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Thermal Conductive Filler Alumina Powder

Commonly used thermal conductive materials are:  auminum oxide nanopowder, zinc oxide nanopowder, magnesium oxide nanopowder, aluminum nitride, boron nitride, silicon carbide and so on.

Alumina Al2O3 has the advantages of thermal conductivity and insulation, and can be used as a thermally conductive filler to prepare thermally conductive insulating glue, potting glue and other polymer materials. Compared with other fillers, although the thermal conductivity of alumina is not the best, it can basically meet the basic thermal conductivity requirements. In addition, the price of alumina is relatively low, and the source is relatively wide. It is an economical and suitable filler for high thermal conductivity insulating polymers.

Hongwu Nano can produce white alumina micron powder in batches, with narrow particle size distribution, stable process and high thermal conductivity. According to customer feedback, the thermal conductivity can reach between 3-10W/(m*K) according to different filling amounts.

The particle size of alumina powder used for thermally conductive fillers is 1um, 500nm, 300nm, 200nm. The bulk price is more cost-effective.

Thermally conductive alumina can be widely used in different materials such as silica gel, potting glue, epoxy resin, plastic, rubber thermal conductivity, thermal conductive plastic, silicone grease, heat dissipation ceramics, etc. In practical applications, Al2O3 powder filler can be used alone or mixed with other fillers such as AIN and BN.

In order to improve the dispersibility of the alumina powder, the surface of the alumina can be modified with a silane coupling agent or hexadecyltrimethoxysilane.

If you want to know more about the thermal conductivity of alumina, please feel free to consult online at any time!

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Nano Silver Ion Antibacterial Liquid（colloidal silver）Used For Continuous Sterilization Of Mobile Phone Antibacterial Protective Film

According to a notice issued by the Ministry of Industry and Information Technology of China at the end of July 2017, as of the end of the second quarter, China’s mobile phone users reached 1.365 billion, of which 4G users reached 888 million, accounting for 65.1%. With the widespread use of smart phones, mobile phones have become the most inseparable necessities for most people every day. Communication via WeChat via telephone, convenient online shopping, universal use of mobile payment, mass video entertainment teaching… all kinds of necessary use occasions, new mobile phone models are constantly being produced, making mobile phones a “beloved thing” for many people.

 

However, with the gradual lengthening of the “honeymoon period” between people and mobile phones, health problems caused by mobile phones have also begun to become people’s hidden worries. The convenience, anytime and frequent use of mobile phones has made it a “hotbed” of bacteria and viruses in the public and personal hygiene fields. Various harmful bacteria and even viruses lurking on the sliding or reading screen make this square thing. It has become a hygienic corner that is difficult for even a clean addict to clean up.

 

Let the screen protector, a common accessory for mobile phones, protect the phone while reducing the potential hazards of a variety of bacteria and viruses, and become people’s personal health guard! This magical idea was realized by Fujifilm. In 2015, Fujifilm developed a Hydro Ag+ silver ion mobile phone antibacterial protective film. This product combines Fujifilm’s 80 years of research results on “silver halide” and “precision coating” technology in the film field, which can quickly and long-term kill It kills bacteria and viruses, and the antibacterial effect reaches “medical grade”. The antibacterial time lasts for 18-24 months. It is a cross-age antibacterial product that surpasses traditional technology. It carefully protects the health of all kinds of LCD touch screen device users, and can also satisfy Needed by those who have higher requirements for environmental hygiene.

 

Powerful bactericidal nano silver ion solution—colloidal silver

 

Silver ion, chemical symbol Ag+, is an inorganic antibacterial substance, which is firmly adsorbed on the cell membrane by Coulomb’s gravitation and penetrates the cell wall into the cell to solidify the cell protein, and the cell will die due to the loss of the ability to divide and proliferate. In addition, silver ion Ag+ can also destroy the microbial electronic transmission system, respiratory system, and material transmission system. When the bacteria lose their activity, the silver ion Ag+ is freed from the bacteria and repeated sterilization, so its antibacterial effect is long-lasting. Silver ions have a strong bactericidal ability. As long as each liter of water contains two billionths of a milligram of silver ions, most of the bacteria in the water can be killed. In particular, hexagonal nano silver particles have stronger antibacterial properties than spherical and triangular nano silver particles. In addition, silver ion inorganic antibacterial substances, compared with more organic compound antibacterial substances on the market, have obvious advantages in combating multi-drug resistant bacteria.

