Lubrication
1
Department of Mechanical Engineering, Taiyuan Institute of Technology, Taiyuan 030008, China
2
School of Material Science and Engineering, North University of China, Taiyuan 030008, China
*
Author to whom correspondence should be addressed.
Coatings 2025, 15(9), 1098; https://doi.org/10.3390/coatings15091098
Submission received: 9 August 2025
/
Revised: 5 September 2025
/
Accepted: 15 September 2025
/
Published: 19 September 2025
(This article belongs to the Special Issue Microstructure and Corrosion Behavior of High-Entropy Coatings)
Abstract
CoCrFeNiMn HEA-based composites with Cr3C2, 15% Ag, and different mass fractions of CaF2/BaF2 eutectic fluoride were fabricated by spark plasma sintering. The tribological properties and wear mechanism of the composites were investigated from RT to 800 °C. The friction coefficients of CoCrFeNiMn-Cr3C2-Ag-CaF2/BaF2 composites decrease from RT to 800 °C except for 400 °C. At 800 °C, with the increasing mass fraction of the eutectic fluoride, the friction coefficient of the composite decreases from 0.53 to 0.25. The wear rates of the composite with 15% CaF2/BaF2 eutectic fluoride decrease significantly at high temperatures. The CoCrFeNiMn-Cr3C2-Ag-15%CaF2/BaF2 composite exhibits the lowest wear rates at 400 °C, 600 °C, and 800 °C, which are 4.47 × 10−6 mm3/N·m, 5.15 × 10−6 mm3/N·m, and 2.42 × 10−6 mm3/N·m, respectively. At low temperatures, the tribological mechanisms of the composites are micro-plowing and micro-cutting, and Ag is formed as a lubricating film to reduce the friction coefficient. At high temperature, fluorides form a transfer film on the wear scar surface, providing a lubricating effect. Also, the oxide layers and chromate are formed on the worn surfaces of the composites, which are beneficial for improving the wear resistance. Based on the mechanical properties and tribological behavior, the CoCrFeNiMn-Cr3C2-Ag-15%CaF2/BaF2 composite demonstrates the best comprehensive properties.
1. Introduction
The self-lubricating composite which is composed of the alloy matrix, reinforced phase and solid lubrication is applied for a wide temperature range especially at high temperatures [1,2,3]. The National Aeronautics and Space Administration (NASA) has successfully developed a series of high-temperature self-lubricating composite coatings and materials containing eutectic fluorides, which exhibit excellent tribological properties [4,5,6]. Among them, the PS304 [4] and PM304 [5,6] material demonstrates good tribological properties at a wide temperature range from room temperature to 650 °C and has been widely applied. However, its wear resistance decreases at 800 °C due to the decline in the mechanical properties of the matrix material. Also many researchers develop the Ni-based alloy matrix self-lubricating composites which possess excellent tribological properties, such as Ni3Al [7], NiAl [8,9], NiCr [10], Ni3Si [11] matrix. However, achieving composites with both excellent mechanical and tribological properties remains a major challenge for metal-based self-lubricating composites.
The proposal of the high-entropy alloy concept has created a tremendous, worldwide impetus for alloy design [12]. The high-entropy alloy (HEA) is composed of multiple alloying elements which is in equal or near-equal atomic ratios. The high configuration entropy facilitates the formation of a simple solid solution. The unique crystal structure of high-entropy alloys determines their possession of many excellent properties [13,14,15,16,17,18,19,20,21], such as high strength, high toughness, as well as outstanding wear resistance, oxidation resistance, corrosion resistance, and thermal stability. The distinctive microstructure and superior performance of high-entropy alloys endow them with tremendous development potential in both theoretical research and industrial applications [22,23]. They are expected to be utilized in wear-resistant materials, such as AlCoCrFeNiTi0.2 [15], CoCrFeNi [20] high-entropy alloys. Among the various high-entropy alloys, the CoCrFeNiMn high-entropy alloy possesses a simple structure with a single FCC phase, exhibiting high strength and toughness [17]. The yield strength of the CoCrFeNiMn high-entropy alloy reaches 500 MPa, and its fracture toughness is as high as 200 MPa·m−1/2. Therefore, CoCrFeNiMn high-entropy alloy is a good candidate for self-lubricating composite matrix.
