WEAR MECHANISM MAP OF MAGNESIUM ALLOY COATED WITH WC/CU ELECTRODE USING ELECTRO DISCHARGE ALLOYING

2019 ◽  
Vol 14 (1) ◽  
Author(s):  
Elaiyarasan U ◽  
Satheeshkumar V ◽  
Senthilkumar C

The objective of this research is to study the wear mechanism of ZE41A magnesium alloy coated with WC/Cu material using EDC (Electro discharge coating). Dry sliding experiments were conducted with pin on disc method with different sliding condition such as normal load (1.5 kg - 3.5 kg), sliding speed (100rpm - 300 rpm) and sliding time (3min - 7min). Wear mechanism map was drawn against sliding condition of normal load and sliding speed which has been utilized to study the dominance of particular wear mechanism that dominates a particular wear regime. Different wear regime such as mild wear, severe wear ultra severe wear was developed by adjustment of contour line of the wear rate map. Various mechanisms such as abrasion, oxidation, delamination, plastic deformation and melting were observed in the worn surface

2020 ◽  
Vol 12 (8) ◽  
pp. 1028-1033
Author(s):  
U. Elaiyarasan ◽  
V. Satheeshkumar ◽  
C. Senthilkumar

The present investigation studied the dry sliding wear behavior of WC–Cu deposited ZE41A magnesium alloy under various parameters such as normal load, sliding speed and sliding time and the responses are wear rate and coefficient of friction. In this investigation, WC–Cu deposited magnesium alloy specimens were tested using pin on disc apparatus against EN31 steel disc. Wear mechanism map is developed for wear rate of the deposited magnesium alloy against normal load and sliding speed to identify the different wear modes such as mild, severe and ultra sever wear. Worn surface samples is assessed by Scanning Electron Microscope (SEM) and Energy Dispersive Spectroscope (EDS) to confirm the different wear mechanism such as abrasion, oxidation, delamination and melting. Normal load is identified as the most dominant process parameter in this experiment. Magnesium alloy deposited using WC–Cu composite coating by EDC improved the wear behavior in the lower ranges of sliding conditions.


2011 ◽  
Vol 704-705 ◽  
pp. 877-885
Author(s):  
San Ming Du ◽  
Yong Zhen Zhang ◽  
Bao Shangguan

Abstract: In this article, the high-speed dry sliding tribological behaviors of CrNiMo steel against brass in nitrogen and oxygen atmospheres are investigated using a pin-on-disc tribometer. The worn surface is characterized by scanning electron microscopy and electron dispersion spectrums analysis. The wear mechanisms of CrNiMo steel are also analyzed. The results indicate that the tribological properties of CrNiMo steel are coincidental with the law of dry sliding of metal, where the friction coefficients decreases with an increase in sliding speed and with normal load. However, the atmosphere has obvious effects on the tribological properties of CrNiMo steel. In the sliding process, friction heat plays an important role on the tribological properties of materials in high-speed dry friction. The high-speed wear mechanism of CrNiMo steel varies at different atmospheres. In a nitrogen atmosphere, the wear mechanism of CrNiMo steel is mainly characterized by adhesion at a lower speed and load. When the speed and load are increased, melting trace is found in the worn surface accompanied by an abrasive wear. In an oxygen atmosphere, the mechanism is characterized by adhesion at a lower speed and load; with an increase in speed and load, it gradually transformed into oxidation wear and abrasive wear. The difference of the wear mechanisms in the different atmospheres and test parameters is primarily due to the transfer films formed on the contact surfaces of the sliding pairs. In our experimental conditions, the surface film is mainly the metal film in nitrogen, whereas, it is the oxide film in oxygen.


2014 ◽  
Vol 692 ◽  
pp. 282-287 ◽  
Author(s):  
Xin Wang ◽  
Rong Bin Li ◽  
Jing Zhang

The dry sliding friction test of normalized T10 steel against hardened quenched and tempered 20CrMnTi steel under normal load of 60 N and sliding speed of 0.29m/s was carried out on a pin-on-disc tribo-tester. The microstructures in the worn surface layer of T10 steel pin and 20CrMnTi steel disc were analyzed by OM, SEM, and TEM, which were all severely plastically deformed. The ultrafine and even nanoferrite grains (5 nm to 200 nm) were observed in the worn surface layer of T10 steel pin, which was considered to be the result of severely shear deformation.


Author(s):  
M. Ruiz-Andrés ◽  
A. Conde ◽  
J. de Damborenea ◽  
I. García

The investigated slow sliding speeds presented in this work enable the understanding of the wear behavior on aluminum alloys and could possibly facilitate the completion of the previously proposed wear mechanism map for aluminum at this slow sliding speed range. Dry sliding block-on-ring wear tests were carried out on aluminum alloys, AA5754 (Al-Mg), AA6082 (Al-Mg-Si), and AA7075 (Al-Zn-Cu), at a very slow sliding speed range (<0.01 m/s). A bearing steel ring of AISI 52100 was used as the counterbody. Tests were performed at varying contact pressures, 20, 100, and 140 MPa, and sliding speeds ranging from 0.001 to 1.5 m/s. The wear tracks and debris collected were examined by scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and X-ray diffraction (XRD), with the aim of analyzing their morphology and composition. At relatively slow sliding speeds (>0.01 m/s), the specimens exhibited a wear process placed at the mild wear regime, characterized by oxidation and delamination mechanisms of both the aluminum specimen and the steel ring. However, at very slow speed range (<0.01 m/s), an increase in the wear rate and the friction coefficient is observed for all of the aluminum alloys, thus suggesting that an alternative wear mechanism could be taking place.