 

Fujifilm applied the precision coating technology cultivated in the film to the research and development of the Hydro Ag+ antibacterial film, and developed an unprecedented super-hydrophilic coating structure. The ordinary silver-based antibacterial film can only release silver ions from the antibacterial agent on the surface of the coating film, so the antibacterial performance is low and the duration is short; while the Fuji silver ion Hydro Ag+ antibacterial film uses precision coating technology to make the silver antibacterial The agent realizes a three-dimensional structure in the coating film, and the hydrophilic polymer and hydrophilic group are uniformly erected from the inside to the surface, which can not only absorb moisture in the air, promote the release of silver ions from the silver antibacterial agent, but also allow The silver-based antibacterial agent dispersed in the coating film continuously releases silver ions from the inside to the surface, making the antibacterial and antiviral effects last for 18-24 months, achieving unprecedented high antibacterial performance and high sustained effects.

 

Fuji Hydro Ag+ silver ion antibacterial protective film can not only be applied to mobile phones, but also further developed into a screen protective film for commonly used electronic devices such as tablets and laptops to inhibit the spread of various bacteria and viruses. Do not let mobile phones and other electronic devices Becoming an important part of the spread of germs has great practical significance.

 

Currently abroad, Fujifilm’s Hydro Ag+ silver ion antibacterial protective film is also used in hospitals, medical equipment display screens and other places and facilities that have high requirements for sanitary conditions.

 

In a hospital environment where harmful bacteria and even super bacteria are concentrated, it is not enough to ensure that the screens of imaging equipment frequently operated by medical staff are kept hygienic. Regular cleaning alone is not enough. The screen protection film, which can be antibacterial and antiviral by itself, is not easy to be contaminated with various pollutants, can greatly reduce the daily cleaning and disinfection burden of medical workers. It is conceivable that in the areas covered by Fuji Hydro Ag+ silver ion antibacterial protective film, “health and peace of mind” can be more realized. At home, mothers can safely allow their children to operate mobile phones, ipads, and Kindles for interactive learning; in laboratories, food stores and other places, researcher operators can reduce the degree of worry about the uncleanness of the operating screen; in ATMs, self-service ticketing systems , Self-service registration machines and other public facilities, the public’s health is also an escort.

 

Continuously create exciting and revolutionary technologies, products and services, and become a force to increase the infinite possibilities of future business and life. Fujifilm has been practicing.

 

Hongwu Nano is mainly engaged in the R&D, production, sales and after-sales of micro-nano silver products. The series of products include: antibacterial colloidal silver，nano-silver antibacterial dispersion, nano-silver particle antibacterial solution, nano-silver powder, ultra-fine silver powder, flake silver powder, conductive silver powder , Bright silver powder, silver-coated copper powder, etc. The company currently has an annual production capacity of 3 tons of nano silver and 5 tons of conductive silver powder. Welcome to contact with us!

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Four common metal conductive powders

Conductive materials can conduct current well because they have a large number of charged particles that can move freely under the action of an electric field, including conductor and superconducting materials.

The following are the four most widely used metal conductive materials.

Pure silver conductive powder (Ag99.99%)

1) Flake:

Common available particle size: <1um, 1-3um, 3-5um, 5-8um, 8-10um, particle size, and apparent density can be customized according to requirements. Flake silver powder with low apparent is available.

Appearance: silver gray with metallic luster

Application: Flake silver powder is a high-performance conductive filler material with good oxidation resistance. Flake Ag particle is the main raw material for making conductive coatings, membrane switches, conductive inks, conductive rubber, conductive plastics, and conductive ceramics.

