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Silicon carbide whiskers can significantly improve the service life of resin diamond grinding wheels

The diamond grinding wheel uses diamond abrasive as raw material, and uses metal powder, resin powder, ceramics and electroplated metal as binders respectively. The circular bonded abrasive tool with a through hole in the center is called diamond grinding wheel (alloy grinding wheel).

The resin-bonded diamond grinding wheel generally has a low life and cannot meet the requirements of advanced numerical control machine tools. The short life is mainly due to the poor wear resistance of the resin bond itself or the low holding force on the diamond, which causes the diamond abrasive particles to fall off prematurely during the grinding process. Therefore, how to improve the wear resistance of the resin bond and improve the holding force of the resin on the diamond has become the key to improving the service life of the resin bond diamond grinding wheel.

The addition of silicon carbide whiskers can greatly improve the strength, hardness, heat resistance, polishing, etc. of the bond and the grinding wheel. Silicon carbide whiskers have unique mechanical and physicochemical properties such as high hardness, high strength (toughness), and excellent wear resistance, so they are widely used in metals, ceramics, plastics, etc.

Strengthening and toughening of materials and composite materials to improve the strength of composite materials and prevent shrinkage and deformation. The shape of silicon carbide whiskers is like needles, especially its Webster hardness is close to diamond and has good toughness and wear resistance, and compared with abrasive grains, even if the diameter is the same as the grain size of abrasive grains, there are whiskers of a certain length that are combined with The agent has a relatively large bonding area and bonding strength, which greatly improves the service life of the grinding wheel.

The β-type micron-sized silicon carbide whiskers produced by Hongwu Nano have the characteristics of high purity and good morphology, and are the preferred materials for strengthening and toughening of various metal-based, ceramic-based and resin-based composite materials. Its strengthening and toughening effect and scope of application are unmatched by other materials.

Beta silicon carbide whiskers are needle-like single crystals. As an atomic crystal, it has low density, high melting point, high strength, high modulus, low thermal expansion rate, and excellent characteristics such as wear resistance, corrosion resistance, high temperature resistance, oxidation resistance, etc. It is mainly used for metal base, ceramic base , Reinforcement and toughening of resin-based composite materials, significantly improve the properties of composite materials.

Its main physical performance indicators are as follows:
Whisker diameter Diameter: 0.1-2.5um
Whisker Length: 10-50um
Density: 3.2g/cm2
Hardness: 9.5 Mobs
Modulus Modulus: 480GPa
Tensile Strength Strength of extension: 20.8Gpa
Tolerable temperature: 2960℃

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Low Cost Synthesis of Silicon Carbide Nanopowders

Among modern ceramic materials, silicon carbide (SiC) and silicon nitride (Si3N4) has been successfully used in a variety of high-tech applications. SiC provides the effective combination of mechanical properties. It is widely used as an abrasive material and structure. It has high hardness, chemical inertness, than the melting temperature of the steel wear and oxidation of it for serious conditions such as high temperature sealing valve, rocket nozzle and wire drawing die and extrusion die for bearing applications because of its good wear resistance and corrosion resistance. In the tube by SiC to find its thermal properties and creep resistance of high temperature and hot electron exchange. The heating element from SiC. They can produce a high temperature of 1650 DEG C and medium in the air or inert considerable life. However, with any contact with water or hydrocarbon gas, can influence their age.

Silicon nitride has comparatively lower oxidation resistance and higher thermal conductivity than SiC. Major applications of silicon nitride are as automotive and gas turbine engine parts. It has high strength, fracture toughness and refractoriness which are required properties for ball bearings, anti-friction rollers. It performs remarkably when exposed to molten metal and/or slag.

A combined form of silicon carbide and nitride has been developed as silicon carbide grains bonded in silicon nitride matrix. This Si3N4-bonded silicon carbide is used for some critical applications where very high thermal shock resistance is required. For instance, in particular case of flame-out engine start-up, temperature reaches from ambient to 1600 °C in few seconds followed by an abrupt decrement to 900 °C in less than one second. Si3N4-bonded silicon carbide exclusively endures these conditions.