Based on the optimized CoCrFeNiMn-10%Cr3C2-15%Ag composite from the previous study [24,25,26], we introduce the high-temperature solid lubricant eutectic fluoride CaF2/BaF2. As a high-temperature solid lubricant, fluorides possess high chemical and thermal stability, remaining highly stable even under extreme oxidative and reductive atmospheres at elevated temperatures. After undergoing a ductile-to-brittle transition, fluorides exhibit low shear strength, thereby providing excellent lubrication properties. The CoCrFeNiMn-10%Cr3C2-15%Ag-CaF2/BaF2 composites with different mass fraction eutectic fluoride CaF2/BaF2 were prepared by spark plasma sintering. The friction and wear properties were investigated at a wide temperature range from room temperatures to 800 °C, and the tribological mechanisms of the composites were discussed.
2. Materials and Methods
The CoCrFeNiMn-Cr3C2-Ag-CaF2/BaF2 composite material was prepared by spark plasma sintering (SPS). High-purity (99.9%) pre-alloyed CoCrFeNiMn powder, Cr3C2 powder, Ag powder, and eutectic fluoride CaF2/BaF2 powder were mixed, with the mass fraction of Cr3C2 powder at 10%, Ag at 15%, and the eutectic fluoride at 5% and 15%, respectively. The mass friction of each component in composites is shown in Table 1. The average particle sizes of the CoCrFeNiMn powder, Cr3C2 powder, Ag powder, and eutectic CaF2/BaF2 powder were 53 μm, 25 μm, 35 μm, and 35 μm, respectively.
The material of the milling jar is ZrO2, and the material of the ball is also ZrO2. The mixed powders were loaded into the ball milling jar with a ball-to-powder ratio of 1:1, a milling speed of 150 rad/min, and a milling time of 10 h. Planetary ball mills was operated in an atmospheric environment. The uniformly mixed powder was then placed into a graphite die and sintered under vacuum in a a SPS-20 T-10 furnace (Shanghai Chen Hua Technology Co., Shanghai, China). The sintering pressure was set at 30 MPa, with a heating rate of 50 °C/min. When the temperature reached 950 °C, it was held for 20 min, followed by furnace cooling. Finally, the successfully sintered samples were retrieved.
The friction experiments of the composite were conducted on a high-temperature tribometer (HT-1000, Zhongke Kaihua Technology Co., Ltd., Lanzhou, China) at room temperature, 200 °C, 400 °C, 600 °C and 800 °C. A ball-on-disk contact configuration was employed, with the sample dimensions being Φ 25 mm × 5 mm. The relative motion was purely rotational. The sample was underwent rotational motion, while the Si3N4 ball remained stationary. The surface of the sample disk was polished with 1000# SiC sandpaper, and the counter ball was a Si3N4 ball with a diameter of Φ 6 mm. The applied load was 5 N, the sliding speed was 0.28 m/s, and the friction test duration was 30 min. The coefficient of friction at each test temperature was the average of three measurements under the same experimental conditions. After the friction tests, the wear scar morphology was characterized using scanning electron microscopy (SEM). The elemental distribution inside and outside the wear scar was analyzed using energy-dispersive X-ray spectroscopy (EDS). The oxides on the wear scar surface were characterized using Raman spectroscopy (Renishaw in Via, London, UK) and X-ray photoelectron spectroscopy (XPS, ESCALAB 250Xi, Thermo Fisher Scientific Inc., Waltham, MA, USA). The wear rates of the alloy and composite were measured using a two-dimensional surface profilometer (D-100, KLA Co., Milpitas, CA, USA). The wear volume is the area of wear scar depth profile multiplied by the wear scar perimeter. The experiment results were the average of ten measurements. All instruments are calibrated before the experiment.