Flake Ag powder is an ideal raw material for good low-temperature polymer slurry, conductive paint and electromagnetic shielding paint. The coating prepared with flake silver powder has good fluidity, anti-settling and large spray area.

2) Spherical silver conductive powder:

Common particle size: <1um, 1-3um, 3-5um，5-8um，etc

Application: Near-spherical silver powder is mainly used as conductive filler for high-temperature sintered conductive paste.

There is no absolute standard for silver powder as a conductive filler. The choice of silver powder should be based on the corresponding adhesive, the target conductor material, the physical and chemical properties of the film, and the reliability requirements.

 

Silver coated copper conductive powder (common particle size is 1-3um, 3-5um, 5-8um, 10um, Ag content ranges from 3%-35%)

Features:

1) Silver coated copper powder has adjustable superfine particle size.

2) Ag coated Cu powder has several shapes, such as spherical, flake, dendritic, etc.

3) Silver-coated copper powder has excellent conductivity and lower cost, which can replace some applications of pure silver powder.

4) Silver-coated copper powder has good oxidation resistance and dispersion, and can be used in medium and low temperature slurry.

Application range: It can be widely used in conductive adhesives, conductive coatings, polymer pastes, and various industries that require electrical conductivity and static electricity, electromagnetic shielding, and surface metallization of non-conductive materials.

Silver-coated copper powder can be widely used in conductive adhesives, conductive coatings, polymer pastes, and various fields of microelectronics technology that need to conduct electricity and static electricity, and non-conductive materials surface metallization. It is a new type conductive composite powder. Ag-Cu powder is widely used in the fields of electrical conductivity and electromagnetic shielding in various industries such as electronics, electromechanics, communications, printing, aerospace, and military industries, such as computers, mobile phones, integrated circuits, various electrical appliances, electronic medical equipment, electronic instruments, etc., so that products are not interfered by electromagnetic waves, while reducing the harm caused by electromagnetic radiation to the human body, as well as the conductivity of colloids, circuit boards, and other insulators, to make the insulated object have good electrical conductivity.

 

Pure copper powder (Cu 99%+)

Common particle size: <1um, 1-3um, 3-5um, 5-8um, etc.

Features: spherical and flake shape, uniform particle size, good dispersion, high crystallinity

Applications: Manufacture of terminals and internal electrodes of multilayer ceramic capacitors(MLCC), electronic components and electronic pastes, etc.

Pure nickel powder (Ni 99.7%): Common particle size: 1-3um

As a functional conductive filler, nickel powder can be added in coatings, adhesives, inks, plastics, rubbers, and can be made into conductive, electromagnetic shielding, anti-static  products, to be used in electronics, electromechanics, communications, printing, aerospace, weapons and other industrial sectors in the field of electrical conductivity. Such as computers, mobile phones, electronic medical equipment, electronic instruments and meters.

Guangzhou Hongwu Material Technology Co., Ltd. supplies the conductive materials mentioned above, with reliable high and stable quality, reasonable prices and excellent customized service.

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Antibacterial Mechanism and Use of Zinc Oxide Nanoparticles

Nano zinc oxide ZNO is a new type of multifunctional fine inorganic material. Due to the miniaturization of particles, nano zinc oxide powder produces surface effects, small size effects, quantum effects and macro quantum tunneling effects that are not available in bulk materials. It exhibits many special properties, such as non-toxic, non-migrating, fluorescent, piezoelectric, antibacterial and deodorizing, absorbing and scattering ultraviolet rays, etc. Due to the abundant sources of ZnO raw materials and low prices, while zinc is also a mineral element necessary for the human body, nano-ZnO has become one of the hotspots in the research of inorganic antibacterial agents.

Nano-zinc oxide also has many new uses in the field of science and technology, such as manufacturing gas sensors, phosphors, antibacterial materials, ultraviolet shielding materials, varistors, image recording materials, piezoelectric materials, pressure-sensitive materials, varistors, high-efficiency roughness, and magnetism. Materials and plastic films, etc.

