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India 2,3,4Department of Mechanical Engineering, Osmania University, Hyderabad, A.P.
The very nature of spark erosion or EDM requires the material to be electrically conductive, a property all the ceramics do not possess.
Here Al-alloy, Silicon carbide composite has been machined to analyze the effect of grain size of SiC and its percentage (which affects the electrical conductivity) on the machining rate.
The two factors affecting the erosion rate in EDM of MMC components are the concentration and size of ceramic particulates.

These materials have special properties and usage.
The alloy properties could be influenced by this phenomenon extensively.
The electromagnetic simulated microgravity is to place metal melt in electromagnetic fields which are perpendicular to each other, and electromagnetic volume force excited from the liquid will have effect on every volume unit of materials which could compensate the gravity and reduce  segregation and weight loss of lithium during alloy smelting. [16] In the aluminium-lithium alloy, the lithium content directly affects the mechanical properties of the alloy.
The consumption of lithium in smelting process is mainly affected by the following two factors: (1) Interaction between lithium and crucible.
The mechanical properties such as fracture toughness and elastic modulus have been improved by reducing the weight of aluminium-lithium alloy.

Additional important factor was that the material was cut without application of a coolant.
In the Table 2 the most important mechanical parameters of materials are tabulated.
a) ERTHALON 6 PLA (PA 6G): cast material, white colour, wear resistant, good machining properties, thermal ageing resistant, ,cross section homogenous structure retrieve during crosslinking process in form, similar parameter as ERTHALON 66 SA commonly applied for turning in lathe machines, b) ERTHALON LFX (PA6 + oil): cast material, green colour, capable of self-lubricity, reduced friction factor, thermal ageing resistant, wear resistance is ten times higher than ERTHALON 6 PLA, cross section homogenous structure retrieve during crosslinking process in form, c) NYLATRON GSM IPA 6 (MoS2 additive): cast material, grey-black colour, good machining properties, thermal ageing resistant, dense crystalline structure, cross section homogenous structure retrieve during crosslinking in form.
Additional factor that has an influence on a turning process is chips stiffness.
The oil high temperature circumstances affect the polyamide and surface peels itself during turning process.

Introduction Carbon control during sintering is a critical issue in order to reach the desired mechanical properties of a sintered product.
Another chemical reaction CO + H2 ⇔ C + H2O is also affecting the carbon level and it is therefore important to also measure the water content.
Important factors to study were: The measured and thermodynamically calculated CO2 and H2O levels in the sintering cycle.

The elimination of the subsequent thermal treatment at elevated temperatures avoids not only the damage of mechanical properties of the cpTi substrates, but also the loss of Ti-OH functional groups that play key role in apatite nucleation.
At the present stage, it is not easy to clarify the exact mechanism; however, one may suspect that the existence of Ta modifies the atom arrangements of the amorphous titania gel, thus affects readily the subsequent crystallization process, as suggested by Petkov et al. [4].
Although it is quite clear from the present experiment that Ta favors both the low-temperature crystallization and the formation of rutile, the low-temperature crystallization process is very complicated and is affected readily by other factors.

Manufacturers need to chose tools with the shape and geometry which are suitable to profile turning to ensure gouge-free cutting condition, delicate roughness, physico-mechanical properties of part surface, the rigidity of the technology system and the tool-life.
The main factor directly influence on the cutting process is the clearance angle that is measured in the normal section of the edge.
- Materials: SUS304 steel has chemical composition, mechanical properties according to JIS G-4303-91 standard
The result is consistent with the theory. 2) The processing surface roughness is significantly affected by the part profile.
Tuyen, “Theory of surface shaping and application in mechanical engineering”, Vietnam education Science and Technics Publishing House, Hanoi, 2013

Introduction The phenomenon of crystallization following after pouring molten metal into the mould, determines the shape of the primary casting (ingot) structure, which significantly affects on its usable properties.
Due to the small width of chilled crystals zone, the usable properties of casting (ingot) depend mainly on the width and length of the columnar crystals, the size of equiaxed crystals and content of theirs zone on section of ingot.
According to presented data in papers [3, 4], this type of structure gives low mechanical properties of castings and mainly is unfavourable for the plastic forming of continuous and semi-continuous ingots, because causing forces extrusion rate reduction and during the ingot rolling delamination of external layers can occur.
This structure can be eliminated by controlling the heat removal rate from the casting (ingot), realizing inoculation [3÷10], which consists in the introduction of additives to liquid metal and/or influence of external factors for example infra- and ultrasonic vibrations or electromagnetic field [4, 10÷14].
In case of this inoculation with use of external factor in form of electromagnetic stirring, which creates forced movement of liquid metal in mould in time of its solidification, the refinement of primary structure mainly results from thermal and mechanical erosion of crystallization front.

The study indicates that the size of the magnetic axis is the main factor affecting the attraction, but the shape parameters of the brake are the key affecting the magnetic field distribution.
The model includes the permanent magnets of brake and its coupled railway steel rail, and the brake device ignores non-critical parts (such as bolts) that do not affect the computational result[5].
The simulation has the following assumptions: (1) Influence of change of parameters on mechanical property is ignored; (2) All the simulation results are within acceptable scope.
During the process of braking, the partition board of certain width may effectively reduce leakage flux and thus increase permanent-magnetic attraction; however, when the width is relatively large, the volume of magnetic conducting material is affected and reduced, thus affecting conducting of magnetic force.
Proper wear may affect air gap distribution between the slipper and the steel rail, but has little influence on the permanent-magnetic attraction.

It is expected that with improvements in mechanical and tribological properties, hydrogels could be served as promising load-bearing biomaterials.
The covalent bonds between the hydrogel network and NPs is a key factor in fulfilment of load-transfer between two phases, leading to an increase in mechanical strength and toughness.
For instance, incorporation of silicon-based NPs in the biomaterial, would add the bioactive properties to it, as silicon is known to contribute significantly in osteogenic differentiation of stem cells, as well as encouraging collagen type I production [15].
A previous study showed the introduction of nano- particle hydroxyapatite into PEG matrix, improved the mechanical properties and structural stability to endure philological environment, in addition to an increase of cell adhesion [15].
In general, pitting was less occurred in NCHs compared to the reference hydrogel, thanks to the influence of Si-NP on mechanical property improvement of the matrix.

This area is affected significantly by typhoons.
It is always affected seriously by typhoons in summer and winter.
All these factors lead to the lack of uniform planning of navigational facilities on islands along the channel.
These factors make SCS become a high-risk area of accident, so SCS, especially in the areas around SCS islands, accidents are frequent.
[4] Shi Chun-lin, On the Present Main Factors to Affect Navigation Safety in SCS, the New Orient, No 2,2012,pp7～8