Low friction coefficient nanocomposite CrAlSiN/gradient-CrAlSiCN coatings for high speed/dry machining applications

2021 ◽  
pp. 1-24
Author(s):  
Puneet Chandran ◽  
Krishna Valleti ◽  
Venu Gopal Anne
Keyword(s):  
Friction Coefficient ◽  
Adhesion Strength ◽  
Tool Life ◽  
Tribological Properties ◽  
High Speed ◽  
Nanocomposite Coating ◽  
Dry Machining ◽  
Wear Properties ◽  
Low Friction ◽  
Dlc Coating

Abstract Providing advanced coating solutions for high speed dry machining applications is gaining importance by the day especially with the increasing employment of difficult-to-machine materials in niche areas. Taking into account the recent demands in developing such coatings, in the present study, a novel low friction coefficient nanocomposite coating: CrAlSiN/G-CrAlSiCN (G: Gradient) was developed which can be used in high speed or dry machining applications. Initially, CrAlSiN nanocomposite coating and carbon incorporated CrAlSiN coating were deposited separately using the cylindrical cathodic arc PVD technique. The as deposited films were comprehensively analyzed to determine their adhesion strength, phase composition, sliding wear properties (friction coefficient), hardness and tool life. Preliminary observations revealed that the films did not show evidence of diamond-like carbon (DLC) formation (from Raman analysis). Further, an increase in the carbon content led to a steep decrease in the adhesion strength. This result persuaded a study on developing a novel coating with gradient carbon architecture which would retain the properties of a nanocomposite whilst supporting the nanocomposite under-layer by reducing the coefficient of friction. In comparison to the CrAlSiN nanocomposite coating and a standard DLC coating, the novel gradient carbon coating showed superior tribological properties along with a better tool life. This study marks the first such attempt at studying the influence of carbon incorporation to the CrAlSiN nanocomposite coating on improving the overall mechanical and tribological properties of the coating architecture (CrAlSiN/G-CrAlSiCN) for dry machining applications.

Research on Tribological Properties of Cast Iron at High-Speed Dry Sliding Condition

2014 ◽  
Vol 936 ◽  
pp. 2063-2067
Author(s):  
Chen Yue ◽  
Shang Guan Bao ◽  
Ying Yu Huang
Keyword(s):  
Cast Iron ◽  
Friction Coefficient ◽  
Wear Rate ◽  
Abrasive Wear ◽  
Tribological Properties ◽  
High Speed ◽  
Friction Material ◽  
Dry Sliding ◽  
Oxidative Wear ◽  
Wear Properties

The friction and wear properties of cast iron with different graphite morphologies and matrix microstructure were investigated at high speed dry sliding against GCr15 steel on the MMS-1G high-speed tribometer apparatus. The various wear micro-mechanisms and tribo-metallographic phases were studied by using scanning electron microscopy. The results show that as friction material, vermicular iron exhibits excellent comprehensive tribological properties. The friction coefficient of cast iron sliding against GCr15 decreases while the wear rate increases with the increase of sliding speed, friction coefficient and wear rate decline with the increase of pearlite content. Under the experimental condition, the main wear mechanisms of flake iron are abrasive wear, of vermicular iron are abrasive wear and oxidative wear and of nodular iron are oxidative wear, abrasive wear and fatigue spalling.

scholarly journals Fabrication and Tribological Properties of Copper Matrix Solid Self-Lubricant Composites Reinforced with Ni/NbSe2 Composites

Materials ◽  
2019 ◽  
Vol 12 (11) ◽  
pp. 1854
Author(s):  
Fei-xia Zhang ◽  
Yan-qiu Chu ◽  
Chang-sheng Li
Keyword(s):  
Powder Metallurgy ◽  
Friction Coefficient ◽  
Wear Rate ◽  
Tribological Properties ◽  
Friction And Wear ◽  
Copper Matrix ◽  
Wear Properties ◽  
Disk Friction ◽  
Friction Reducing ◽  
Properties Of Composites

