Performance of uncoated WC-Co in end milling of Aluminium Silicon Carbide (AlSiC)
Metal matrix composite (MMC) with silicon carbide (SiC) reinforcement in pure aluminum matrix have found wide application in the automotive industry, especially in fiber reinforced pistons and particle-strengthened brake discs. Silicon carbide (SiC) reinforcement provides improved mechanical prop...
| Main Authors: | , , |
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| Format: | Book Chapter |
| Language: | English |
| Published: |
IIUM Press
2011
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| Subjects: | |
| Online Access: | http://irep.iium.edu.my/23612/ http://irep.iium.edu.my/23612/ http://irep.iium.edu.my/23612/1/Chapter_33.pdf |
| Summary: | Metal matrix composite (MMC) with silicon carbide (SiC) reinforcement in pure aluminum matrix
have found wide application in the automotive industry, especially in fiber reinforced pistons and
particle-strengthened brake discs. Silicon carbide (SiC) reinforcement provides improved
mechanical properties, thermal stability, high temperature formability and workability. However, the
presence of the SiC phase in the structure causes serious machinability problems, especially when
uncoated and coated WC-Co tools are used for their machining. High intensity of wear is attributed
to high abrasive wear caused by the hard silicon carbide particles. In the current work investigations
have been conducted to compare the performance of Poly Crystalline Cubic Diamond (PCD) tools
with the conventional uncoated tungsten carbide-cobalt tool in machining aluminum silicon carbide
(AlSiC) in terms of the applicable cutting speed ranges; chip morphology, tool wear rates and tool
wear morphology, volume of metal removal allowed per tool life and attainable surface
roughness.Most of the attentions are on those based on aluminum alloys and reinforced with silicon
carbide [1]. AlSiC is preferred over ceramics because of the useful combination of properties such
as high strength, ductility and high temperature resistance, whereas ceramics though are stiff and
strong but are brittle in nature [2]. Li et al [3] found that aluminum alloys reinforced with silicon
carbide particles are as much as three times more efficient than the un-reinforced aluminum alloys in
defeating tungsten projectiles at 1.2 km/sec. In automobile industry, AlSiC has been considered for
use in automobile brake discs and various components in internal combustion engines. Aluminum
silicon carbide (AlSiC) is being widely used not only in aerospace and automobile industries, but
also in the electronic industry, because of its unique thermal properties that are ideally suited for all
electronic packaging applications. Though the list of favorable attributes for this new engineering
material is quite impressive, the machinability of AlSiC is very poor because of the high tool wear
rates associated with abrasive wear, which make it a class of difficult-to-machine advanced
materials [4]. The silicon carbide phase, which has hardness in the range of tungsten carbide (WC),is mainly responsible for the high abrasive wear of the tool. Consequently the cutting edge of the
tool which in course due to abrasion wear results in the formation of poor surface finish during
turning [5]. During to the cutting tool edge [6]. In this process more particles join in with those
already adhering AlSiC machining, under high temperature and pressure the particles of AlSiC
adhere to form the so-called built
during turning [7]. |
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