3. Results and Discussion
As shown in Figure 1, the friction coefficient and the average friction coefficient comparison curves of the CoCrFeNiMn-Cr3C2-Ag-CaF2/BaF2 composites are presented. From Figure 1a,b, it can be observed that the friction coefficients of the CoCrFeNiMn-Cr3C2-Ag-CaF2/BaF2 composite remain relatively stable at different temperatures. At room temperature, the friction coefficient of CoCrFeNiMn-Cr3C2-Ag composite is 0.51. The friction coefficient of CoCrFeNiMn-Cr3C2-Ag-CaF2/BaF2 composite with 5% and 15% eutectic fluoride is 0.47 and 0.56, respectively. The friction coefficient of the different composites changes slightly. As the temperature rises to 200 °C, the friction coefficient of the composites continuously decreases with the increase in the mass fraction of eutectic fluoride CaF2/BaF2. The friction coefficient of CoCrFeNiMn-Cr3C2-Ag-CaF2/BaF2 composite with 0%, 5% and 15% eutectic fluoride is 0.41, 0.36 and 0.29, respectively. At 400 °C, the friction coefficient of the composites with different mass fractions of eutectic fluoride is 0.45, which do not exhibit significant changes, but their friction coefficients are higher than the CoCrFeNiMn-Cr3C2-Ag composite. However, with the temperature increasing to 600 and 800 °C, the friction coefficients of the composite decrease obviously as the mass fraction of eutectic fluoride CaF2/BaF2 increases. At 600 °C, the friction coefficient of CoCrFeNiMn-Cr3C2-Ag composite is 0.49. With the addition of 5% and 15% eutectic fluoride, the friction coefficient of composites decrease to 0.38 and 0.34, respectively. At 800 °C, with the increasing mass fraction of the eutectic fluoride, the friction coefficient of the composite decrease from 0.53 to 0.25.
Figure 2 shows the wear rate of CoCrFeNiMn-Cr3C2-Ag-CaF2/BaF2 composites at different temperatures. At room temperature and 200 °C, the wear rate of the composites gradually increases with the rise in the mass fraction of eutectic fluorides. However, at 400 °C, 600 °C, and 800 °C, the wear rate of the composite with 5% eutectic fluorides is higher than that of both the CoCrFeNiMn-Cr3C2-Ag composite without eutectic fluorides and the composite with 15% eutectic fluorides. The CoCrFeNiMn-Cr3C2-Ag-15%CaF2/BaF2 composite exhibits the lowest wear rates at 400 °C, 600 °C, and 800 °C, which are 4.47 × 10−6 mm3/N·m, 5.15 × 10−6 mm3/N·m, and 2.42 × 10−6 mm3/N·m, respectively.
Figure 3 shows the SEM images of wear scar morphologies of the CoCrFeNiMn-Cr3C2-Ag-5%CaF2/BaF2 composite at different temperatures. At room temperature and 200 °C, the detachment of fluoride-rich zones, micro-pits, and cracks indicate that the primary wear mechanisms are micro-fracturing and spalling [27]. At 400 °C, a large amount of wear debris and a small amount of spalling layers are observed on the wear scar surface, suggesting that the dominant wear mechanisms are micro-plowing and spalling. At 600 °C, the wear scar surface is relatively smooth and flat, with the formation of an oxide layer, along with shallow plowing grooves, indicating that the main wear mechanism is micro-plowing. At 800 °C, the wear scar surface is comparatively smooth, primarily due to the formation of an oxide glaze layer. A small amount of wear debris and plowing grooves can be observed on the surface, demonstrating that the primary wear mechanism is micro-plowing.
