Wear Properties of Al-17Si Alloys with Variable Fe Levels Formed by Semi-Solid Process

2014 ◽  
Vol 217-218 ◽  
pp. 111-118
Author(s):  
Shu Sen Wu ◽  
Chong Lin ◽  
Shu Lin Lü ◽  
Ping An

The Fe-rich Al-Si alloys have the potential to be used to make wear-resistant parts. However, there has been few work devoted to study the wear behavior of the hypereutectic Al-Si alloys with about 2% Fe (mass %). In this work, the semi-solid slurry of the alloy was prepared by an ultrasonic vibration (USV) process. The effect of Fe content on dry sliding wear properties of the alloys rheo-casted after USV treatment was investigated. The wear tests were carried out using a pin-on-disc wear tester at four different loads of 50N, 100N, 150N and 200N at a constant sliding speed of 0.75m/s. The results show that the wear rate of USV treated alloy increases almost linearly as the applied load increases from 50 N to 200N. The alloys made with semi-solid process exhibited improved wear resistance at the entire applied load range in comparison to the conventional casting alloys. At the applied load of 50N, oxidative wear is the dominant mechanism for the alloys with USV treatment. At 200N, a combination of delamination and oxidation wear is the main wear mechanism. The wear resistance of Al-17Si alloys containing 2% to 3% Fe is closely related to the morphology, size and volume fraction of Fe-bearing compounds, which can be changed by USV semi-solid process.

2021 ◽  
Vol 118 (6) ◽  
pp. 614
Author(s):  
Chellamuthu Ramesh Kumar ◽  
Subramanian Baskar ◽  
Ganesan Ramesh ◽  
Pathinettampadian Gurusamy ◽  
Thirupathy Maridurai

In this research, investigations were carried out on Al6061 base alloy with the changing weight percentage of silicon carbide (SiC) and boron carbide (B4C) with keeping the amount of talc constant. The main objective of this present study was to improve the wear resistance of aluminum alloy using SiC/B4C/talc ceramic particles using stir-casting technique and how the eco-friendly talc content influencing the solid lubricity during the abrasion process. The experiments were conducted via orthogonal array of L27 using Taguchi’s method. The optimum value along with the coefficient of friction was obtained on the basis of grey relational equations and ANOVA, which helped in analysis of most influential input parameters such as applied load, sliding speed, sliding distance and percentage of reinforcement. Conformation tests were performed for the purpose of validation of the experimental results. The specimens were analyzed using scanning electron microscope (SEM) with EDX for micro structural studies. The SiC, B4C and talc presence in the composite helped to improve the mechanical properties, according to the results. The presence of solid lubricant talc as reinforcement to the aluminum hybrid composite reduced the wear properties and decreased the co-efficient friction. These wear resistance improved aluminum metal matrix composites could be used in automobile, defense and domestic applications where high strength and wear resistance required with lesser specific weight.


2017 ◽  
Vol 13 (3) ◽  
pp. 32-36
Author(s):  
S. Rajesh ◽  
C. Velmurugan

Metal matrix composite (MMC) focuses primarily on improved specific strength, high temperature and wear resistance application. Aluminum matrix reinforced with titanium carbide and molybdenum disulfide has good potential and also self-lubrication. The main challenge is to produce this composite in a cost effective way to meet the above requirements. In this study Al–TiC-MoS2 castings with different volume fraction of TiC and MoS2 were produced in an argon atmosphere by an enhanced stir casting method. Hardness of the composite has increased with higher % of TiC addition. At that same time self-lubrication of composite has occur in the effort of MoS2. Dry sliding wear behavior of AMC was analyses with the help of a pin on disc wear and friction monitor. The present analyses reveal the improved hardness  as well as wear resistance.


2010 ◽  
Vol 7 (1) ◽  
pp. 1 ◽  
Author(s):  
Muna K. Abbass

 The aim of the present research is to study the effect of cadmium addition on microstructure and wear behavior of the alloy (Al-12%Si) under dry sliding conditions. Wear behavior was studied by using the Pin-On- Disc technique under different conditions at applied loads 5-20 N, at constant sliding speed and in constant time. The steel disc hardness was 35HRc. All alloys were prepared with different percentages of cadmium (1.0, 2.0, 3.0) wt%. Also the base alloy was prepared by melting and pouring the molten metal in a metallic mold. It was found that the cadmium addition to Al-Si matrix decreases the wear rate and improves the wear properties for alloys containing -Cd under loads above 10N. It was also found that the alloy Al-12%Si containing 3%Cd is the best alloy in wear resistance and friction coefficient. This is due to presence of the Cd-phase as cuboids or hard particles distributed in a eutectic matrix which reduces the friction coefficient at high loads (20N). 