This paper presents a facile and effective method for preparing Ni/NbSe2 composites in order to improve the wettability of NbSe2 and copper matrix, which is helpful in enhancing the friction-reducing and anti-wear properties of copper-based composites. The powder metallurgy (P/M) technique was used to fabricate copper-based composites with different weight fractions of Ni/NbSe2, and tribological properties of composites were evaluated by using a ball-on-disk friction-and-wear tester. Results indicated that tribological properties of copper-based composites were improved by the addition of Ni/NbSe2. In particular, copper-based composites containing 15 wt.% Ni/NbSe2 showed the lowest friction coefficient (0.16) and wear rate (4.1 × 10−5 mm3·N−1·m−1) among all composites.

scholarly journals Effects of Reduced Graphene Oxide (rGO) at Different Concentrations on Tribological Properties of Liquid Base Lubricants

Lubricants ◽  
2019 ◽  
Vol 7 (2) ◽  
pp. 11 ◽  
Author(s):  
Jankhan Patel ◽  
Amirkianoosh Kiani
Keyword(s):  
Graphene Oxide ◽  
Physical Properties ◽  
Reduced Graphene Oxide ◽  
Tribological Properties ◽  
High Speed ◽  
Friction And Wear ◽  
Control Sample ◽  
Wear Properties ◽  
Reduced Graphene ◽  
Friction And Wear Properties

In this study, reduced graphene oxide (rGO) nano platelets were used as an additive to enhance friction and wear properties of oil-based lubricants by preparing three samples at 0.01% w/w, 0.05% w/w, and 0.1% w/w concentrations. To analyze the direct effect of rGO nano platelets on tribological properties, 99.9% pure oil was used as a liquid lubricant. A comparative tribological study was done by performing a ball-on-disk wear test in situ under harsh conditions, which was further analyzed using a non-contact 3D optical profilometer. Morphological evaluation of the scar was done using transmission and scanning electron microscopy (TEM, SEM) at micro and nano levels. The lubricants’ physical properties, such as viscosity and oxidation number, were evaluated and compared for all samples including pure oil (control sample) as per ASTM standards. Findings of all these tests show that adding rGO nano platelets at 0.05% w/w showed significant reduction in friction at high speed and in wear up to 51.85%, which is very promising for increasing the life span of moving surfaces in machinery. Oxidation and viscosity tests also proved that adding rGO nano platelets to all samples does not sacrifice the physical properties of the lubricant, while it improves friction and wear properties.

A Study on Wear Properties of GCV Material with DLC Coating

2013 ◽  
Vol 470 ◽  
pp. 7-10
Author(s):  
Ki Woo Nam ◽  
Soo Chul Lee
Keyword(s):  
Cast Iron ◽  
Friction Coefficient ◽  
Coating Layer ◽  
Wear Test ◽  
High Hardness ◽  
Wear Properties ◽  
Dlc Coating ◽  
Insulating Properties ◽  
Partial Damage ◽  
Grey Iron

Compacted vermicular (CV) graphitization cast iron is the name given to graphitization cast iron where the shape of the graphite looks like a vermicular. Castability and the thermal conductivity of CV graphitization cast iron is similar to those of Grey iron, while the strength of CV graphitization cast iron is similar to that of ductile iron. The thin film of diamond-like carbon (DLC) is one of the amorphous carbon thin films. It has various characteristics which are similar to those of diamond, such as high hardness, lubricity, abrasion resistance, chemical stability, electrical insulating properties and optical transparency. In this study, wear characteristics of Graphite Compacted Vermicular (GCV) material were investigated in accordance with changes in DLC coating time. The obtained results are as follows: the microstructure of GCV340 showed complex tissue with eccentric graphite and spherical graphite. The friction coefficient shows under 0.2 in all specimens. After enduring the wear test until 2000 m, the coating layer of the DLC coating specimen of 90 minute hardly showed any damage. It had only partial damage after taking the wear test until 2000 m. The friction coefficient was also the lowest.