There are two antibacterial mechanisms of nano-zinc oxide ZNO:

Photocatalytic antibacterial mechanism. That is, nano-zinc oxide can decompose negatively charged electrons in water and air under the irradiation of sunlight, especially ultraviolet light, while leaving positively charged holes, which can stimulate oxygen change in the air. It is active oxygen, and it oxidizes with a variety of microorganisms, thereby killing the bacteria.

The antibacterial mechanism of metal ion dissolution is that zinc ions will gradually be released. When it comes into contact with the bacteria, it will combine with the active protease in the bacteria to make it inactive, thereby killing the bacteria.

The antibacterial finishing and research on cotton fabrics by nano-zinc oxide and ordinary zinc oxide found that the antibacterial effect of nano-zinc oxide is the result of two antibacterial mechanisms of photocatalysis and metal ion elution. Nano-zinc oxide has antibacterial properties against Staphylococcus aureus Stronger than E. coli, the smaller the size of the nanoparticles, the stronger the photocatalytic effect.

The practical applications of nano-zinc oxide ZNO in antibacterial and anti-ultraviolet functions are summarized as follows:

The field of daily necessities

Applications in apparel, such as sweatshirts, blouses, uniforms, trousers, professional wear, swimwear and children’s wear. It is also used in industry and decoration, such as: advertising cloth, outdoor decoration cloth and so on.

Professional hygiene

For medical use, the antibacterial polyester staple fiber of nano-zinc oxide can be blended with cotton to make hospital bed sheets, surgical gowns, doctor work clothes, patient clothes, etc. For civilian use, it can be used in the food industry and various bedding, furniture cloth, decorative cloth, etc., sterile surgical gowns, sterile masks, sanitary covering materials, etc.

Fields of outdoor work

The anti-ultraviolet properties of nano-zinc oxide make it can be used to produce all kinds of parasols, curtains, transportation tarps and all kinds of tent cloths.

If you need to use nano zinc oxide powder for your application, please contact us.

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Nano cesium tungsten oxide plays an important role in glass heat insulation

The promotion and application of energy-saving technologies have reached a global consensus, and many countries have successively introduced related policies. A large proportion of building energy consumption is lost through glass doors and windows. Similarly, in the hot summer, the sun’s exposure through the car glass is unbearable for drivers and passengers, accelerating the aging of the vehicle interior, and greatly increasing fuel consumption, increasing emissions, and damaging the environment. Therefore, it is necessary to find a glass heat-insulating agent that is both transparent and heat-insulating.

Cesium-doped Tungsten Oxide/Cesium Tungsten Bronze is an inorganic nanomaterial with good near-infrared absorption. It has uniform particles, good dispersibility, environmental friendliness, strong light transmission ability, good near-infrared shielding performance, and high transparency. Stand out from other traditional transparent insulation materials. It is a new type of functional material with strong absorption in the near-infrared region (wavelength 800-1200nm) and high transmittance in the visible light region (wavelength 380-780nm).

 

Chinese name: Cesium Tungsten Oxide/nano Cesium Tungsten Bronze 

English name: Cesium Tungsten Bronze，Cs0.33WO3 nanoparticles

CAS number: 189619-69-0

Molecular formula: Cs0.33WO3

Molecular weight: 276

Appearance: dark blue powder

 

At the same time, as a new type of automotive glass heat insulation agent, nano cesium tungsten oxide has the best near-infrared absorption characteristics. Usually, adding 2 g per square meter of coating can achieve an infrared blocking rate of more than 90% at 950 nm and more than 70% at the same time. The visible light transmittance.