2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
B. R. Senthil Kumar ◽  
M. Thiagarajan ◽  
K. Chandrasekaran

This work has investigated to find the influence of silicate on the wear behavior of LM 24/4 wt.% fly ash hybrid composite. The investigation reveals the effectiveness of incorporation of silicate in the composite for gaining wear reduction. Silicate particles with fly ash materials were incorporated into aluminum alloy matrix to accomplish reduction in wear resistance and improve the mechanical properties. The LM24/silicate/fly ash hybrid composite was prepared with 4 wt.% fly ash particles with 4, 8, 12, 16, 20, and 24 wt.% of silicate using vortex technique. Tribological properties were evaluated under different load (15, 30, 45, 60, and 75 N); sliding velocity (0.75, 1.5, 2.25, and 3 m/sec) condition using pin on disc apparatus and mechanical properties like density, hardness, impact strength, and tensile strength of composites were investigated. In addition, the machining of the aluminum hybrid composite was studied using Taguchi L9orthogonal array with analysis of variance. The properties of the hybrid composites containing 24 wt.% silicates exhibit the superior wear resistance and mechanical properties.


2014 ◽  
Vol 592-594 ◽  
pp. 1357-1361 ◽  
Author(s):  
M. Ramesh ◽  
T. Karthikeyan ◽  
A. Kumaravel ◽  
C. Kumaari

The wear behavior of aluminium alloy (A356) reinforced with 5 wt. % of quarry dust particles composite disc was sliding against automobile brake friction lining pin was investigated. Dry sliding wear studies were investigated in pin-on-disc apparatus. The wear tests were carried out range of applied load 20 to 60 N and constant sliding velocity (0.5 m/s) under sliding distance of 500 m. The wear behavior of aluminium metal matrix composite (AMC) has been compared with the commercially used 25 grade Gray Cast Iron disc (GCI).The results showed that the wear rate of AMC disc decreased with increasing the applied load. However the wear rate of AMC disc with respective pin decreased with increasing the applied load. The coefficient friction increased with increasing the applied load. The scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDAX) used to investigate the disc and pin. The wear debris was analyzed by SEM image.


Metals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 596 ◽  
Author(s):  
Xiaobo Liu ◽  
Miao Yang ◽  
Dekun Zhou ◽  
Yuguang Zhao

In situ Mg2Si–Al composites were prepared by using gravity casting and semi-solid extrusion. After P modification, the primary Mg2Si transformed to polygonal blocks. Extraction tests showed that the Mg2Si crystals had octahedral and tetrakaidekahedral morphologies. The semi-solid microstructure of the double-spheroidized α-Al matrix and reinforced-phase Mg2Si was successfully obtained by using semi-solid extrusion. Extraction tests showed that the Mg2Si crystals had a spherical morphology. Dry sliding wear behaviors of in situ Mg2Si–Al composites fabricated by using gravity casting and semi-solid extrusion with isothermal heat treatment holding times of 50, 60, and 160 min against 45 steel, under conditions of different sliding speeds and loads, were investigated. The worn surfaces were analyzed using SEM and EDS techniques. The results showed that Mg2Si–Al composites fabricated by using semi-solid extrusion were superior in terms of wear resistance to Mg2Si–Al composites fabricated by using gravity casting, because the former had uniformly distributed spherical reinforced phase particles of Mg2Si with weaker stress concentration around the particles, delaying the generation and expansion of cracks. The Mg2Si particles were not easily detached from the matrix, and once they fell off, the Mg2Si particles only served as spherical abrasive grains, with relatively small cutting and wear properties for the composite material. It was found that the Mg2Si/Al composite fabricated by using semi-solid extrusion with an isothermal heat treatment holding time of 60 min had the best wear resistance. The failure mechanisms of Mg2Si/Al composites were found to be mainly adhesive wear and abrasive wear.