Alkali treatment and its effect on tribological properties of natrually woven coconut sheath polyester composite

2014 ◽  
Vol 4 (2) ◽  
Author(s):  
I. Siva ◽  
J.T. Winowlin Jappes ◽  
Z. Szakal ◽  
Jacob Sukumaran
Keyword(s):  
Tribological Properties ◽  
Hybrid Composites ◽  
Alkali Treatment ◽  
Low Cost ◽  
Alkaline Treatment ◽  
Natural Fibres ◽  
Tribological Behaviour ◽  
Wear Properties ◽  
Low Friction ◽  
Sem Images

In the recent years natural fibres have drawn great interest for its bio-degradability, low cost and its availability in nature. Among different types of natural fibres, naturally woven coconut sheath fibres are one of the recently explored alternatives for synthetic fibres. These fibres are generally treated with alkali for enhancing mechanical properties and reinforcing characteristics. Tribological applications like gears, cams, bearings, etc. can be benefited from such composites. In most cases chemical treatment are done favouring the structural properties however, their influence on tribological properties are rather not considered. In the current research, hybrid composites (polyester resin with naturally woven coconut sheath (N) and glass fibres (G)) were tested against hardened steel counterface in a pin on disc configuration. Tests were performed at 40 N normal force and 3.5 m/s sliding velocity. From the results all hybrid combinations except (NNN) shows degrading wear properties with the alkaline treatment. The friction properties are modified by having low friction coefficients for all combinations except NGN and GGG hybrids. From the observed SEM images the surface morphology of NNN hybrid significantly differs from the rest of the combinations in both treated and untreated specimens. The partial removal of individual phase (resin) prevails in untreated specimen for which the fibres are highly visible. However, such phenomenon is not dominant in the alkali treated material showing better reinforcing behaviour complimenting low friction properties. The alkali treated specimen has reduced fibre size comparing the untreated specimen which results in low wear resistance. Compromise between friction and wear properties between each other the untreated fibres are best suited for tribological applications. Furthermore, investigations on treatment process and other treatments might have some influence in tribological behaviour.

Quaternary–matrix, nanocomposite self-lubricating PVD coatings in the system TiAlCN-MoS2 – structure and tological properties

2003 ◽  
Vol 788 ◽  
Author(s):  
V. Spassov ◽  
A. Savan ◽  
A. R. Phani ◽  
M. Stueber ◽  
H. Haefke
Keyword(s):  
Friction Coefficient ◽  
High Speed ◽  
High Hardness ◽  
Scratch Test ◽  
Hard Coatings ◽  
Work Piece ◽  
Low Friction ◽  
Dry Cutting ◽  
Productivity Cost ◽  
Temperature Oxidation

ABSTRACTNowadays the demands placed upon the tooling in processes such as cutting, drilling, milling, stamping, bending, etc. are constantly growing and restrictive. On one hand, productivity, cost efficiency and quality all require high-speed processes to be developed. On the other hand, environmental safety requires very little or no lubricant to be used (dry cutting or minimized spray-lubrication). When combined, these two considerations mean: the tool should wear very little, withstand high temperatures and the friction between the tool and the work piece should be minimized. An apparent approach to simultaneously satisfying such requirements is coating the tools with self-lubricating hard coatings. Quaternary TiAlCN is a rapidly developing hard coating suitable for a number of cutting applications. The well-known wear-resistant coating TiN has been demonstrated to have improved high-temperature oxidation resistance when aluminum is included, i.e. TiAl N. Addition of yet a fourth element, carbon, has the primary effect of lowering the high friction coefficient occurring between the ceramic coating and steel. The high hardness, toughness, heat resistance and low friction coefficient of TiAlCN make it the ideal candidate for applications such as milling, hobbing, tapping, stamping and punching. MoS2 is a well-known solid lubricant widely used as tribological coatings, especially for applications working in vacuum or dry environment. Combining the wear resistance of the quaternary TiAlCN matrix with the lubricating properties of MoS2 has an extremely beneficial effect in further improving the tribological performance of the resulting composite. The coatings were deposited on hardmetal (WC-Co) and Si (100) substrates using reactive magnetron sputtering. The structure of the coatings is studied by plain-view TEM and XTEM, electron diffraction and ED X. The tribological properties were examined by Pin-on-Disk (PoD) tribometer. The adhesion was estimated by scratch test, and the hardness was measured by nanoindentation. All the coatings examined had a very low friction coefficient (typically below 0.09) and volumetric wear rate against 100Cr6 steel (AISI 52100) of 7.10-7 mm3/N/m. The relation of deposition parameters to structure to properties is discussed. To the authors knowledge, this is the first paper describing quaternary TiAlCN matrix with inclusions of MoS2.