Traditional methods to produce these ceramic materials are energy intensive and hence expensive. For example, the Acheson process, which is the most widely adapted method to produce commercial-grade SiC, essentially takes 6 – 12 kWh to yield one kg of SiC. An inexpensive method, that uses low cost agro-industrial byproduct, is the pyrolysis of rice husks, first carried out by Lee and Cutler in 1975. Since then many researchers have discussed and used various process routes and modifications to obtain Silicon Carbide Nanopowders and/or silicon nitride, either in particulate or in whisker form, from rice husks.

Morphological studies on RH reveal that micron size silica particles are distributed in cellulosic part of RH. When these silica particles are made to react with carbon in biomass part of RH under specific experimental conditions, silicon carbide can result. Moreover, besides silicon carbide, modifications in process mechanism lead to formation of some other industrially useful products, viz. silicon nitride, silicon oxynitride (Si2N2O), ultra-fine silica, and solar-cell grade silicon.

Related reading: nano particles nano oxides

 

 

 

 

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Nano Element Particles For Cosmetics

Most of the company’s cosmetics are manufacturing nanotechnology products. They are usually used in the brand-name products such as sunscreen and anti aging products. But what is nanotechnology? In fact, this is a scientific field, control aims to molecular and atomic level of substance. It can make the product more clean, more powerful, more light, the most important thing is cheap. It also can make compound is too small, so it provides a faster and more effective results. However, you should understand that this technology has not been thoroughly tested, which means that it is uncertain whether really safe, especially if you put it in your body as you face the most vulnerable part of.

The FDA has not yet made a lot of research about this. It seems that there have been no reported cases of adverse effects yet. However, there are some experts which are wondering about the safety of these products since when particles will become smaller, new chemical properties will emerge. Since these nanoparticles are very small then they can quickly slip through your skin layers. This means that it will have an interaction with your bloodstream and immune system. The result can be toxic and it can possible damage your tissues. All major cosmetics companies which are producing nano products are always testing their products and they make sure that they are following all laws in order to insure the safeness of their products. However, the FDA will only investigate the safeness of a particular product once it is already in the market. The testing for cosmetics which are using nanoparticles still continues.

Of most concern to a consumer’s problem is that it is toxic. Cosmetics manufacturers of nanotechnology products, because they are cheaper, at the same time provide faster results and many benefits. Cosmetics company selling these skin care products, because they claim they can provide more effective results. Most people choose a skin care products, free of parabens as natural or organic products. Choose cosmetics you should know that these products contain some chemicals can enter the bloodstream, may harm your body and when. In the purchase of a product is best to consult your doctor working in the Department of dermatology. Look before you leap, avoid everything that is said by the sales staff. Perhaps these benefits may be short-lived. The best thing about nano products is that it can provide fast results. But in the application to your face, you have to read the label carefully. Know all the ingredients, and each ingredient to understand everything.

The idea behind this new technology is that if the particle is too small then it can provide better results , about nanotechnology is it can reduce the ingredients of the cosmetics into a nano size form. It is usually too tiny which can be 1/1000 of a human hair. These Nano Element Particles will be absorbed by the skin and it will directly go to the lower levels of your skin where it can provide the needed benefits.

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How To Wax Your Car By Nano Diamond Powder

Nano diamond powder is an amazing new product, provide your car with super hydrophobic non wax seal, is guaranteed for one year. Everyone can superhard nano particles contain, will be key will make your car on the surface of billions of.

Learning how to correct the wax the car is every owner should have the skills. This ability is valuable, it goes beyond the work, the results come back to have a look to complete a simple enjoyment. Of course, this kind of feeling is very good, but especially in the long-term value of the job really, you often do.

An effective wax job appropriately applied, safeguards any car from certain minor scratches and hides others, as well as aids in preventing rust especially during the cold months

Showroom Finish For Your Car

That completely new showroom finish is one thing that we all would like to accomplish with our cars. The day you bring an automobile home from the car dealership is often the first and last day it ever appears like that. But this doesn’t need to be. Take time to really learn to wax your vehicle the proper way and you will ensure that it stays looking almost showroom new for much longer time. Obviously, one method to accomplish this look would be to pay to have your vehicle detailed, but where’s the enjoyment in doing that? For this reason, Do-it-yourself, cut costs and enjoy the fruits of your labor.

