Ultra-Mild Wear of Al2O3 Fibre and Particle Reinforced Magnesium Matrix Composites

2012 ◽  
Vol 445 ◽  
pp. 503-508 ◽  
Author(s):  
A. Banerji ◽  
Henry Hu ◽  
A.T. Alpas

Sliding wear behaviour of Mg alloy AM60 reinforced with Al2O3 fibers and particles, i.e, AM60-9% (Al2O3)f and AM60-(9% (Al2O3)f + 4% (Al2O3)p) have been studied by performing boundary lubricated pin on disk tests against AISI 52100 steel counterface under low loads (1.0-5.0 N). The results showed that the material loss from Mg composites tested under 1.0 N and 2.0 N loads was negligible. Under 5.0 N load and after 1.0×105 sliding cycles, AM60-9% (Al2O3)f showed increased volumetric loss whereas under the same conditions AM60-(9% (Al2O3)f + 4% (Al2O3)p) continued to protect the Mg-matrix from damage by the counterface as Al2O3 fibre+particle height remained exposed over the Mg matrix by 1.8 μm and acted as load bearing elements. Transfer of Fe particles to the worn surface of Mg composites resulting from extensive counterface damage due to abrasion by hard Al2O3 fibres and particles was also detected.

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.


2018 ◽  
Vol 140 (3) ◽  
Author(s):  
Hui Tan ◽  
Jun Cheng ◽  
Shuai Wang ◽  
Shengyu Zhu ◽  
Yuan Yu ◽  
...  

Wear-resistant aluminum alloys have enormous potential applications. In this paper, the Al–20Si–5Fe–2Ni alloy was fabricated by hot-pressed sintering, and its dry sliding wear behavior was investigated from 25 °C to 500 °C sliding against Al2O3 ceramic and AISI 52100 steel. The microstructure, phase, high temperature hardness, and worn surface of the sintered alloy were examined. The results indicate that the uniform distribution of Si particles and Al5FeSi intermetallic in the Al matrix contribute to its superior tribological properties. Additionally, the correlation of the tribological behavior of the alloy with the sliding testing conditions was studied, and its wear mechanism was discussed.


2007 ◽  
Vol 280-283 ◽  
pp. 1327-1330
Author(s):  
Chien Cheng Liu ◽  
Jow Lay Huang

The effects of TiN addition to Si3N4 on its mechanical and wear properties were investigated. The size and content of TiN particles were found having effects on the strength and toughness of Si3N4-based composites. The friction and wear behavior of Si3N4 based composites against AISI-52100 steel were investigated in the ball -on- disc mode in a non-lubrication reciprocation motion. It has been found that under the conditions used all the ceramic components exhibited rather low friction and wear coefficients. For monolithic silicon nitride materials, high friction coefficients between 0.6 and 0.7 and wear coefficients between 1.63 × 10-8 and 1.389 × 10-6 mm3/N.m were measured. The contact load was varied from 100 to 300 N. By adding titanium nitride, the friction coefficients was reduced to a value between 0.4 and 0.5 and wear coefficients between 1.09×10-8 and 0.32×10-6 mm3/N.m at room temperature.


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