The heat-insulating agent has been widely recognized by many glass manufacturers. This heat-insulating agent is used in the production of coated heat-insulating glass, coated heat-insulating glass, and laminated heat-insulating glass, which can significantly improve the comfort of the human body and save energy. . Nano cesium tungsten oxide can be said to be a kind of transparent heat-insulating nano powder. What you need to know is that cesium tungsten bronze nano powder is not really “transparent”, but a dark blue powder. “Transparency” mainly refers to the heat insulation dispersion, heat insulation film and heat insulation paint prepared from cesium tungsten bronze all exhibiting high transparency. Experts said that among them, the production of thermal insulation coatings needs to use film-forming materials, such as acrylic resin. Acrylic resin has excellent color and luster, good light and weather resistance, resistance to ultraviolet radiation without decomposition or yellowing, gloss and color retention, and can maintain the original color for a long time. Acrylic resin is often used in combination with other resins as a film-forming substance for transparent thermal insulation coatings. Some experts use polyurethane acrylate water-based resin as the film-forming material and nano-cesium tungsten bronze as heat-insulating particles to prepare transparent heat-insulating coatings, and apply them to architectural glass. Studies have shown that the coating has a transmittance of about 75% in the visible light region.

Hongwu Nano Company is now supplying nano-tungsten oxide in batches, including yellow tungsten, blue tungsten, purple tungsten, and nano-cesium tungsten oxide. The quality is reliable and you can directly seek quotations online. Welcome to cooperate.

 

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Colloidal gold used in immunolabeling technology

Colloidal gold is a kind of nanomaterial widely used in immunolabeling technology. Colloidal gold technology is a commonly used labeling technology, which is a new type of immune labeling technology that uses colloidal gold as a tracer marker for antigens and antibodies, and has its unique advantages. In recent years, it has been widely used in various biological research. Almost all the immunoblotting techniques used in the clinic use its markers. At the same time, it can be used in flow, electron microscopy, immunology, molecular biology and even biochip.

Nano colloidal gold is negatively charged in a weak alkali environment, and can form a firm bond with the positively charged groups of protein molecules. Because this bond is electrostatic bond, it does not affect the biological properties of protein.

In essence, the labeling of colloidal gold is the encapsulation process in which proteins and other macromolecules are adsorbed to the surface of colloidal gold particles. This spherical particle has a strong ability to adsorb proteins and can bind non-covalently to staphylococcal A protein, immunoglobulin, toxin, glycoprotein, enzyme, antibiotic, hormone, and bovine serum albumin polypeptide conjugates.

In addition to protein binding, colloidal gold can also bind to many other biological macromolecules, such as SPA, PHA, ConA, etc. According to some physical properties of colloidal gold, such as high electron density, particle size, shape and color reaction, coupled with the immune and biological properties of the binder, colloidal gold is widely used in immunology, histology, pathology and cell biology and other fields.

Hongwu nanomaterial is supplying various ppm of colloid gold,Nano gold powder , such as 10000ppm, 5000ppm, 2000ppm, 1000ppm.ruby red liquid,competitive price,worldwide shipping, feel free to contact us at hwnano@xuzhounano.com.

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Three commonly used nano-materials used in transparent thermal insulation coatings

Nano thermal insulation coatings can be used to absorb ultraviolet rays from the sun, and are often used in current decoration buildings. Water-based nano transparent thermal insulation coating not only has the effect of high efficiency and energy saving, but also has the comprehensive advantages of green environmental protection, health and safety. As an alternative to solvent-based glass nano transparent thermal insulation coating, its market prospect is broad, and it has profound practical significance and positive social significanceis  for energy conservation, emission reduction and environmental protection advocated by the country.

Thermal insulation mechanism of nano transparent thermal insulation coating:The energy of solar radiation is mainly concentrated in the wavelength range of 0.2～2.5μm, and the specific energy distribution is as follows: the ultraviolet region is 0.2～0.4μm accounting for 5% of the total energy; the visible light region is 0.4～0.72μm, accounting for 45% of the total energy ; The near-infrared region is 0.72 ~ 2.5μm, accounting for 50% of the total energy. It can be seen that most of the energy in the solar spectrum is distributed in the visible and near-infrared regions, and the near-infrared region accounts for half of the energy. Infrared light does not contribute to the visual effect. If this part of the energy is effectively blocked, it can have a good heat insulation effect without affecting the transparency of the glass. Therefore, it is necessary to prepare a substance that can effectively shield infrared light and transmit visible light.