Author(s):  
S.R. Ruban ◽  
K.L.Dev. Wins ◽  
J.D.R. Selvam ◽  
A.A. Richard

This paper investigates the dry sliding wear behaviour of AA6061/ZrB2/SiC hybrid composite prepared by the stir casting. A pin-on-disc wear apparatus was used for this study. The effect of ZrB2 and SiC particulate content and normal load on wear rate was analyzed. The insitu fabricated ZrB2 and the reinforced SiC particles enhance the wear resistance of the AA6061 composite. The worn surface analysis of the composite as a function of ZrB2 and SiC particulate content and normal load are also presented.


2014 ◽  
Vol 592-594 ◽  
pp. 1305-1309 ◽  
Author(s):  
K. Rajkumar ◽  
S. Aravindan

Effects of graphite content, and sliding speed on the tribological characteristics of copper-graphite composites under dry sliding condition were evaluated using a pin-on-disc tribometer. The worn surfaces of the composites were analyzed through Scanning Electron Microscopy (SEM). The experimental results revealed the improvement in wear resistance with increasing graphite content. The friction coefficient is also gradually decreasing upto 25 vol% graphite. Sliding speed has an effect on copper (5-15 vol%) graphite composites where as sliding speed has no effect in copper-(20-30 vol%) graphite composites. This difference is attributed to availability of self-lubricating graphite layer at the contact zone.


Author(s):  
Ajith Kurian Baby ◽  
M Priyaranjan ◽  
K Deepak Lawrence ◽  
PK Rajendrakumar

Hypereutectic Al-Si alloys are used as material for the engine block and cylinder liners in automobiles. Wear behaviour of hypereutectic Al-Si alloy system changes significantly with applied normal load in both mild wear and severe wear regime. Significant improvement in wear resistance can be obtained by exposing silicon particles through the chemical etching process. For Al-25% Si alloys, most studies are reported in mild and ultra-mild wear regime. In the present work, the wear of exposed silicon particles with varying load and speed in severe wear regime was investigated under the unidirectional sliding condition and bi-directional sliding condition using a pin-on-disk tribometer (POD) and a linear reciprocating tribometer (LRT), respectively. Rapidly solidified and T6 heat-treated Al-25Si alloy was polished and etched using 5% NaOH solution to expose the silicon particles. Experiments were carried out with normal loads varying from 40 N to 120 N in dry sliding conditions. Sliding speeds of 0.8 m/s and 1.5 m/s were applied for each load in case of a pin on disk tribometer whereas, in an LRT, the sliding velocities were 0.2 m/s and 0.45 m/s respectively for each set of the load. The surface topography was measured by means of a 3-D optical profilometer, and surface morphology was analyzed using SEM images. It was observed that at higher loads, larger Si particles were fractured and pushed into the matrix. Fractured silicon particles, along with smaller particles, were embedded into the matrix, thereby increasing the silicon concentration in the wear region. The comparison of the experimental results of unidirectional and bi-directional sliding that reveal the change in surface morphology of silicon particles, the friction characteristics at the interface, variation of surface 3-D roughness parameters, the wear rate and wear mechanisms of Al-25% Si alloys are analyzed and reported in the study.


Wear ◽  
2008 ◽  
Vol 265 (5-6) ◽  
pp. 685-691 ◽  
Author(s):  
J. Wang ◽  
Y.B. Liu ◽  
J. An ◽  
L.M. Wang

2014 ◽  
Vol 554 ◽  
pp. 396-400 ◽  
Author(s):  
Samion Syahrullail ◽  
Noorawzi Nuraliza

In the present of analysis, the wear rate and friction coefficient of various material is investigated and it were compared below the result of sliding speed wherever the equipment pin on disk machine has been used. Experiments were carried out with 2 totally different pins fabricated from aluminum alloy (AA5083) and pure aluminum (A1100). Experiments were conducted at normal load in step with according to testing, 10 N with totally different sliding speed 1, 3, 5 m/s ,continuous flow lubricating substance, double fraction palm olein (DFPO). The result shows that the material from pure aluminum higher material compared to the aluminum alloy in sliding condition. The morphology of the worn surface was ascertained using high optical research. The magnitude of the friction constant and wear rate are totally different in material depending on the speeds and additionally material.


2007 ◽  
Vol 539-543 ◽  
pp. 797-802
Author(s):  
B.M. Satish ◽  
B.M. Girish

The wear behavior of unreinforced as well as feldspar particles reinforced copper alloy (phosphor-bronze) composites was studied as a function of sliding speed and applied loads under unlubricated conditions. The content of feldspar particles in the composites was varied from 1- 5% by weight in steps of 2%. A pin-on-disc wear tester was used to evaluate the wear rate. Loads of 20-160 N in steps of 20 N and speeds of 1.25, 1.56, and 1.87 m/s were employed. The results indicated that the wear rate of both the composites and the alloy increased with increase in load and sliding speed. However, the composites exhibited lower wear rate than the alloy. It was found that above a critical applied load, there exists a transition from mild to severe wear both in the unreinforced alloy and in the composites. But the transition loads for the composites were much higher than that of the alloy. The transition loads increase with the increase in weight % of feldspar particles, but decreases with the increase in sliding speeds.


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