Effect of compaction pressure on microstructure, density and hardness of Copper prepared by Powder Metallurgy route

Cenospheres are very cheap, and are reasonably strong and thermally stable upto 1200°C. In view of this attempt has been made to use these cenosphere for making Titanium syntactic foams with varying relative densities. Precautions were taken for selecting cold compaction pressure to minimize cenosphere crushing. The sintered samples were then characterized in terms of microstructures primarily to see the extent of cenosphere crushing, distribution of cenosphere, and extent of sintering. The foams made using optimized pressure and sintering parameters, exhibits uniform distribution of cenosphere without any significant crushing. The plateau stress, energy absorption and modulus of these foams are varying with the cenosphere content or the relative density, and these parameters can be engineered by varying cenosphere content in the foam. These foams exhibit considerably higher strength and stiffness than the conventional foam and show the possibility of using them for biomedical and engineering applications.

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Optimization of Warm Compaction Process Parameters in Synthesizing Carbon-Copper Composite Using Taguchi Method

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.701.112 ◽

2016 ◽

Vol 701 ◽

pp. 112-116

Author(s):

Salina Budin ◽

Mohd Afiq Nurul Hadi ◽

Talib Ria Jaafar ◽

Mohd Asri Selamat

Keyword(s):

Powder Metallurgy ◽

Taguchi Method ◽

Rupture Strength ◽

Compaction Pressure ◽

Compaction Process ◽

Compaction Temperature ◽

Warm Compaction ◽

Copper Composite ◽

Best Parameters ◽

Powder Metallurgy Route

Carbon–copper composites are attractive materials used for electrical applications, such as brushes for engines and generators, slip rings, switches, relays, lugs, contactor and current collector. Various methods can be used to prepare Carbon-copper composite, such as infiltration, sintering, cold pressing, hot pressing or isostatic pressing. However, powder metallurgy route is seen to be most favorable due to its possibility of producing uniform microstructure and excellent net shape product. In this work, carbon-copper composite is prepared using powder metallurgy route with warm compaction process. The compaction pressure (A), compaction temperature (B), post baking temperature (C) and compaction time (D) were optimized by Taguchi method. Hardness and transverse rupture strength (TRS) were used to assess the effect of warm compaction process. The experimental design is according to the L9 (34) orthogonal array. Signal to noise and analysis of variance (ANOVA) are employed to analyze the effect of warm compaction parameters. It is found that the best parameters and their levels are A3B2C3D2 for the main effect of hardness and the best parameters and their levels for TRS is A3B2C3D1. It is also notified that optimized parameters of A3, B2 and C3 are identical for hardness and TRS. However, for parameter D, the best level for hardness is D2 and for TRS is D1. The ANOVA analysis proved that compaction temperature parameter is significant to hardness and TRS value whereas the others parameters are not significant.

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Compaction Optimization of Sn-Cu-Si3N4 via Powder Metallurgy Route for Composite Solder Fabrication

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.421.267 ◽

2013 ◽

Vol 421 ◽

pp. 267-271

Author(s):

Muhammad Hafiz Zan Hazizi ◽

M.A.A. Mohd Salleh ◽

Zainal Ariffin Ahmad ◽

A.M. Mustafa Al Bakri ◽

A. Abdullah ◽

...

Keyword(s):

Powder Metallurgy ◽

Mechanical Alloying ◽

Composite Solder ◽

Compaction Pressure ◽

Compaction Process ◽

Thin Disc ◽

Best Parameter ◽

Porosity Percentage ◽

Powder Metallurgy Route

The aim of this study was to optimize the compaction process of a composite solder fabricated via powder metallurgy route, before details study were conducted in the next stage. Powder of Sn, Cu and Si3N4 were carefully weighted, mixed and blended in a mechanical alloying machine. Si3N4 were added to the Sn-0.7Cu solder as reinforcement.After 6 hours of mixing and blending, the powders were later compacted into a thin disc at 5 different pressures. Densities and volumes of the compacted samples were then obtained by using MicromeriticsAccuPyc II 1340 Gas Pycnometer. All data were analyzed and compared with each other in order to select the best parameter for compaction pressure. Results showed that at 140 bars, the porosity percentage is the lowest. Hence, it was decided that 140 bars is the best parameter for compaction process.

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