Tribological Characteristics of Deformed Magnesium Alloy AZ61 Under Dry Conditions

2011 ◽  
Vol 133 (4) ◽  
Author(s):  
Abdel-Wahab El-Morsy ◽  
A. Abouel-Kasem

The wear behavior of deformed magnesium alloy AZ61 under dry conditions was evaluated. Two types of AZ61 alloy were used, extruded and rolled samples, to investigate the effect of deformation process on the wear behavior. The experiments were performed using a pin-on-ring type wear apparatus against a stainless-steel counterface under applied stresses in the range of 3–7 MPa, and within a sliding velocity range of 0.2–1.8 m/s. The topographical images of the eroded surfaces at different sliding velocity for extruded and rolled samples were quantified using fractal analysis. The results revealed that for all applied stress, the wear rates increased with increasing the sliding velocity of both samples. The wear rate of the rolled samples is greater than that of the extruded samples at the stress range from 3 to 5 MPa. However, when the stress is increased to 7 MPa the wear rate of the rolled samples is lower than that of the extruded samples. The variation of fractal value of slope of linearized power spectral density (PSD) with the sliding velocity is largely similar to the relationship between the wear rate and the sliding velocity.

2020 ◽  
Vol 835 ◽  
pp. 155-162
Author(s):  
Malak Abou El-Khair ◽  
Fatma Firouz ◽  
Ahmed Lotfy ◽  
Essam Mohamed ◽  
Atef Daoud

An attempt has been made to investigate the microstructures and wear behavior of magnesium alloy AM100 (Mg-Al-Mn) based composites reinforced with 7 vol. % of ZrB2, graphite or hybrid of (1:1) ZrB2 and graphite particles as well as the unreinforced magnesium alloy. Magnesium alloy was melt under shield of inert gases and composites were prepared using stir casting method. Optical microscopy was used to study the microstructures of the unreinforced alloy and composites. The composites characterized primarily by the uniform distribution of particles in the matrix and a good adherence between the particles and matrix. XRD analysis was used to identify the phases of the unreinforced alloy and composites. The XRD diffraction pattern of AM100 matrix reveals different phases, namely, Mg, AlMn and Al12Mg17. Formation of these phases is due to the reaction between alloy constituents. Dry sliding wear tests were conducted by using a pin-on-ring apparatus. The wear rates of the composites and matrix alloy were measured at loads of 10, 20 and 30 N, and sliding speed of 0.7 m/s. The worn surfaces of the composite pins were examined by scanning electron microscopy (SEM). The experimental results of the wear tests showed that the magnesium based composites exhibited higher wear rate at all the applied loads when compared to those of the unreinforced magnesium alloy. The ZrB2 reinforced magnesium composite exhibited the lowest wear rate amongst the composites material investigated in the present work.


2010 ◽  
Vol 45 (6) ◽  
pp. 683-693 ◽  
Author(s):  
Bin Hu ◽  
Liming Peng ◽  
Wenjiang Ding

Dry sliding wear behavior of the creep-resistant magnesium alloy Mg-10Gd-3Y-0.5Zr and its composites have been investigated in this study. Magnesium matrix composites are prepared by squeezing casting infiltration of Mg alloy into Saffil preforms. Wear tests are conducted using ball-on-flat sliding wear set up under a sliding velocity range of 1-15 cm/s and at an applied load range of 1-8 N for a constant sliding distance of 150 m. According to results, mechanical and wear-resistance properties of magnesium alloy improved by introducing Saffil fibers, and the alumina binder composite has a higher strength and lower wear rate than silica binder composite. The wear rates of the matrix alloy, composites and their counter-face balls increase with increasing applied load. The increment of sliding velocities decreases the wear rate of the matrix alloy under the tested sliding velocities. A critical threshold of sliding velocity for the wear rate of both composites and their counter-faces is about 9 cm/s. Abrasion and plastic deformation are considered to be the dominant mechanism for the matrix alloy in tested conditions, and for both composites under low sliding velocity (<10 cm/s) and at low applied loads (1-5 N). Delamination is the wear mechanism of the silica binder composites at a high applied load (8 N). Adhesion and oxidation are the controlling wear mechanism of matrix alloy and composites under a sliding velocity of 15 cm/s.


