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Tungsten carbides are generally called as carbides. Cobalt with Tungsten carbide acts as a binder. When Cobalt added with other elements like Ni / Cr / Mo / Ti are called as cemented carbides.
Sintering is a thermal treatment given to these carbides so as to eleminate the porosities and densify them. During this treatment cobalt binds the WC particles and we get high density.
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What is the difference between calcination temperature and sintering temp?
calcination - basically is a single step heating process where it determines either further heat treatment (sintering) is necessary or not. For example, let say BaTiO3. the reaction between BaO and TiO3 definitely will produced BaTiO3 without having intermediate phase. Although, secondary phase might presence, however, it may decrease with increasing calcination temperature. By the way, if the intermediate phase is a must for next reaction, then calcination has to be followed by sintering process (to provoke further reaction). Sintering is well-known in whiteware as to produce solid body by particle diffusion. However, regards to the calcination process which is formation of intermediate reaction need to be undergo sintering process to ensure all those reaction occur in calcination process are completely reacted to form another a very stable phase.
How is uranium used in a mixture?
Uranium can be used in alloys, for example U-Zr-Er. Uranium can be used as mixed oxide, for example MOX = UO2 and PuO2. Uranium can be used also as mixture of carbides, molten salts mixture, solutions and suspensions, etc. but more rare.
What is a neodymium magnet made out of?
Neodymium NdFeB rare earth magnets are sintered by powder metallurgy with chemical composition of Nd, Fe, B and other minor elements. Neodymium Iron Boron (NdFeB) magnets are composed of Nd, Fe, B, Dy, Co and other minor elements. NdFeB neodymium magnets are the rare earth magnet with the highest magnetic performance and coercive force in the world.Production Process of Rare Earth Neodymium Magnets1. Vacuum MeltingCompositions of neodymium, iron , iron-boron, dysprosium and minor additions including cobalt , copper , gallium, aluminum and others are mixed and induce-melted to form Nd2Fe14B phase and other necessary structures required for high performance permanent magnets. The melting temperature reaches over 1300o C. Usually repeated melting is needed to be produce an even phase and structure distribution .2. CrushingThe ingots from vacuum melting process are crushed into coarse powder directly , or strip cast followed by HDDR processing into coarse powder .3. Jet MillingThe coarse powder further milled into required particles sized about 3 microns in diameter by a jet miller . Those particles become single-domain and anisotropic which are critical for producing a high coercivity magnet. Jet milling is the most effective way to mill the particles so far.4. PressingCompact the fined powder to re-produces block magnets. Usually a magnetic field is applied during pressing to align those anisotropic particles in order to produces maximum magnetic output in particular direction. There are two pressing methods, transverse and axial , depend on different application. Isostatic pressing is normally used to further densify magnets to 75-80% .5. Vacuum SinteringThe compacted magnets are sintered ate temperature above 1000 o C and for many hours to be solidifiedand compacted further more up to 99% by shrinking its body. A required microstructure between particles for high performance permanent magnets is also formed in this stage. Some following heat-treatments are needed to stabilize the magnets .6. MachiningShrinkage and distortion during sintering is too difficult to control adequately and magnets normally need at least a " clean up" grind on the surface. Small parts are cut or sliced precisely forma big block to meet the demanding tolerances and different shapes .7. Surface TreatmentVarious surface treatments can be applied on the final products . They include zinc, nickel ,Ni-Cu-Ni multi-layer, e-coating , epoxy and others. They provide different surface finishing, appearance and corrosion resistance, applicable in different application environments.
What has the author Marc R Freedman written?
Marc R. Freedman has written: 'Improved consolidation of silicon carbide' -- subject(s): Density measurement, Dies, Pressing (Forming), Silicon carbide, Silicon carbides, Sintering 'A sintering model for SiCw/SiN composites' -- subject(s): Sintering, Silicon nitride
What is the difference between sintering and annealing?
Annealing and Sintering are the same processes.
What is sintering point of compound NaCl?
The melting (not sintering) point of sodium chloride is 801 0C.
When was Ironton Sintering Plant Complex created?
Ironton Sintering Plant Complex was created in 1924.
Is sintering mandatory for powder metallurgy Why?
Sintering welds the metal powder grains together without melting them completely. This produces a solid but porous piece of metal.
Where can one obtain more information about Laser Sintering?
There are several websites where an individual can obtain more information about laser sintering. Examples would include Wikipedia and the Free Dictionary.
What is the method sintering used for?
Sintering is a method for creating objects from powders. It is based on atomic diffusion. Powder is heated to near it's melting point in a mold and then allowed to reform.
When carbon and uranium combine what do they make?
Uranium carbides as: UC, UC2, U2C3; uranium carbides are used as nuclear fuel and rarely as catalysts in chemical engineering.
What is meant by selective laser sintering?
Selective laser sintering is the process of using an additive in a manufacturing technique that uses an ultra high powered laser and is used for prototype models and functional components.
What has the author Udom Techakijkajorn written?
Udom Techakijkajorn has written: 'Sintering of fume deposits in kraft recovery boilers' -- subject(s): Fume control, Sintering, Sulphate pulping process, Paper industry
Describe what effects sintering press force will have on two specific ceramic materials?
the sintering press force on porcelein allows a ceramic such as porcelein to be moulded into the right shape p.s. Donald is great and shuold rule the world
What is sinter?
Sintering is a process used when manufacturing ceramic or steel objects. The method of sintering is when objects are made from small particles being heated in a furnace below their solid state, which cause the particles to weld to each other.
