scholarly journals Durability of working bodies of soil-cultivating machines strengthened by composite electrolytic coatings (CEC)

2021 ◽  
Vol 100 (2) ◽  
pp. 41-49
Author(s):  
M. Stechyshyn ◽  
A. Kornienko ◽  
N. Stechyshyna ◽  
A. Martynyuk ◽  
M. Tsepeniuk ◽  
...  

The task of this work is to find the optimal ratio between the size of the particles of silicon carbide and their volumetric content in the nickel matrix to provide maximum characteristics of strength and wear resistance of the working bodies of soil-processing machines. The article investigates the processes of forming complex electrolytic coatings (CEC) on a nickel basis with particles of the filler of various sizes of silicon carbide (SIC). It has been established that the formation of a sicle size sicle and SiC5 is carried out on a vertical, and all other particles in a horizontal cathode. The volumetric content of SICnano and SiC5 particles in nickel reaches a maximum of about 10%, and SiC100 – 46 %. Cap with particle size 28/20 and 50/40 μm allow you to get the most wear-resistant coatings. In this case, the coating with particles 28/20 μm have higher wear resistance, but coating with particles 50/40 μm are more technological when they are formed. The size of the filler particles has a significant effect on the tribological characteristics of the CEP, namely wear resistance and friction coefficient. It has been established that the highest wear resistance and the smallest friction coefficients are characterized by coatings having as a filler of fractions 28/20 and 50/40 μm. Tribological studies show the promise and efficiency of the CEP to increase the wear resistance of the working bodies of soil-cultivating machines.

Author(s):  
Dmitriy B. Slinko ◽  
Vyacheslav A. Denisov ◽  
Dmitriy A. Dobrin ◽  
Andrey V. Afanas’yev ◽  
Pavel M. Kislov

Reducing operating costs during soil processing and increasing the wear resistance of parts and components is an important condition for reducing the cost of agricultural products, increasing its efficiency and competitiveness. The development of materials with increased wear resistance and new effective technologies for strengthening working bodies in their manufacture is now becoming an urgent task. (Research purpose) The research purpose is increasing the wear resistance of the working bodies of soil-processing machines by electric arc surfacing. (Materials and methods) During the experimental study, it has been performed testing of modes and surfacing of a pilot batch of working bodies from Kverneland for field tests in VIM on an automated installation for electric arc surfacing. Authors used eutectic CastolinEnDotec DO*30 powder wire with a diameter of 1.2 millimeters and a boron content of up to 4 percent for surfacing wear-resistant rollers, which allows to obtain wear-resistant rollers with a hardness of up to 65 HRC without pores and cracks. (Results and discussion) It has been revealed that hardened ploughshares that have passed field tests are subject to lower wear rates compared to non-hardened ones. It was found that when operating time is 24.785 hectares per ploughshare, the wear of the linear size of the cutting edge along the width of hardened ploughshares is on average up to 10-11 millimeters less than that of non-hardened ones. It was found that when processing 228 hectares, the wear of the linear size of the cutting edge along the width of hardened bits is on average up to 9-10 millimeters less than that of non-hardened ones. (Conclusions) The technology of surfacing with intermittent wear-resistant rollers provides an increase in the efficiency of hardening of Kverneland working bodies according to the criterion of wear resistance by an average of 20-30 percent. The adjusted technological parameters of the surfacing process will reduce the wear rate and increase the service life of the blade part of the working bodies, as well as reduce the amount of surfaced material by an average of 60 percent. The continuation of work on strengthening the working bodies should be aimed at changing the surfacing scheme and choosing a cheaper domestic cored wire.


2012 ◽  
Vol 452-453 ◽  
pp. 16-20
Author(s):  
Jun Yan ◽  
Hong Guang Li ◽  
Hai Ping Cui ◽  
Ming Qiu Wang ◽  
Shi Guo Du

Author(s):  
Traugott E. Fischer ◽  
Yunfei Qiao ◽  
YouRong Liu

The wear resistance of thirty WC-Co coatings, deposited by standard High-Velocity Oxyfuel (HVOF) techniques and a high-temperature variant of HVOF, with standard commercial and experimental nanostructured feedstocks, is examined. It is found that the high-temperature gun produces harder and more wear-resistant coatings than the standard gun. The latter does not generate high enough temperatures to melt the powder and provide good bonding between WC grains and Co binder. All coatings present higher wear resistance than the steel substrate. Coatings deposited with standard feedstock possess generally higher wear resistance than nanostructured coatings. The difference is more pronounced in sliding than in abrasive wear. WC-Co Coatings deposited with nanostructured feedstocks are recommended for use in bearings and other machinery with sliding parts because they inflict much less wear on the material on which they slide than conventional coatings. Coatings with micrometer WC grains are recommended for abrasion resistance applications such as earth moving or slurry processing machinery.


2016 ◽  
Vol 851 ◽  
pp. 112-116
Author(s):  
Xing Hui Li

A resin matrix compound coating is prepared by taking epoxy as the matrix and α-Al2O3 particle as the reinforced phase. By simulating the actual wear conditions of pipes in the heavy medium coal preparation in a laboratory, the paper explored the change law of the erosion wear resistance of wear-resistant coating with different reinforced particle sizes and abrasion angles, and discussed the wear mechanism by combining with abrasive appearances. The results show that reinforced particles with a lager particle size (60 mesh) are of excellent erosion wear resistance when the erosion wear particle is smaller (200 mesh), and the α-Al2O3 particle wear-resistant epoxy coating with a particle size of 60-80 mesh is of good erosion wear resistance under the condition of heavy medium coal preparation and is suitable to be a wear-resistant coating material.