2020 ◽  
Vol 22 (4) ◽  
pp. 1031-1046
Author(s):  
X. Canute ◽  
M. C. Majumder

AbstractThe need for development of high temperature wear resistant composite materials with superior mechanical properties and tribological properties is increasing significantly. The high temperature wear properties of aluminium boron carbide composites was evaluated in this investigation. The effect of load, sliding velocity, temperature and reinforcement percentage on wear rate was determined by the pin heating method using pin heating arrangement. The size and structure of base alloy particles change considerably with an increase of boron carbide particles. The wettability and interface bonding between the matrix and reinforcement enhanced by the addition of potassium flurotitanate. ANOVA technique was used to study the effect of input parameters on wear rate. The investigation reveals that the load had higher significance than sliding velocity, temperature and weight fraction. The pin surface was studied with a high-resolution scanning electron microscope. Regression analysis revealed an extensive association between control parameters and response. The developed composites can be used in the production of automobile parts requiring high wear, frictional and thermal resistance.


2007 ◽  
Vol 124-126 ◽  
pp. 1573-1576
Author(s):  
Jeong Keun Lee

The tribological behavior of TiC-based metal matrix composites was investigated via measuring counterpart weight. The composites were prepared using powder metallurgy technique. Wear of counterpart by the composites varying from 35 to 45 % by volume Titanium carbide were observed over a load ranges of 9.81 to 49.05 N and sliding velocities of 2.0, 2.2, 2.4, 2.6, 2.8 and 3.0 m/sec. Detailed wear track micro-graphy was done to verify the effect of sliding condition on wear mechanism. Observations indicate that wear rate of counterpart increases with the increase in load and the sliding velocity and discontinuous wear rate change occurs at a certain load.


2009 ◽  
Vol 423 ◽  
pp. 125-130 ◽  
Author(s):  
Alvaro Mestra ◽  
Gemma Fargas ◽  
Marc Anglada ◽  
Antonio Mateo

Duplex stainless steels contain similar amounts of austenite  and ferrite α. This two-phase microstructure leads to an excellent combination of mechanical properties and corrosion resistance. However, there are few works dealing with the wear behaviour of these steels. This paper aims to determine the sliding wear mechanisms of a duplex stainless steel type 2205. In order to do it, three different sliding velocities (0.2, 0.7 and 1.2 m/s) and six sliding distances (500, 1000, 2000, 3000, 4000 and 5000 m) were selected. The results show that wear rate depends on both sliding velocity and sliding distance. The wear mechanisms detected were plowing, microcracking and microcutting (typical mechanisms of fatigue wear). These mechanisms evolve according to sliding velocity and sliding distance, highlighting a transition zone in which wear rate is reduced.


The main aim of this article deals with the wear behavior of mechanically alloyed 17-Cr oxide dispersion strengthened (ODS) Ferritic steel consolidated through Vacuum Hot Pressing (VHP) at temperature level of 1170 °C under pressure level of 60 MPa with 60 minutes as holding time and with rate of cooling of 50 ˚C /min and a vacuum level of 10-3 torr. The persuade of wear process parameters were investigated based on the load applied, sliding velocity and sliding distance at a temperature of 350°C on dry sliding track of 17-Cr Ferritic oxide dispersion strengthened steel (Fe-17Cr-0.35Y2O3 -1.5ZrO2 -4Al (%wt). Wear test was conducted in a dry atmosphere using a pinon-disc wear testing machine. Wear behavior of 17-Cr Ferritic ODS steel was analyzed by using Taguchi approach. To examine the process parameter during high temperature wear rate analysis of variance and signal to noise ratios were used. During the wear analysis sliding distance was found to be influential parameters of wear rate for 17-Cr Ferritic oxide dispersion strengthened steel succeeded by functional load and sliding velocity. The regression model was found to calculate the rate of wear for 17-Cr Ferritic oxide dispersion strengthened steel.