2018 ◽  
Vol 7 (2.23) ◽  
pp. 87
Author(s):  
Dileep Divakaran Namboodiri ◽  
S Ilangovan

The present work deal with an investigation of the mechanical and wear properties of eutectic Al-12.8%Si-2.5%Cu under as cast and homogenized conditions. The alloy was melted in a ceramic crucible, stirred and gravity poured into a metal mold and was then cooled under atmosphere. The stirring parameters include a stirrer speed of 400rpm at a melt temperature of 7500C for about 10 minutes. The cast specimens were homogenized in a nitrogen atmosphere crucible at a temperature of 3500C for 8 hours and furnace cooled to room temperature. The microstructure of as cast and homogenized specimen were studied under SEM. The results of SEM study showed that the Si particles were more evenly dispersed around the a-Al matrix after homogenization. This even dispersion of Si particles led to an increase in the hardness and ultimate tensile strength of the alloy. The dry sliding wear behavior was studied using a pin-on-disc machine. It is seen that the wear rate reduced with increase in sliding speed. The EDAX analysis of worn surface showed the phenomenon of lamination. It is concluded that the oxide layer formation was also a reason for increase in wear resistance of the material.  


2015 ◽  
Vol 1104 ◽  
pp. 155-161 ◽  
Author(s):  
El Oualid Mokhnache ◽  
Gui Song Wang ◽  
Lin Geng

The dry sliding characteristics of three in situ Al2O3/Al-Si composites fabricated with volume fraction of 10, 20 and 30 vol.% were investigated. The effect of sliding parameters on the wear properties was investigated. As the sliding velocity increases the wear loss decreases systematically. When the volume fraction increased to 20 vol.%, an improvement of wear resistance was obtained. However, when the volume fraction was 30 vol.%, a further decrease of wear resistance was observed. In case of low volume fraction (10 vol.%), an extensive plastic deformation by plowing out the ductile Al matrix along with narrow grooves was observed. As the volume fraction increased to 20 vol.%, the abrasive wear by micro grooving is dominant as well as the low load is used. Whereas, when the volume fraction increased to 30 vol.%, besides the effect of large pores, the embedded Al2O3 in the massive Si blocks formed a weaker interface thereby behaving as source of crakes initiation and propagation. As result, fracture, micro-cutting and delaminating are observed as dominant abrasive wear mechanisms


Author(s):  
I. Ovali ◽  
H. Karakoç ◽  
H. Çinici

Purpose: In the present study, the effects of B4C reinforcement volume fraction (% 5-15-20)on the abrasive wear properties of AA2024 matrix composites produced with hot pressingmethods were investigated.Design/methodology/approach: As-received samples were also used for comparison.AA 2024 powder was mixed with B4C-SiC-Al2O3 particles by a three dimensional mechanicmixer for 30 minutes. Mixed powder was pressed under 60 MPa at room temperature in thesteel mold by unidirectional. Steel mold kept in the furnace at 550ºC after the pre-pressingfor 30 minutes. Samples were pressed in heated mold under 100 Pa. The wear tests werecarried out using a pin-on-disk wear tester by sliding at sliding speeds of 1.2 m/s againstsilicon carbide paper. Normal loads of 10, 20 and 30 N at constant sliding speed at roomtemperature.Findings: The experimental result showed that B4C volume fraction significantly influencethe wear behavior of AA2024 matrix composites produced with hot pressing methods.Originality/value: It was also found that the wear resistance of AA2024 matrix compositesproduced with hot pressing methods increases with increasing B4C volume fraction.The highest weight loss was obtained in the unreinforced matrix material.


Metals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1663
Author(s):  
Fei Chen ◽  
Binbin Wang ◽  
Zhiqiang Cao

In situ ZA27/TiB2 composites were synthesized successfully by diluting the in situ Al/TiB2 composite, which was used as a master alloy. The microstructure and hardness of the developed in situ composites have been investigated. Results have shown that TiB2 particles distribute uniformly through the matrix and significantly refine the matrix grain. The hardness of the composites was higher than that of the matrix alloy and increased with the increasing TiB2 content. The dry sliding wear behavior under heavy loads and high rotation speed were studied in detail by using a pin-on-disc wear tester at room temperature. The results revealed that the wear resistance of the composites increased monotonically with the increase in the TiB2 content. The composites had a lower coefficient of friction, friction temperature, wear rate, and specific wear rate especially under high loads when compared with the matrix alloy. An increase in the applied load increased the wear severity by changing the wear mechanism from abrasion and oxidation to adhesive wear. The composites possess better adhesive wear resistance properties compared with the matrix, which shows obvious adhesive wear as the load increased to 36 N, while the ZA27/3.0% TiB2 composite did not show adhesive wear until the load increased to 54 N.


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