Table 2 presents the elemental distribution inside and outside the wear scars of the CoCrFeNiMn-Cr3C2-Ag-5%CaF2/BaF2 composite at different temperatures. The Ag content inside the wear scars is higher than the outside. Ag has low shear strength and tends to coat the surface of wear scars during friction, which paly a lubricating effect. This consequently endows the composite with excellent anti-friction and wear resistance. The oxygen content inside the wear scars is consistently higher than that outside, indicating that tribo-oxidation occurs during friction at all tested temperatures [28]. Moreover, as the temperature increases, the oxygen content inside the wear scars gradually rises, suggesting that the wear scar surface undergoes continuous oxidation with increasing temperature. Additionally, at 800 °C, higher concentrations of Ca and Ba elements are detected inside the wear scar, indicating that fluorides form a transfer film on the wear scar surface, providing a lubricating effect.
Figure 4 shows the wear scar morphologies of the CoCrFeNiMn-Cr3C2-Ag-15%CaF2/BaF2 composite at different temperatures. At room temperature, large-scale spalling of the fluoride-rich zone can be observed, indicating that the primary wear mechanism is spalling. At 200 °C, 400 °C, and 600 °C, grooves and wear debris are visible on the wear scar surface, suggesting that the dominant wear mechanisms are micro-plowing and micro-cutting. At 800 °C, oxide adhesion is observed on the wear scar surface, indicating that oxidative wear is the main wear mechanism. The formation of an oxide film at high temperatures serves a lubricating function and also protects the composite from wear.
Table 3 presents the distribution of elements inside and outside the wear scars of the CoCrFeNiMn-Cr3C2-Ag-15%CaF2/BaF2 composite at different temperatures. The Ag is exposed on the wear scar to lubricate. Oxidation occurs within the wear scars at all temperatures, but the oxygen content is highest at 800 °C, reflecting the formation of an oxidative glaze layer under high-temperature conditions. Additionally, at 800 °C, the concentrations of Ca and Ba elements on the wear scar surface are significantly higher than at other temperatures, indicating an increase in eutectic fluorides and their oxides on the wear scar surface. Compared the chemical composition in Table 2, the Ba, Ca and F content in CoCrFeNiMn-Cr3C2-Ag-15%CaF2/BaF2 composites is higher than the CoCrFeNiMn-Cr3C2-Ag-5%CaF2/BaF2 composites. The CaF2/BaF2 eutectic fluoride play a key role of lubrication and wear-resistance at mid-to-high temperatures. The BaF2/CaF2 eutectic fluoride undergo a ductile-to-brittle transition within this temperature range and become coated onto the worn surface during friction. The BaF2/CaF2 eutectic fluoride coated on the worn surface isolates the composite material from direct contact with the counter ball, thereby providing a certain degree of friction reduction and wear resistance. Therefore, the friction coefficient and wear resistance of composites with 15%CaF2/BaF2 is superior to the composites with 5%CaF2/BaF2.
As shown in Figure 5, the XRD spectra of the CoCrFeNiMn-Cr3C2-Ag-15%CaF2/BaF2 composite material within the wear tracks at room temperature and 800 °C are presented. At room temperature, the FCC phase, Ag, and eutectic fluorides are detected in the wear track, with no oxidation occurring during the friction process, demonstrating its excellent lubricity under low-temperature conditions. In contrast, at 800 °C, CaO, FeO, MnO2, NiO, CaF2, BaCO3, and Ag2CrO4 are detected in the wear track. Among these, BaCO3 is formed by the reaction of BaF2 with CO2 in the air, which is detrimental to lubrication. Ag2CrO4 is generated by the reaction of BaF2 with Cr from the high-entropy alloy and CO2 in the air, contributing to the improvement of the tribological properties of the composite material. Additionally, some oxides are produced by the reaction of the high-entropy alloy with oxygen in the air, providing a certain protective effect against wear in the composite material.
