Composite effect
The average effect
is the most typical composite effect displayed by the composite material. It may be represented as:
, p is material properties, V is the volume content of the material, the angles C, M, and F represent composite, substrates, and reinforcing body (or functional). Some functional properties of composites, such as conductance, thermal conductivity, density, and elastic modulus, etc. Overall an average effect. For example, if the elastic modulus of the composite is represented by the mixing rate, the composite material of the effect is shown in the
parallel effect, and its components are retained in the composite material. The role, there is no constraint and has no compensation. For the enhancer (such as fiber) and the matrix interface combined with a weak composite, the composite effects shown can be considered as a parallel effect.
Pirate effect constitutes the matrix and enhancer of the composite, supplemented with each other, thereby improving comprehensive performance, showing the phase supplement effect.
When the effector matrix is composite the enhancement, if the group separation properties are constrained, the overall performance is improved, and the phase abutment is displayed after composite.
In the glass fiber reinforced plastic, after the surface of the glass fiber is treated, the composite material consisting with the resin matrix is reinforced by the combination of the interface, so that the tensile strength of the material is caused. Composites composed of unprocessed fibers can be 30-40%, and the wet strength retention rate is also significantly improved. However, this strong interface is simultaneously caused by a decrease in the impact properties of the composite material.
Therefore, in the metal base, the ceramic base enhancement composite is not necessarily the most suitable. The effects of the phase supplement and the imba are often common.
Obviously, the polyhydration effect is desirable, and the imbalance should be avoided as much as possible.
All of this can be achieved by the design of the corresponding composite material.
Carbon fiber cement-based composite pressure sensitivity is affected by many factors, and the pressure sensitive mechanism is very complicated. The carbon fiber cement-based composite interface is a bridge between the carbon fiber and the cement matrix. The interface performance directly affects the comprehensive performance of the composite material, and an important role in the pressure sensitivity of the material. With the funding of the National Natural Science Foundation of China, on the basis of existing research, the interfacial performance of carbon fibers on the surface treatment of carbon fibers on the surface treatment of material pressure sensitivity was studied by the development of carbon fiber cement-based composites. Effects of material pressure sensitivity and mechanism of action. The specific work and research results are as follows: (1) The effects of different carbon fiber surface treatment on the pressure sensitivity of carbon fiber cement - based composites were studied. The non-surface-treated carbon fiber-cement substrate is low, which is easy to delay. Various oxygen-containing polar groups of surface treated fiber surface increase, facilitating the formation of chemical bonds, improving the bond strength and toughness of the interface, thereby improving material pressure sensitive reliability and repetition. [I]
Nonlinear effects include product effects, system effects, induction effects, and resonance effects, which have been recognized and utilized, and provides a lot of freedom for functional composite materials; Some effects have not been fully understood and utilized.
The multiplying effects of the two types of conversion effects are combined together, and multiplied effects can occur.
For example, when a material having an electromagnetic effect is composite with a material having a magneto-optical effect, a composite material having an electro-optical effect will be produced.
Therefore, a functional material x / y and another of the two properties that have two performances can be used to comparatively explicitly represented by the following formula, namely:
, X, Y, and Z represent various physical properties, respectively. The above formula is in line with the product expression, so it is called a multiplied effect.
| A Phase Nature X / Y | B Phase Properties Y / Z | Composite Product Properties (x / y) (Y / Z) = X / Z |
| Visibility Effect Compact effect piezoelectric Effect Magnetostrictive Effect Light Transfer Effect Blinking Effect Hot Deformation Effect | < Td width = "191"> pressure sensitive resistance effect piezoelectric effect pressure luminous effect magnetoresistance effect photoresist radiation induced conductivity Thermistor effect |
The magnetoelectric coupling effect is that electrodization can be generated when the material is in outer magnetic field conditions, or appears under electric field conditions Magnetization phenomenon. Early studies were mainly concentrated on mono-phase compounds having magnetoelectric effects, however the magnetoelectric effects of single-phase materials were small, and generally can be achieved at low temperatures, and thus cannot be applied. Nanzhi Wen, etc. will have piezoelectric electricity The composite material formed by the effect and magnetostrictive two materials is formed with a large magnetoelectric effect. The principle is that the magnetic-force conversion and piezoelectric material generated by the magnetostrictive material is generated by the interface. Stress transfer and coupling effects to achieve new magnetoelectric coupling effects. [II]
Zirconate titanate lead hot release ceramic material can be directly applied to thermoelectric energy conversion and infrared detection, low temperature in ferroelectric FRL) 2 The nonlinear thermal release effect produced during the ferroelectric high temperature (FRH) phase can be 10 times the linear thermal release effect, and the nonlinear effect can greatly improve the thermoelectric conversion efficiency and the detection rate due to different composite. The situation of ion diffusion is different, and the nonlinear thermal release effect also has a respective feature: the material prepared in parallel has a wide phase change temperature range, and there is a nonlinear thermal release effect in this range; The nonlinear thermal release effect of the material prepared in a laminated manner is affected by the alignment order of the chemical component; the heat release output prepared in the mixed manner is relatively equalized, but the temperature width is more narrow. [III]
Induction effects under certain conditions, one component material in the composite can change the structure of another component material by inducing action, thereby changing overall performance or generating a new effect.
This induction behavior has been discovered in many experiments, and it is also found on both sides of the composite interface.
For example, the crystalline fiber reinforcement has a crystalline-oriented alignment of the amorphous matrix induced crystalline or crystalline matrix. In carbon fiber reinforcing nylon or polypropylene, due to the induction of the matrix due to the carbon fiber surface, the crystalline state and the number thereof have changed, such as a lateral pendant, etc., this effect plays a special role in nylon or polypropylene. .
Resonance effects Two adjacent materials can produce mechanical or electrical and magnetic resonance under certain conditions.
Composite composed of different materials, its inherent frequency is different from the inherent frequency of the original component, and when the structure of a part in the composite is changed, the inherent frequency of the composite also changes.
Using the resonance effect, it can change the intrinsic frequency of the composite material in accordance with the external operating frequency and avoid damage caused during operation. For the absorbing material, the composite frequency can also be adjusted according to the frequency characteristics of the foreign wavelength, and the purpose of absorbing foreign waves can be adjusted.
System Effect This is a complex effect of material, this effect is not very clear, but this effect has been found in the actual phenomenon
, for example, alternate The hardness of the laminated coating is greater than the hardness of the original single plating film and the linear mixing rate estimation value, indicating that the composition of the composite system can appear.
average effect, multiplial effect, parallel energy, induction effect, polyhydration effect, resonance effect, phase abrasion, system effects, etc., are subjects and important contents of composite materials research. This is also the basic theory of developing new composites, especially functional composites.
The maximum feature of composite is its designability.
Thus, under a given performance requirement, the use of environmental and economic conditions, design is designed from the selection pathway and process structure pathway.
For example, a mixture of a linear effect can be used to design a member that can be designed to be zero or close to zero.
Another as the XY plane is piezoelectric, the XZ plane is electrically luminescence, and the YZ plane pressure luminous composite is designed.
Latest: Ling
