Abstract: Technological advancements in the development of cutting tools and coolant/lubricant chemistry have enhanced the machining capabilities of hard materials under higher machining conditions. Generation of high temperatures at the cutting zone during machining is one of the most important and pertinent problems which adversely affect the tool life and surface finish of the machined components. Generally, cutting fluids and solid lubricants are used to overcome the problem of heat generation, which is not effectively addressing the problems. With technological advancements in the field of tribology, nano-level particulate solid lubricants are being used nowadays in machining operations, especially in the areas of turning and grinding. The present investigation analyses the effect of using nano-particulate graphite powder as lubricant in the turning of AISI 1040 steel under variable machining conditions and to study its effect on cutting forces, tool temperature and surface roughness of the machined component. Experiments revealed that the increase in cutting forces and tool temperature resulting in the decrease of surface quality with the decrease in the size of nano-particulate graphite powder as lubricant.
Abstract: The first laboratory synthesis of hard materials such as
diamond proceeded to attack of developing materials with high
hardness to compete diamond. Boron rich solids are good candidates
owing to their short interatomic bond lengths and strong covalent
character. Boron containing hard material was synthesized by modifiedmicrowave
method under nitrogen atmosphere by using a fuel
(glycine or urea), amorphous boron and/or boric acid in appropriate
molar ratio. Characterizations were done by x-ray diffraction (XRD),
Fourier transform infrared (FTIR) spectroscopy, scanning electron
microscopy/energy dispersive analyze (SEM/EDS), thermo
gravimetric/differential thermal analysis (TG/DTA).
Abstract: Cemented carbides, owing to their excellent
mechanical properties, have been of immense interest in the field of
hard materials for the past few decades. A number of processing
techniques have been developed to obtain high quality carbide tools,
with a wide range of grain size depending on the application and
requirements. Microwave sintering is one of the heating processes,
which has been used to prepare a wide range of materials including
ceramics. A deep understanding of microwave sintering and its
contribution towards control of grain growth and on deformation of
the resulting carbide materials requires further studies and attention.
In addition, the effect of binder materials and their behavior during
microwave sintering is another area that requires clear understanding.
This review aims to focus on microwave sintering, providing
information of how the process works and what type of materials it is
best suited for. In addition, a closer look at some microwave sintered
Tungsten Carbide-Cobalt samples will be taken and discussed,
highlighting some of the key issues and challenges faced in this
research area.
Abstract: Machining of hard materials is a recent technology for
direct production of work-pieces. The primary challenge in
machining these materials is selection of cutting tool inserts which
facilitates an extended tool life and high-precision machining of the
component. These materials are widely for making precision parts for
the aerospace industry. Nickel-based alloys are typically used in
extreme environment applications where a combination of strength,
corrosion resistance and oxidation resistance material characteristics
are required. The present paper reports the theoretical and
experimental investigations carried out to understand the influence of
machining parameters on the response parameters. Considering the
basic machining parameters (speed, feed and depth of cut) a study has
been conducted to observe their influence on material removal rate,
surface roughness, cutting forces and corresponding tool wear.
Experiments are designed and conducted with the help of Central
Composite Rotatable Design technique. The results reveals that for a
given range of process parameters, material removal rate is favorable
for higher depths of cut and low feed rate for cutting forces. Low feed
rates and high values of rotational speeds are suitable for better finish
and higher tool life.
Abstract: Within the framework of the FP7 project "START" the cooperation with European research centres has had a positive impact on raising the level of innovation researches and the introduction of innovations Institute for Superhard Materials of the National Academy of Sciences (ISM NAS) of Ukraine in the economy of Europe and Ukraine, which in turn permits to speeds up the way for Ukrainian science to the European research area through the creation in Ukraine the scientific organizations of innovative type.