To further demonstrate the formation of oxides on the worn surface under high-temperature conditions, Figure 6 presents the XPS spectra of the CoCrFeNiMn-Cr3C2-Ag-15%CaF2/BaF2 composite after wear testing at 800 °C. Specifically, the Co2p peaks at 783.5 eV and 795.6 eV are attributed to Co in Co3O4, the Cr2p peaks at 577 eV and 586.87 eV correspond to Cr3+ in Cr2O3, and the Fe2p peaks at 710.8 eV and 723.9 eV are assigned to Fe in Fe3O4. The Mn2p peaks at 642.8 eV and 647.3 eV are ascribed to Mn4+ in MnO2, while those at 640.9 eV and 653.4 eV are attributed to Mn in Mn3O4. The Ni2p peaks at 855.9 eV and 873.6 eV are identified as Ni2+ in NiO. For the Ag3d peaks, those at 367.8 eV and 373.8 eV are assigned to Ag in Ag2CrO4, whereas the peaks at 369.2 eV and 375.2 eV correspond to Ag+ in Ag2O. The Ba3d peaks at 780.9 eV and 796.23 eV are attributed to Ba2+ in BaCO3, while those at 779.9 eV and 795.23 eV are assigned to Ba in BaF2. The Ca2p peaks at 351.1 eV and 347.4 eV are identified as Ca2+ in CaCO3, those at 350.3 eV and 346.7 eV correspond to Ca2+ in CaO, and the peak at 347.8 eV is ascribed to Ca2+ in CaF2. Finally, the F1s peaks at 684.0 eV and 684.8 eV are assigned to F- in BaF2 and CaF2, respectively.
At high temperatures, a glaze layer is formed on the surface of the composite material. This friction glaze layer is primarily composed of Ag, BaF2, CaF2, and various metal oxides, which improve the resistance of the composites. Also, the BaF2/CaF2 eutectic fluorides form a transfer film on the wear scar surface, providing a lubricating effect.
4. Conclusions
CoCrFeNiMn-Cr3C2-Ag-CaF2/BaF2 self-lubricating composites with different mass fractions of CaF2/BaF2 eutectic fluoride were prepared using SPS technology. Their tribological performance from room temperature to 800 °C was examined. The friction and wear mechanisms at different temperatures were analyzed. After adding CaF2/BaF2 eutectic fluoride, the friction coefficient of the CoCrFeNiMn-Cr3C2-Ag-CaF2/BaF2 composites decreases at all tested temperatures (except 400 °C). Moreover, the composite with 15% CaF2/BaF2 exhibits a significant reduction in wear rate under high-temperature conditions (400 °C to 800 °C). At low temperatures, the wear rate of the CoCrFeNiMn-Cr3C2-Ag-CaF2/BaF2 composites increases due to reduced strength. However, at high temperatures, fluorides form a transfer film on the wear scar surface, providing a lubricating effect. Also, an oxide glaze layer and chromates form on the composite surface. The oxide glaze layer protects against wear, while chromates, particularly BaCrO4, act as lubricants, leading to a lower wear rate. Considering the overall performance, the CoCrFeNiMn-Cr3C2-Ag-15%CaF2/BaF2 composite demonstrates the best properties especially at high temperatures.
Author Contributions
Methodology, J.L.; Investigation, X.R. and G.Z.; Writing—original draft, Z.G. All authors have read and agreed to the published version of the manuscript.
Funding
This work was supported by research funding from the Talent Introduction Program of Taiyuan Institute of Technology (2022KJ107).
Data Availability Statement
The original contributions presented in this study are included in the article. Further inquiries can be directed to the corresponding author.
Conflicts of Interest
The authors declare no conflicts of interest.
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Figure 1.
Typical friction coefficient curves of CoCrFeNiMn-Cr3C2-Ag-CaF2/BaF2 composites at different temperatures: (a) CoCrFeNiMn-Cr3C2-Ag-5%CaF2/BaF2, (b) CoCrFeNiMn-Cr3C2-Ag-15%CaF2/BaF2, and (c) average friction coefficient comparison curve of the composites.
Figure 1.
Typical friction coefficient curves of CoCrFeNiMn-Cr3C2-Ag-CaF2/BaF2 composites at different temperatures: (a) CoCrFeNiMn-Cr3C2-Ag-5%CaF2/BaF2, (b) CoCrFeNiMn-Cr3C2-Ag-15%CaF2/BaF2, and (c) average friction coefficient comparison curve of the composites.