Three commonly used nanomaterials used in transparent thermal insulation coatings:

1. Nano ITO

Nano ITO (In2O3-SnO2) has excellent visible light transmittance and infrared blocking characteristics, and is an ideal transparent thermal insulation material. Since indium metal is a scarce metal, it is a strategic resource, and indium raw materials are expensive. Therefore, in the development of transparent heat-insulating ITO Indium Tin Oxide Nanopowder coating materials, it is necessary to strengthen process research to reduce the amount of indium used on the premise of ensuring the transparent heat-insulating effect, thereby reducing production costs.

2. Nano CS0.33WO3

Cesium tungsten bronze transparent nano thermal insulation coatings stand out from many transparent thermal insulation coatings due to its environmental friendliness and high thermal insulation characteristics, and currently have the best thermal insulation performance.

3. Nano ATO

Nano ATO antimony-doped tin oxide coating is a transparent heat-insulating coating material with good light transmission and heat insulation performance. Nano antimony tin oxide (ATO) has good visible light transmittance and infrared barrier properties, and is an ideal thermal insulation material. The method of adding nano tin oxide antimony to the coating to make a transparent thermal insulation coating can effectively solve the thermal insulation problem of glass. Compared with similar products, it has the advantages of simple process and low cost, and has extremely high application value, broad application and high market expectation.

Features of nano thermal insulation coatings:

1. Insulation

Nano thermal insulation coatings can effectively block infrared and ultraviolet rays in sunlight. When sunlight penetrates the glass and enters the room, it can block more than 99% of ultraviolet rays and block more than 80% of infrared rays. Moreover, its heat insulation effect is very good, can make a difference of 3-6˚C for the indoor temperature, can keep the indoor air cool.

2. Transparent

The surface of the glass coating film is very transparent. It forms a film layer of about 7-9μm on the surface of the glass. The lighting effect is very good and will not affect the visual effect. Especially suitable for hotels, office buildings, residences, etc, which require high lighting requirements.

3. Keep warm

Another feature of this material is its good insulation effect, because the micro-film layer on the surface of the glass coating blocks indoor heat, maintains the heat and temperature in the room, and makes the room reach a state of insulation.

4. Energy saving

It is precisely because the nano thermal insulation coating has the effect of heat insulation and heat preservation, it makes the indoor temperature and the outdoor temperature rise and fall in a balanced manner, so it can reduce the number of switches on and off of air conditioning or heating, saving a lot of expenses for the family.

5. Environmental protection

Nano thermal insulation coating is also a very environmentally friendly material, mainly because the coating film does not contain benzene, ketones and other ingredients, nor other harmful substances, so it is truly green and environmentally friendly and meets international environmental quality standards.

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The Global Market’s Demand for Nano Silver is Growing Rapidly

At present, nanotechnology is considered to be the most revolutionary technology, which has had a significant impact on social livelihoods through its multidisciplinary applications. Silver nanoparticles (AgNPs) is a metal nanoparticle material that has been widely researched and applied. At present, the global market’s demand and enthusiasm for silver nanoparticles (AgNPs) continues to increase.

Chinese scholars have discovered a new strategy of highly effective antibacterial nano-silver, sterilization does not produce drug resistance.

Professor He from the School of Chemistry and Chemical Engineering of Hefei University of Technology and Professor Cha from the School of Food and Bioengineering have successfully developed a nano-silver aqueous dispersion with weak acid response recombination function, which can be sprayed on the wound to achieve an efficient target for drug-resistant bacterial infections For treatment, it eliminates bacteria while not producing resistant bacteria, and thus proposes a new high-efficiency antibacterial strategy. Relevant results were published online in the “Advanced Functional Materials” magazine a few days ago.

Scientists hope that a material that they claim can kill bacteria and viruses can be used in masks to help deal with the new coronavirus pneumonia epidemic.