Researching Car Wax Brands

You will find a variety of brands and designs of automotive wax items available on the market. Take some time to check out the items which are available and find out which of those you believe you may like the best. Often times, consumer rankings value the few less costly brands the most. So, investing in more expensive car waxes, will not necessarily accomplish anything.

Regardless, make certain you stay with a non-abrasive wax to provide the best results.

Preparing Cars for Waxing

Next, perform a thorough cleaning and washing job on the vehicle. Clean it two times if needed to make certain you remove all of the spots you skipped the very first time. Don’t clean it in direct sunlight if it’s hot out, since you really do not want it to dry too quickly. Once it’s clean, you are now prepared to wax. Towel dry any excessive wet areas, especially around the hood.

Waxing a Car Right

Obtain a moisten sponge and squirt a little bit of wax on to the sponge. Give it a try and find out how that amount works best for coverage. Don’t cover much more of a space than you are able to and definitely, don’t too much that it dries before you have completed that area. Make use of a circular motion to rub the wax into the surface of the vehicle. Cover the entire vehicle moving in order surface by surface throughout the entire process so that you won’t miss anything.

Removing the Car Wax

When you return back around to the original surface, the wax you applied is going to be dry. Cloth diapers really are excellent tools for getting rid of excess wax for those who have any available. A terry cloth will even work nicely if it doesn’t have any fresh paint or any other abrasives onto it. Remove the wax using a circular motion in the opposite direction in which you used to apply the wax.

Make certain to remove all the wax by putting sufficient pressure during the wipe off process. Make certain to change towels as frequently as necessary to prevent putting wax back onto the paint surface throughout this activity. This avoids any chance of swirl marks occurring and also any damage to the paint the old wax could cause.

Use clean towel, must pass all the way, to avoid damage and get the best results thoroughly. From the preparatory to the complete cleaning waxing itself and depth, creating the exhibition hall to see you from the start. These represent the boot prompt successful car wax project.

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Synthesis of Metal Alloy Nanoparticles

A simple, convenient, and general method for the synthesis of metal and metal alloy nanoparticles is presented. Irradiation of metal powders in suspension in either aqueous or organic solutions by unfocused 532 nm laser radiation produces nanoparticles with a homogeneous composition proportional to the composition of the starting metal powder mixture. This is demonstrated using UV−vis absorption spectroscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, and modelization. The mechanism of alloy formation is discussed.
This Review is focused on the recent progresses in the synthetic approaches to the precise control of structure, size, shape, composition and multi-functionality of metal and metal alloy nanoparticles. Many of these strategies have been developed based on colloidal methods, and to limited extent, the galvanic and other methods.

Synthesis of Metal Alloy Nanoparticles in Solution by Laser Irradiation of a Metal Powder Suspension. The shape, size and composition often govern the chemical and catalytic properties that are important for electrochemical energy applications. The structure–property relationship and the design in controllable structures and morphologies for specific reactions such as oxygen reduction reaction (ORR) are emphasized.Magnetic nanoparticles have potential applications in high-density memory devices, but their complicated synthesis often requires high temperatures, expensive reagents, and postsynthesis annealing to achieve the desired magnetic properties. Current synthetic methods for magnetic nanoparticles often require post-synthetic modifications, suggesting that the practical application of magnetic nanoparticles will depend on the development of alternative synthetic strategies.
We report a biological template to directly grow magnetic nanoparticles of desired material composition and phase under ambient conditions. A phage display methodology was adapted to identify peptide sequences that both specifically bind to the ferromagnetic L10 phase of FePt and control the crystallization of FePt nanoparticles using a modified arrested precipitation technique.

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Microwave hybrid synthesis of silicon carbide nanopowders

