BazTech - Yadda

1

Microstructure, wear and mechanical properties of plasma sprayed TiO2 coating on Al–SiC metal matrix composite

Dinesh Babu P., Prasannakumar B., Marimuthu P., Mishra R. K., Ram Prabhu T.

Archives of Civil and Mechanical Engineering

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2019

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Vol. 19, no. 3

756--767

EN

In the present study, the hard TiO2 coating was plasma sprayed on the Al/SiC composite substrate. The coating was characterised for microstructure, mechanical and tribological properties and compared with the substrate. The key findings from the present study are: (1) The lamellae structure of the coating contains semi and fully melted particles, round porosity without any evidence of spallation or delamination or un-melted particles and non-stoichiometric and oxygen deficient phases and shorter stand-off distance would be a probable reason for the occurrence of partial melted regions and porosity in the coating, (2) The coating has improved significantly scratch resistance, hardness, fracture roughness, friction coefficient and wear resistance of the substrate, and (3) mild abrasive wear is responsible for low wear loss in the coated sample whereas the combination of severe delamination wear and abrasive wear causes the considerable wear loss in the uncoated sample.

2

Influence of Milling Time on the Crystallite Size of AlSi5Cu2/SiC Composite Powder

Suśniak M., Pałka P., Karwan-Baczewska J.

Archives of Metallurgy and Materials

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2016

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Vol. 61, iss. 2B

977--980

EN

AlSi5Cu2/SiC nanocrystalline composite powder was successfully obtained by mechanical alloying of AlSi5Cu2 chips with reinforcement of 0, 10, 15, 20 wt. % of silicon carbide. X-ray powder diffraction was used to characterize obtained material. Detailed analyses using transmission and scanning electron microscopy have been conducted in order to collaborate the grain size measurement determined from the XRD analyses. Powders produced in a planetary ball mill with milling time: 1, 5, 10, 15, 20 and 40 hours, have shown shape and size evaluation during mechanical alloying process. It can be seen tendency to decrease the size of the grain as the milling time is increased. It is also noted that the grains of composites (AlSi5Cu2/SiC) are smaller than samples prepares without SiC addition. 40 hours of milling lead to formed very small grains of Al phase (20 nm in average) in composite powder.

3

An Experimental Study Of Aluminum Alloy Matrix Composite Reinforced SiC Made By Hot Pressing Method

Suśniak M., Karwan-Baczewska J., Dutkiewicz J., Actis Grande M., Rosso M.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 2B

1523--1527

EN

The present work investigates the possibility of using powder metallurgy processing for producing a metal matrix composite. Materials were prepared from AlSi5Cu2 chips with reinforcement of 10, 15, 20 wt. % silicon carbide. Aluminum alloy chips were milled with SiC powder in a high-energy ball mill by 40 hours. Mechanical alloying process lead to obtain an uniform distribution of hard SiC particles in the metallic matrix and refine the grain size. The consolidation of composite powders was performed by vacuum hot pressing at 450°C, under pressure of 600 MPa by 10 min. The results shows that the addition of SiC particles has a substantial influence on the microstructure and mechanical properties of composite powder as well as consolidated material. Hot pressing is an effective consolidation method which leads to obtain dense AlSi5Cu2/SiC composite with homogeneous structure and advanced mechanical properties.