Figure 2.
Wear rate of CoCrFeNiMn-Cr3C2-Ag-CaF2/BaF2 composites at different temperatures.
Figure 3.
SEM images of worn surfaces of CoCrFeNiMn-Cr3C2-Ag-5%CaF2/BaF2 composites at RT (a,b), 200 °C (c,d), 400 °C (e,f), 600 °C (g,h) and 800 °C (i,j).
Figure 3.
SEM images of worn surfaces of CoCrFeNiMn-Cr3C2-Ag-5%CaF2/BaF2 composites at RT (a,b), 200 °C (c,d), 400 °C (e,f), 600 °C (g,h) and 800 °C (i,j).
Figure 4.
SEM image of worn surfaces of CoCrFeNiMn-Cr3C2-Ag-15%CaF2/BaF2 composites at RT (a,b), 200 °C (c,d), 400 °C (e,f), 600 °C (g,h) and 800 °C (i,j).
Figure 4.
SEM image of worn surfaces of CoCrFeNiMn-Cr3C2-Ag-15%CaF2/BaF2 composites at RT (a,b), 200 °C (c,d), 400 °C (e,f), 600 °C (g,h) and 800 °C (i,j).
Figure 5.
XRD spectra of worn surfaces of CoCrFeNiMn-Cr3C2-Ag-15%CaF2/BaF2 at RT (a) and 800 °C (b).
Figure 5.
XRD spectra of worn surfaces of CoCrFeNiMn-Cr3C2-Ag-15%CaF2/BaF2 at RT (a) and 800 °C (b).
Figure 6.
XPS spectra of worn surface of CoCrFeNiMn-Cr3C2-Ag-15%CaF2/BaF2 composites at 800 °C.
Table 1.
The mass friction of each component.
| Sample | CoCrFeNiMn | Cr3C2 | Ag | BaF2/CaF2 |
|---|---|---|---|---|
| HEA-Ag | 75 | 10 | 15 | 0 |
| HEA-Ag-5%CaF2/BaF2 | 70 | 10 | 15 | 5 |
| HEA-Ag-15%CaF2/BaF2 | 60 | 10 | 15 | 15 |
Table 2.
Chemical composition of worn surfaces of CoCrFeNiMn-Cr3C2-Ag-5%CaF2/BaF2 at different temperatures.
Table 2.
Chemical composition of worn surfaces of CoCrFeNiMn-Cr3C2-Ag-5%CaF2/BaF2 at different temperatures.
| Temperature (°C) | Areas | Composition (at%) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| C | O | F | Ca | Cr | Mn | Fe | Co | Ni | Ag | Ba | ||
| RT | Inside | 22.3 | 26.4 | 3.5 | 0.4 | 11.8 | 8.9 | 8.5 | 8.3 | 8.0 | 1.7 | 0.3 |
| Outside | 26.5 | 3.9 | 8.1 | 1.3 | 21.6 | 9.8 | 9.5 | 9.0 | 8.3 | 1.5 | 0.5 | |
| 200 | Inside | 34.3 | 20.7 | 3.9 | 0.4 | 11.9 | 6.6 | 6.3 | 5.7 | 5.9 | 3.9 | 0.3 |
| Outside | 35.7 | 9.1 | 3.5 | 0.7 | 18.6 | 8.6 | 7.8 | 7.6 | 6.8 | 1.2 | 0.4 | |
| 400 | Inside | 16.1 | 34.5 | 4.3 | 0.5 | 13.9 | 7.1 | 6.7 | 6.6 | 6.8 | 3.2 | 0.4 |
| Outside | 20.2 | 10.7 | 9.3 | 1.2 | 23.0 | 8.9 | 8.9 | 8.4 | 7.7 | 1.1 | 0.5 | |
| 600 | Inside | 9.1 | 44.8 | 1.1 | 0.8 | 11.2 | 7.7 | 7.6 | 7.0 | 6.7 | 3.5 | 0.5 |
| Outside | 16.4 | 26.4 | 4.4 | 1.1 | 17.3 | 9.3 | 8.4 | 7.7 | 7.5 | 1.1 | 0.5 | |
| 800 | Inside | 6.1 | 52.4 | 4.7 | 5.6 | 7.4 | 11.5 | 2.2 | 1.7 | 0.8 | 1.0 | 6.6 |
| outside | 12.3 | 46.9 | 4.4 | 4.4 | 7.5 | 16.1 | 1.8 | 1.2 | 0.7 | 0.1 | 4.5 | |
Table 3.
