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When the two materials are in contact and separation, the polarity and size of the charge are represented by the position of the material in the friction series. The friction series shows the charge generated on the various materials. When the two materials are in contact and separated, a positive charge near the top of the series and the other is a negative charge. The material that is further separated on the table usually produces a higher charge that is closer together. However, these tables can only be used as general guidelines, since many variables are not well controlled to ensure repeatability. Typical series of triboelectric motors are shown in Table 2.
The material that prevents or restricts the flow of electrons through its surface or through its volume is called an insulator. The insulator has a very high resistance, and the insulating material is defined as a "surface resistance or volume resistance equal to or greater than 1 x 1011 ohm material". A considerable amount of charge may be generated on the surface of the insulator. Since the insulating material is not easy to allow electron flow, the positive charge and the negative charge can simultaneously reside on the insulating surface, although at different positions. The excess electrons at the negative charge point may be sufficient to satisfy the presence of electrons with positive charges. However, electrons can not easily flow through the surface of the insulating material, and the two charges may remain in place for a long period of time.
The conductive material has a low resistance, and the conductive material tends to flow through its surface or through its volume. The conductive material has a low resistance, each glossy ESD ADV1.0 is less than 1 x 104 ohm (surface resistance) and 1 x 104 ohm resistor). When the conductive material is charged, the charge (i.e., the insufficient or excess of electrons) will be distributed evenly over the surface of the material. If the charged conductive material is in contact with another conductive material, the electrons will be easily shared between the materials. If the second conductor is connected to the ground of the AC device or any other ground, the electron will flow to the ground, the excess charge on the conductor Will be neutralized.
The electrostatic charge can be frictionally fabricated on the conductor, which is the same as the electrostatic charge generated on the insulator. As long as the conductor is isolated from other conductors or ground, the electrostatic charge will remain on the conductor. If the conductor is grounded, charging will be easily grounded. Alternatively, if the charged conductor contacts another conductor, the charge will flow between the two conductors.
Static Dissipative Materials
Static dissipative materials have an electrical resistance between insulative and conductive materials (1 × 104 <1 × 1011 ohms surface or volume resistance). There can be electron flow across or through the dissipative material, but it is controlled by the surface resistance or volume resistance Of the material
As the the other other types of materials, charge can be generated triboelectrically on a static dissipative material. However, like the conductive material, the static dissipative material will allow the transfer of charge to ground or other conductive objects. The transfer of charge from a Static dissipative material will concurted by longer than from a conductive material of equivalent size. Charge transfers from static disslative materials are significantly faster than from insulators, and slower than from conductive material.
The charging material also has an electrostatic field and a force line associated therewith. The conductive object introduced near the electric field will be referred to as the induction process polarization. Figure 3. The negative electric field will repel the electrons on the surface of the conductive article exposed to the field. The positive electric field will attract electrons close to the surface, so that other areas are positively charged. The actual costs on the items will not be biased. However, if the article is conductive or dissipative and is connected to the ground at the time of polarization, the charge will flow or be grounded due to charge imbalance. If the electrostatic field is removed and the ground contact is disconnected, the charge will remain on the item. If the nonconductive object enters the electric field, the electric dipole will tend to have a surface charge relative to the field. Non-conductor (insulating material) can not be charged by induction.
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