2013 ◽  
Vol 6 (2) ◽  
pp. 139-153
Author(s):  
Israa .A.K

This research is devoted to study the effect of addition of different weight percent from SiCp ( 2, 4, 6, 8 ) to Al– 4 Cu alloy which have been fabricated by liquid metallurgy method on the dry sliding wear behavior and mechanical properties. Wear characteristics of Al–SiC composites have been investigated under dry sliding conditions and compared with base alloy. Dry sliding wear tests have been carried out using pin-on-disk wear test under normal applied loads 5, 10, 15 and 20 N and at different sliding velocity of (2.7, 3.7, 4.7) m/sec. It was also observed that the wear rate varies linearly with increases normal applied load but lower in composites as compared to the base material. The wear mechanism appears to be oxidative for both Al – Cu alloy and composites under the given conditions of load and sliding velocity as indicated by optical microscopic of the worn surfaces. Further, it was found from the experimentation that the wear rate decreases linearly with increasing weight percent of silicon carbide. The best results have been obtained at 8 % wt SiC . We also observed that the yield strength, tensile strength increases with increasing wt% of SiC , but the ductility decreases.


Polymers ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1805
Author(s):  
Yu ◽  
Zhang ◽  
Tang ◽  
Gao

(1) In order to improve the properties of antifriction and wear resistance of polyimide (PI) composite under high temperature conditions, (2) 3-Aminopropyltriethoxysilane (APTES) and Lanthanum (La) salt modifications were employed to manufacture poly-p-phenylenebenzobisoxazole (PBO)/PI composites with different interface properties. The representative ambient temperatures of 130 and 260 °C were chosen to study the friction and wear behavior of composites with different interface properties. (3) Results revealed that while both modification methods can improve the chemical activity of the surface of PBO fibers, the La salt modification is more effective. The friction coefficient of all composites decreases with the increase of sliding velocity and load at two temperatures, and the specific wear rate is increases. Contrary to the situation in the 130 °C environment, the wear resistance of the unmodified composite in the 260 °C environment is greatly affected by the sliding velocity and load, while the modified composites are less affected. Under the same test parameters, the PBO–La/PI composite has the lowest specific wear rate and friction coefficient, and (4) La salt modification is a more effective approach to improve the properties of antifriction and wear resistance of PI composite than APTES modification in high ambient temperatures.


1985 ◽  
Vol 107 (4) ◽  
pp. 491-495 ◽  
Author(s):  
Y. C. Chiou ◽  
K. Kato ◽  
T. Kayaba

It is shown that the severe-mild wear transition and the wear rate of 0.45 percent carbon steel pair in dry friction is greatly influenced by the change of normal stiffness from 1 N/mm to 586000 N/mm in loading system. The wear rate increases with the increase of normal stiffness and the severe wear state is predominant under larger normal stiffness at low sliding velocity (0.25 m/s). However, the wear rate decreases with the increase of normal stiffness and the mild wear state is predominant under larger normal stiffness at high sliding velocity (1.57 m/s). This complicated wear behavior is explained by analyzing the effect of normal stiffness and normal load on wear rate-sliding velocity curve. It suggests that the increase of normal stiffness should physically mean the increase of normal load.


2017 ◽  
Vol 139 (6) ◽  
Author(s):  
R. Nithesh ◽  
N. Radhika ◽  
S. Shiam Sunder

The modern technology developments have seeded for the necessity of composite materials that are incorporated with high hardness, high tensile strength, and better wear properties. Cu–Sn–Ni alloy as well as the composites of varying weight percentage of Si3N4 (5, 10, and 15) are fabricated by liquid metallurgy technique. The alloy and composites are tested for their tensile strength and hardness on Universal Testing Machine and Vickers microhardness tester, respectively. Based on the tests, Cu–Sn–Ni/10 wt. % of Si3N4 is found to have optimum mechanical properties. The scuff type adhesive wear behavior is studied through pin-on-disk tribometer under dry sliding conditions for Cu–Sn–Ni/10 wt. % of Si3N4 composite. Taguchi's design of experiments technique based on L27 orthogonal array model is used for analyses of process parameters in three levels such as applied load (10, 20, and 30 N), sliding distance (500, 1000, and 1500 m), and sliding velocity (1, 2, and 3 m/s). The parameters are ranked based on the signal-to-noise ratio and the analysis of variance approach. Based on wear results, applied load is found to have highest stature on influencing wear rate followed by sliding distance and sliding velocity. A generalized wear rate equation is obtained based on the linear regression model and its feasibility is checked. Scanning electron microscope (SEM) analyses revealed severe delamination occurred on maximum load condition. The development of this copper composite can have the possibility of replacing aluminum bearings.


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