Chemical compositions of worn surfaces of CoCrFeNiMn-Cr3C2-Ag-15%CaF2/BaF2 at different temperatures.
Table 3.
Chemical compositions of worn surfaces of CoCrFeNiMn-Cr3C2-Ag-15%CaF2/BaF2 at different temperatures.
| Temperature (°C) | Areas | Composition (at%) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| C | O | F | Ca | Cr | Mn | Fe | Co | Ni | Ag | Ba | ||
| RT | Inside | 15.7 | 48.1 | 9.7 | 1.5 | 7.7 | 3.6 | 3.3 | 3.4 | 3.3 | 2.6 | 1.1 |
| Outside | 40.6 | 5.0 | 11.6 | 2.9 | 15.4 | 5.9 | 5.8 | 5.5 | 5.1 | 1.2 | 1.2 | |
| 200 | Inside | 33.8 | 39.9 | 4.3 | 1.0 | 5.6 | 3.3 | 2.5 | 2.4 | 2.5 | 3.8 | 0.8 |
| Outside | 34.5 | 15.3 | 8.4 | 1.9 | 14.2 | 6.1 | 6.2 | 5.8 | 5.5 | 0.9 | 1.3 | |
| 400 | Inside | 31.0 | 36.6 | 4.5 | 0.8 | 6.7 | 4.7 | 4.2 | 4.3 | 4.2 | 2.1 | 1.0 |
| Outside | 26.1 | 17.4 | 6.0 | 2.6 | 19.2 | 7.2 | 6.9 | 6.3 | 5.8 | 1.3 | 1.2 | |
| 600 | Inside | 28.0 | 38.5 | 1.9 | 1.5 | 8.3 | 4.9 | 4.6 | 4.4 | 4.3 | 2.4 | 1.3 |
| Outside | 24.2 | 30.1 | 4.0 | 2.3 | 13.3 | 6.8 | 6.1 | 5.5 | 5.3 | 1.2 | 1.3 | |
| 800 | Inside | 24.1 | 51.3 | 3.0 | 8.7 | 0.5 | 0.3 | 0.3 | 0.3 | 0.3 | 0.1 | 11.4 |
| Outside | 21.9 | 51.9 | 3.1 | 11.5 | 0.6 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | 10.8 | |
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MDPI and ACS Style
Guo, Z.; Ren, X.; Li, J.; Zhang, G. The Tribological Properties of the CoCrFeNiMn High-Entropy Alloy Matrix Composites with Solid Lubrication. Coatings 2025, 15, 1098. https://doi.org/10.3390/coatings15091098
AMA Style
Guo Z, Ren X, Li J, Zhang G. The Tribological Properties of the CoCrFeNiMn High-Entropy Alloy Matrix Composites with Solid Lubrication. Coatings. 2025; 15(9):1098. https://doi.org/10.3390/coatings15091098
Chicago/Turabian StyleGuo, Zhiming, Xiaoyan Ren, Jingdan Li, and Guowei Zhang. 2025. "The Tribological Properties of the CoCrFeNiMn High-Entropy Alloy Matrix Composites with Solid Lubrication" Coatings 15, no. 9: 1098. https://doi.org/10.3390/coatings15091098
APA StyleGuo, Z., Ren, X., Li, J., & Zhang, G. (2025). The Tribological Properties of the CoCrFeNiMn High-Entropy Alloy Matrix Composites with Solid Lubrication. Coatings, 15(9), 1098. https://doi.org/10.3390/coatings15091098
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