A. new thermal filler
(1) Superfine miniaturization of heat-conducting filler (2) Fabrication of high-orientation packing (3) Preparation of three-dimensional carbon fiber
B. Modification of filled particles
The thermal conductivity of the system depends not only on the thermal conductivity of the filler itself, but also on the extent to which the surface of the particle is easily wettable. This is because the filler indicates that the degree of wetting affects the degree of bonding between the filler and the substrate, the thermal barrier at the interface between the substrate and the filler, the uniform dispersion of the filler, the amount of filler added, and so on. So it is important to modify the filled particles.
C. Selection of process conditions
After determining the thermal filler, another major factor in determining the thermal conductivity of the system is the processing of composite materials. Such as the combination of particles and matrix, the thermal conductivity of the thermal conductive rubber prepared by the solution mixture is obviously better than that of the direct thermal reaction. The temperature, pressure, packing and the order of feeding of the various additives Will also affect the thermal conductivity of the system to a large extent, such as thermal silicone rubber, high thermal conductivity of the majority of high temperature vulcanized silicone rubber, and room temperature vulcanized silicone rubber thermal conductivity are low, this is due to the requirements of room temperature Vulcanized silicone rubber has a good process performance, the viscosity of the compound can not be too large, so can not add too much thermal filler; the other hand, because the room temperature vulcanized silicone rubber density is relatively high temperature vulcanized silicone rubber, also affected Its thermal conductivity.
- Piezoelectric ceramics: the so-called piezoelectric effect is that some of the media under the action of force, resulting in deformation, causing the media surface charge, which is positive piezoelectric effect.
- Superconducting ceramics: 1987 American scientists found that yttrium barium copper ceramic at 98K with superconducting properties for the practical application of superconducting materials opened the way to become an important milestone in the study of human superconductivity.
- Capacitor ceramic: Capacitor ceramic can store a lot of power, the current annual production of ceramic capacitors in the world billions of computers in the computer to complete the memory function.
- Thermo-sensitive ceramics: can be sensitive to small changes in humidity, temperature, temperature control.
- Gas-sensitive ceramics: gas-sensing elements can be flammable, explosive, toxic, harmful gas monitoring, control, alarm and air conditioning.
- photosensitive ceramics: made of resistors can be used for photoelectric control, automatic feeding, automatic exposure, and automatic counting.
- Magnetic ceramics: is part of the important information recording materials, but also made of permanent magnet for wind power and other fields.
- In addition there are a lot of other uses of ceramics such as semiconductor ceramics, insulating ceramics, dielectric ceramics, luminous ceramics, photosensitive ceramics, absorbing ceramics, laser ceramics, energy storage ceramics and so on.
- Decorative jewelry: mobile phone shell, case and so on
- Hard coating: cutting tools, mold and so on.
- Protective coating: aircraft engine blades, automotive steel and so on.
- Optical film field: anti-reflective film, high anti-film.
- Architectural glass: sun control film, low radiation glass.
- Solar energy field: solar cells and so on.
- Integrated circuit manufacturing: thin film resistors, film capacitors and so on.
- Information display areas: LCD screen and so on.
- Information storage areas: magnetic information storage.
10. Microelectronics: a variety of microprocessors
From 2004, polystyrene was successfully stripped [1] to 2010 won the Nobel Prize, what is the magic of this seemingly “ordinary” carbon material in a short period of 6 years to create a legendary myth? And look back to see the same family of brothers carbon nanotubes, since 1991 was found nearly 20 years, after the wind and rain, after several ups and downs, but “for others to do wedding dress.”
Graphene is a “monolithic graphite sheet”, which is the basic structural unit of graphite; and carbon nanotubes are cylinders made of crushed graphene (Fig. 1). As a representative of one-dimensional (1D) and two-dimensional (2D) nanomaterials, both are complementary in structure and performance. From the structural point of view, carbon nanotubes are carbon one-dimensional crystal structure; and graphene only by the single-carbon atomic layer, is the true sense of the two-dimensional crystal structure. In terms of performance, graphene has properties comparable to or better than carbon nanotubes, such as high conductivity and thermal conductivity, high carrier mobility, free electron mobility space, high strength and stiffness. At present, the research on carbon nanotubes has reached a certain depth and breadth in terms of preparation technology, performance characterization and application exploration. Composition and structure of the close contact, so that the two methods in the research methods have many similarities. In fact, many of the research on graphene was initially inspired by the research of carbon nanotubes.
Crystals play an important role in modern technology because of its unique nature and structure.
From the internal structure point of view, the crystal has a long-range order grid structure, the formation of the crystal material symmetry and anisotropy and so on. As a result, there is a series of amorphous materials can not have the electrical, optical, mechanical, magnetic and thermal properties, resulting in a reflection of the physical properties of these physical effects, that is, interactive effects. It is these magical interaction that transforms the different manifestations of the energy, light, heat, electricity, and magnetic energy in the crystal, so that the crystal material becomes an indispensable key material for modern technology and its industry.
Crystals have many unique properties, with respect to these properties there are a series of special functional crystal materials, and thus can be prepared into a variety of devices and widely used. It is precisely because of the various properties of the crystals that bring crystals to the rich application.
We can from the life, found a variety of crystal applications, from navigation to space, from microelectronics to optoelectronics, from automatic control to intelligent technology, from computer to communication, from life sciences to medical technology, from civil technology to national defense science and technology, No one high-tech can leave the crystal material. Different crystals have different skills, a variety of artificial crystals in the modern science and technology in the leading position.