Author(s):  
Yanchao Zhang ◽  
Chenguang Si ◽  
Yongtao Zhang ◽  
Dongya Zhang ◽  
Yahui Cui

Finger seals provide favourable flexible dynamic performance and a low level of leakage that is less than that of brush seals and graphite seals. However, the hysteresis caused by the friction between different finger slices or between the finger slice and the back plate strongly affects the working stability. In addition, the wear properties between the finger feet and rotor runway can adversely affect the working stability. Based on the tribological mechanism, wear-resistant coatings can provide a satisfactory solution to these problems. For this purpose, the simulations of finger seal are first performed in ANSYS to verify that good contact surface friction performance can effectively improve the efficiency of finger seal. Then we evaluated the friction performance of WC, Cr3C2, and PTFE coatings using a pin-on-disk tribometer. The results showed that the wear-resistant coatings generally exhibited better wear resistance than the substrate material under various load conditions (correspond to the bench test PV of finger seal). The friction coefficient of the 40CrNiMoA substrate was 0.65, while the friction coefficients of WC, Cr3C2, and PTFE coatings were 0.22, 0.27, and 0.13, respectively, corresponding to 33.8%, 41.5%, and 20% of the friction coefficient of the 40CrNiMoA substrate. The friction coefficient of the PTFE coating was the lowest due to its self-lubricating property and showed a long service life under low loads; thus, this coating offers a promising solution to reduce the friction-caused hysteresis on a finger seal. Under loads of 20 N and 30 N, the service life of the WC coating was much longer than that of the Cr3C2 coating. Even at a load of 50 N, the service life of the WC coating was 4.3 times that of the Cr3C2 coating. The wear-resistant WC coating has strong application prospects in improving the service life of finger seals.


2008 ◽  
Vol 403 ◽  
pp. 115-116
Author(s):  
Qian Liu ◽  
Lin Hua Gui ◽  
Jun Hu Meng ◽  
Zhi Feng Li

A considerable test was made to figure out the effects of temperature and sliding conditions on the wear properties of the translucent Dy--Sialon. The friction coefficient was 0.54 at RT, 0.26 at 100 oC, and 0.81 at 600 oC respectively under an applied load of 5N. The wear rate was 6.91×10-15 at RT and 1.0×10-15 at 100 oC for the same Dy--Sialon sample. Obviously Dy-Sialon shows an excellent wear resistance under a suitable sliding condition, a load of 5N and at 100 oC. This appears attractive and important for Dy-Sialon ceramics to be used as a type of special wear resistant materials, with an optical translucence.


2016 ◽  
Vol 703 ◽  
pp. 119-122
Author(s):  
Zeng Rong Li ◽  
De Yuan Li ◽  
He Huang ◽  
Bi Wu

An arc spray gun with inner holes was used to spray two typical iron-based wear-resistant coatings, 08A and 08CrMoVA, on the inner wall of an aluminum cylinder block for an engine. In addition, microstructures of the coatings were observed through an optical microscope and a scanning electron microscope. Then, X-ray diffraction (XRD) patterns were employed to analyze the types of oxides in the coatings, and a quantitative metallographic analyzer was applied to test the porosity and the amount of oxides in the coatings. Afterwards, the coatings were immersed in the oil to conduct the wearing test and the test result showed that the coatings had better wear resistance, compared with the gray cast iron. Besides, it was further found that the coatings were formed on the substrate surface by the accumulation of flat particles, and unmelted particles, oxides, pores and fissures were also found in the coating layer. While being lubricated by oil, FeO in the coatings and the oil stored in pores decreased the friction coefficient and thus increased the wear resistance of the coating layer.


2012 ◽  
Vol 622-623 ◽  
pp. 787-790
Author(s):  
Prem Ananth Muthuvel ◽  
Rajagopal Ramesh

Industrial application of sliding components required to improve the tribological properties by increasing the surface hardness, friction and wear resistance. Modern modification of surface layers for friction applications combines surface texturing and filling of textured layers by wear resistant coatings of various compositions to improve its functional aspect and enhanced service life. Texturing of contact surfaces has a remarkable influence on their tribological properties, especially in the effect of wear and friction. This work proposes the coating of nano sized Titanium Aluminum Nitride (TiAlN) by Magnetron Sputtering-Physical Vapour Deposition (PVD) on the Titanium alloy (6Al-4V) substrate and study the performance of the coated surfaces by pin on disc tribometer. Two kinds of substrates were prepared one is the lapped surface and the other one is the textured surface by Laser beam machining. The Tribological performance of the wear resistant coatings on lapped and textured surfaces was experimentally investigated under various normal load conditions and the results were compared. Critical parameters such as friction coefficient, wear rate, wear volume, wear morphology and micro wear mechanism were investigated in this work. The coating surfaces and wear scars were evaluated by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDAX). The results showed that the TiAlN coating on textured surfaces exhibited lower friction coefficient and wear rate than the TiAlN coating on lapped surfaces under same testing conditions.


2007 ◽  
Vol 353-358 ◽  
pp. 1580-1583
Author(s):  
Han Ning Xiao ◽  
Ji Xiang Yin ◽  
Tetsuya Senda

Friction and wear tests of TiB2 sliding against SiC were conducted without lubricant from room temperature to 1200°C in air and in vacuum. The friction coefficient of the couple of TiB2/SiC is affected obviously by the oxidation of TiB2. It increases with the increase of temperature and reaches a maximum at some temperature in air, then decreases remarkably. The friction coefficient of TiB2/SiC in vacuum exhibites almost a constant and keeps smaller value than that in air. Transition of TiB2 onto the sliding surface of SiC was observed, which improved the wear resistance of SiC at high temperatures.


Sign in / Sign up

Export Citation Format

Share Document