Assessment of Tribological Properties of Low Friction Thin Layers Produced by Vacuum Methods

2019 ◽  
Vol 293 ◽  
pp. 125-140
Author(s):  
Agnieszka Paradecka ◽  
Krzysztof Lukaszkowicz ◽  
Jozef Sondor
Keyword(s):  
Wear Resistance ◽  
Friction Coefficient ◽  
Chemical Analysis ◽  
Coefficient Of Friction ◽  
Tribological Properties ◽  
Structural Changes ◽  
Thin Layers ◽  
Low Friction ◽  
Topographic Analysis ◽  
Steel Substrates

Low friction thin layers are an excellent alternative for conventional coatings. They provide increased life of the elements, to which they were applied, due to enhancing the hardness or chemical and electrochemical resistance. They help to avoid the cracks, oxidation, as well as possible structural changes during the element's work. However, they primarily improve tribological properties by increasing wear resistance and reducing the friction. This also applies to components operating under variable conditions such as load, speed, temperature. The presented article analyzes the properties of various low-friction thin layers deposited by vacuum methods on the steel substrates. DLC, TiC, MoS2, CrCN thin layers were chosen, as they achieve the lowest possible coefficient of friction. In the framework of this work the measurements of adhesion of the investigated layers to the substrate as well as the friction coefficient, chemical analysis, microstructure and topographic analysis of the low-friction layers were carried out.

scholarly journals Effect of sp3 Content on Adhesion and Tribological Properties of Non-Hydrogenated DLC Films

Materials ◽  
2020 ◽  
Vol 13 (8) ◽  
pp. 1911 ◽  
Author(s):  
Chao Li ◽  
Lei Huang ◽  
Juntang Yuan
Keyword(s):  
Friction Coefficient ◽  
Magnetron Sputtering ◽  
Adhesion Strength ◽  
Bias Voltage ◽  
Tribological Properties ◽  
Scratch Test ◽  
Graphite Target ◽  
Transfer Layer ◽  
Xps Spectra ◽  
Pure Graphite

Non-hydrogenated diamond-like carbon (DLC) films with various ratios of sp3/sp2 were prepared on cemented carbide YG8 with DC magnetron sputtering technology. A pure graphite target was selected as the carbon source. Before DLC deposition, a surface etching pretreatment was carried out by mid-frequency magnetron sputtering method, using Ti atoms to improve adhesion strength. The ratios of sp3/sp2 were adjusted by bias voltages. In order to investigate the effect of the ratio of sp3/sp2 on adhesion and tribological properties, Raman spectra, XPS spectra, adhesion scratch test and ball-on-disk dry friction tests were applied. The results indicated that the ratio of sp3/sp2 fluctuated with bias voltage, increasing in the range of 0.74 to 0.98. The adhesion strength decreased from 31.5 to 18.4 N with the increasing ratio of sp3/sp2, while the friction coefficient rose in DLC-Si3N4 and dropped in DLC-Ti6Al4V. For DLC-Ti6Al4V, the oxidation of Ti6Al4V had a greater influence than graphitization of DLC. The hard oxides of Ti6Al4V broke the graphite transfer layer leading to a high friction coefficient. The wear rate was approximately linearly related to bias voltage. The coefficients of the linear regression equation were influenced by different friction materials. The adhesion strength and the friction coefficient were fitted as a function of the ratio of sp3/sp2.

scholarly journals The gas-dynamic antifriction coating of babbitt for bearings of the turbine rotor

2019 ◽  
Vol 298 ◽  
pp. 00036
Author(s):  
Irina Tsareva ◽  
Olga Berdnik ◽  
Lyudmila Krivina ◽  
Yuri Levanov
Keyword(s):  
Friction Coefficient ◽  
Service Life ◽  
Adhesion Strength ◽  
Turbine Rotor ◽  
Low Friction ◽  
Antifriction Coating ◽  
Sliding Bearings ◽  
Gas Dynamic ◽  
Working Surface ◽  
High Adhesion

The application of the anti-friction coating of babbitt on the working surface of sliding bearings is an important technological procedure necessary both for their manufacture and for their repair. To extend the service life and restore the performance of bearings, the coating is preferably applied by gas-dynamic spraying, The coating formed by this method has a low porosity, high adhesion strength and low friction coefficient.

Sign in / Sign up

Export Citation Format

Share Document