The main component of this material is nano-silver with antibacterial properties, which is prepared by using a melt-blown process. Alexander Zanovich Medvedev, who worked on the project, explained that this made polypropylene fibers with a diameter of 1 micron. Medvedev is currently in charge of the work of a laboratory of the Siberian branch of the Russian Academy of Sciences. It is not clear whether this research has been published in a peer-reviewed journal.

Medvedev said in a statement that he and his colleagues put the finished material on the inner layer of a conventional three-layer medical mask. The chief researcher of the Institute of Chemistry and Technology Nikolai Zakharovich Liakhov said that the researchers tested the performance of the mask against influenza A virus, staphylococcus and E. coli.

When the research team compared this new material with the material of ordinary masks, it was found that the number of viruses passing through the latter was 10,000 times higher.

Nano-silver medical masks, using new nano silver antibacterial patented technology, developed and created the first reusable nano-silver non-woven medical masks in Guangdong Province. Based on the calculation of continuous wearing for 8 hours a day, the life cycle of a nano-silver non-woven mask can reach 7 days.

In addition to the conventional single-layer spunbonded non-woven fabric on both sides of the inside and outside, and the middle melt-blown non-woven fabric, the mask also contains a layer of nano-silver non-woven fabric, which has strong water absorption, releases high-activity silver ions, and kills bacteria and viruses. When breathing moist gas, it will release silver ions for a long time to kill bacteria.

The test results of the Hong Kong Polytechnic University wearing experiment show that after 8 hours of wearing, the total number of bacteria on the surface of this type of mask is still far below the range allowed by the national standard, and it can be used repeatedly; the test report of the NELSON laboratory approved by the US FDA shows that the The bacterial filtration rate of the type mask is over 99.7%. After 18-24 hours of continuous use, its bacterial content still does not exceed the range allowed by the national standard, and it can be used repeatedly for a long time.

The research team of Shanghai University has developed 6Cr16MoMA ultra-high hardness stainless steel containing nano-antibacterial silver, which has high strength plastic toughness and sterilization function. The core technology has been authorized by the national invention patent.

In 2017, the Antibacterial Material Testing Center of the Institute of Physics and Chemistry of the Chinese Academy of Sciences tested the antibacterial properties of the material and found that the antibacterial rates for E. coli and Staphylococcus aureus were both ≥99%. In 2019, after further testing by Shanghai Ingeer Testing Technology Service Company, the material has an antibacterial rate of 99.61% against Candida albicans and an antibacterial rate of Pseudomonas aeruginosa ≥99.99%. This stainless steel material not only has a high antibacterial rate, but also has excellent mechanical properties. It is used in the production of household kitchen knives. Its cutting performance is equivalent to that of high-end imported kitchen knives. It is much better than similar domestic products and is at the leading domestic level. Get latest nano silver price from https://www.hwnanomaterial.com.

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Knowledge about flake silver powder and grinding aids

The properties of flake silver powder are stable, and the particles are in surface or line contact, so the resistance is relatively low and the conductivity is good. Flake silver powder is one of the important materials for electronic components, and is widely used in electronic components such as membrane switches, filters, carbon film potentiometers, silver nanoparticles tantalum capacitors, and semiconductor chip bonding.

 

The key process for preparing flake silver powder is ball milling. The process of ball milling is more complicated. The quality of flake silver powder’s micro morphology, diameter-to-thickness ratio, and surface condition all depend on the ball milling process. The main influencing factors of ball milling include ball gradation, ball mill speed, ball-to-material ratio, ball milling time, type and amount of grinding aids, ball milling atmosphere, ball milling temperature and so on.

 

Different ball milling aids have different effects on the performance of the powder. If only absolute ethanol is used as the wet milling medium, the prepared silver powder particles are coarser and the silver flakes are larger, but they are very bright. Using oleic acid as the ball milling medium, the prepared powder is better in flakes and the color is silver gray. Using stearic acid as the ball milling medium, the prepared silver powder has a flake size and the color is silver gray. The color of the silver powder prepared by the compound auxiliary agent is bright gray.

