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This study investigates the impact of wetting between fly ash and aluminum alloy on the wear resistance of composites. The research analyzes the chemical reactions, composite formation process, wear behavior, and influence factors affecting the properties of the composites. By optimizing the wetting evaluation and pre-treatment of fly ash, the study aims to enhance the wear resistance of the composites for potential industrial applications.
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Study the Effect of Wetting between Fly Ash – Aluminum Alloy on Wear Resistance of Composites Presenter:Liang Ging. Fan Author:Shueiwan H. Juang, Liang Ging. Fan,Shao Jun. Gu
Fly Ash ASTM C618、CNS 3036
Aluminum—Fly Ash, ALFA • JIS designation, ADC12, was selected as the base metal. Chemical composition of ADC12 Al alloy (wt% ) • Fly ash was gotten from Mailiao power plant (Taiwan) and its density is ranged about 2.0~2.5 (g/cm3). Chemical composition of fly ash(wt%)
SEM — Micrographs of Fly ash (a) (b) SEM micrograph showing (a) a complete particle of fly ash and (b) rough surface appeared on some particles.
Wetting porosity liquid solid fly ash SC:Spreading Coefficient γ:Interfacial Energy Θ:contact angle Al matrix SEM micrograph of ALFA composite.
Start Pre-treatment of fly ash Matrix metal Mixing with stirring Gravity casting Wetting evaluation no yes Property Measurement of composite castings End Experimental Procedure
Influence Factors of Fly Ash on Process • Particle characteristics Density, size, shape and volume fraction • Etch cleaning Remove the adsorbed contaminants • Pre-heated Degas, de-moisture clean fly ash. untreated
fly ash cluster Al matrix Al-Si Si Optical Micrographs of FalseALFA
Experiment Design • Matrix: Aluminum alloys, ADC 12 • Addition: 3wt% Mg into the liquid metal to reduce the surface tension. • Fly ash being pickled by sulfuric acid and pre-heated at 700 ℃ for a specified period, added into the aluminum melt at 850 ℃ with different weight percentage, such as 0wt%, 2wt%, 4wt%, 6wt%, 8wt% and 10wt%, and followed by mechanical stirring with 500 rpm to obtain a well-mixed melt.
Optical Micrographs of Accepted ALFA (a) (b) Micrograph of ALFA composites formed by gravity casting: (a) a complete particle and (b) uniform distribution of fly ash particles.
Density Measurements ADC12:2.68 g/cm3
Wear Tests • Wear behavior of ALFA composites tested using Pin-On-Disc apparatus under a load of 9.8N and 18.6Nat a constant sliding velocity of 0.5 m/s and sliding distance is 50 m. • Counterpart material used in the wear tests was Cr steel ball with ¼in. in diameter and HRC 58 in hardness. abrasion tester
Wear Tests Load:9.8 N Load:18.6 N
Conclusions • The test results revealed that the density of composites was decreased with increasing fly ash percentage. • Wear resistance of composites was improved as increasing fly ash percentage. • Pretreatment of fly ash is the key to obtain a successful ALFA composite. • In future, the die casting process will be introduced by virtue of runner passive stirring (RPS) to obtain a uniform distribution of fly ash inside metal matrix and a better structure by casting pressure.