Nanosized silicon carbide powders were synthesised from a mixture of silica gel and carbon through both the conventional and microwave heating methods. Reaction kinetics of SiC formation were found to exhibit notable differences for the samples heated in microwave field and furnace. In the conventional method SiC nanopowders can be synthesised after 105 min heating at 1500 °C in a coke-bed using an electrical tube furnace. Electron microscopy studies of these powders showed the existence of equiaxed SiC nanopowders with an average particle size of 8.2 nm. In the microwave heating process, SiC powders formed after 60 min; the powder consisted of a mixture of SiC nanopowders (with two average particle sizes of 13.6 and 58.2 nm) and particles in the shape of long strands (with an average diameter of 330 nm).
The powders were prepared by a sol-gel process. Dielectric constants (ϵ′) and dielectric loss tangents (tanδ) were measured within the microwave frequency range from 4 to18 GHz. Both ϵ′ and tanδ of pure SiC nanopowder are much higher (ϵ′=40–50, tanδ=0.6–0.7) than for the doped ones over the frequency range. The dielectric parameters decreased with increasing aluminum and nitrogen contents. Infrared (IR) spectra were measured in the range from 500 to 4000 cm−1, showing that the background of pure SiC nanopowder is also much higher than for the doped ones. The possible mechanisms of these promising features of undoped SiC nanopowder are discussed.
By a simple and controlled method, that is, by electroless plating, nickel has been deposited on the surfaces of Silicon Carbide Nanopowders Energy dispersive spectrometry (EDS) spectra show that pre-treatments of the silicon carbide nanoparticles have an important influence on the effect of electroless nickel plating. Transmission electron microscopy images and EDS spectra of silicon carbide nanoparticles before and after electroless nickel plating reveal that nickel has been deposited on the surface of silicon carbide nanoparticles and the deposited nickel and silicon carbide nanoparticles are bound tightly.

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The application of metal nanowires

Metal nanowires can have a variety of forms. Sometimes they appear in the order to non crystal, such as five symmetrical or helix. Electronic in the Pentagon pipe and spiral pipe winding.

This lack of crystal order is because the nanotubes in only one dimension (Zhou Xiang) reflect cyclical, while in other dimensions can have any order to the law of energy. For example, in some cases, nanowires can show five fold symmetry, this symmetry cannot be observed in nature, but can be found in a small amount of atoms contributing to clusters. The five fold symmetry equivalent atoms cluster twenty fold symmetry: Twenty surface body is low energy states of a cluster of atoms, but because the surface of the body twenty can not be repeated indefinitely in all directions and fill the whole space, this order is not observed in the crystal.

In electronic, optoelectronic and nano electronic and mechanical devices, nano wires may play an important role. It also can be used as in the synthesis of additives, quantum devices in the line, field emitters and biological molecular nano sensor.

Metal nanowires can be natural sunlight came together in a very small area in the crystal, light gathering ability is 15 times the average light intensity. Because of the wavelength diameter is smaller than the incident solar light nanowire crystals, can cause the nanowires inside the crystal and the surrounding light intensity of resonance. The study participants, just to get the doctor degree of research on Niels Pohl Peter Klogstrup explained that the photons through resonance emit more concentrated (solar energy conversion is realized in the process of dissemination in the photon), which helps to improve the conversion efficiency of solar energy, so that the solar cell technology nanowires get real ascension based on the.

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Nano silicon semiconductor light-emitting materials research

By changing the quantity of silicon rich, annealing conditions, size and density control oxidation of silicon in silicon Silicon Carbide Nanopowders. Literature that the critical temperature of silicon nanocrystals is 1000oC, and we tested to determine the critical annealing temperature for 900oC nanocrystals. On the right is via the 900oC annealing silicon rich silicon was about high resolution electron microscopy images of 30% silicon rich silicon oxide. Can clear the silicon nanocrystals. On the left corner of the electron diffraction pattern it is.

First observed by Au/ (Ge/SiO2) /p-Si superlattice structure electroluminescence. Right out of high resolution electron microscopy figure four cycle Ge/SiO2 superlattices. The bright line for the SiO2, 2.0nm thickness, Ge thickness of 2.4nm.

The growth of nano SiO2/Si/SiO2 double barrier by magnetron sputtering technique on silicon substrate (NDB) single well potential sandwich structure, the first realization of visible photoluminescence of Au/NDB/p-Si structure. Discovery of electroluminescence peak position, intensity with the nanometer silicon layer thickness (W) changes as synchronous oscillations, as shown on the right. Further tests and analyses show that the oscillation period is equal to the deBroglie wavelength of 1/2 carrier. Lighting model is explained by our group proposed electroluminescence.

For the first time based on SiO2:Si:Er film growth by magnetron sputtering has been achieved on the 1.54 m wavelength as (optical communication window) Er electroluminescence.