 

The so-called grinding aids are chemical substances that can significantly improve the efficiency of crushing operations and reduce the energy consumption per unit of product. It includes organic and inorganic matters. The main purpose of adding a grinding aid is to improve the grindability of the material, reduce the interaction between particles and the adhesion of fine particles on the grinding medium, and provide the fluidity of the material in the mill, thereby improving the fineness and quality of the product.

 

There are mainly two views on the mechanism of action of grinding aids. One is the theory of “adsorption reduces hardness”, which believes that the adsorption of grinding aid molecules on particles reduces the surface energy of the particles or causes dislocations in the crystal lattice near the surface layer, thereby reducing the strength and hardness of the particles. The second is the theory of “pulp rheology adjustment”, which believes that the grinding aid reduces the viscosity of the pulp and promotes the dispersion of the particles by adjusting the rheological properties of the pulp and the surface electrical properties of the mineral particles. Both theories explain the mechanism of the grinding aid from a certain aspect, but the grinding aid acts on the powder in a highly complex ball milling environment, so it should be considered comprehensively.

 

According to experiments, the amount of ball milling aids added has a great relationship with the bulk density. With the increase in the amount of ball milling aids, the bulk density of the powder continues to decrease. When the amount of ball milling aids is over 1.5%, the bulk density of the powder gradually increases, so the amount of ball milling aids can be considered to be controlled around 1.5%.

 

Hongwu Nano produces flake silver powder with low bulk density and normal bulk density. In addition, customers for different applications have different requirements for whether to wash off the grinding aids, and we can deal with them accordingly. Get nano silver price from us quickly!

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Nano materials in concrete

Application of nanotechnology in concrete

Concrete is the basic building material and widely used in a variety of buildings and structures. Since the 21st century, concrete engineering is upsizing, the engineering environment becomes complicated, and the ever-expanding application fields, people have put forward higher requirements for concrete materials. Nanotechnology can improve the performance of concrete and greatly expand the application.

Nanomaterials can effectively improve the performance of concrete

1. Nano silica/SiO2
Nano SiO2 powder is a superfine powder with silicon or silicone chloride hydrolyzed to form hydroxyl groups on the surface. In the field of cement concrete, nano silica can increase the strength and durability of concrete due to its strong pozzolanic activity, micro-aggregate filling effect and nucleation.

2. Carbon nanotubes
The carbon nanotubes are tubular, light in weight, and the hexagonal structure is perfectly connected, which is a good high-strength fiber material. The proper amount of carbon nanotube powder into the cement can effectively improve the pore structure and microcracks of the material, and play a bridging role, thereby improving the mechanical properties of the cement substrate. get details about carbon nanotubes price from https://www.hwnanomaterial.com/.

3. Nano calcium carbonate
Nano CaCO3 is a low-activity mineral micropowder material with a cost of about one-tenth that of nano-SiO2. After being doped with nano calcium carbonate powder, under the combined action of micro-aggregate effect and crystal nucleus effect, the bulk density is increased, which helps to improve the flexural and compressive strength. The nucleation of nano-calcium carbonate can refine the crystal form, improve the interface structure and improve the durability of concrete.

4. Nano carbon fiber
Nano-carbon fiber is a novel nano-carbon material which is formed by the rolling of a layered graphite sheet. Compared with carbon nanotubes, it has a relatively low cost and has a great advantage in production. Study found that the addition of nano-carbon fiber not only makes the concrete have excellent pressure-sensitive properties, but also improves its mechanical properties.

Nanotechnology expands the application of concrete
1. Concrete that absorbs electromagnetic waves
2. Purifying air concrete
3. Antibacterial concrete
4. Automatic humidity control concrete
5. Ecological concrete
6. Smart concrete

High-performance, high-functionalized concrete as a high-tech in the field of building materials provides a new opportunity for the development of traditional building materials. The development of traditional concrete materials is entering the track of technological innovation. Among them, nanomaterials and nanotechnology will play an increasingly important role in improving the durability and functionality of concrete.