隔振材料-橡胶

ELASTOMERS

高分子弹性体（橡胶）

ü Advantages(优点):

•  Provide effective control of dynamic forces.有效控制动态力下的变形。

• Able to undergo rapid cyclic deformations over a range of frequencies. 阻尼小，响应迅速。

•  Infinite shapes are possible可设计成任意形状.

•  Inherent properties are flexibility, high elongation and a combination of resilience and damping.具有弹性和阻尼特性。

ü Disadvantages(缺点):

• Attacked by certain environments.对环境（温度、化学物质）比较敏感

Properties(特点)

• Elastomeric isolators are always stiffer under dynamic conditions (shock and vibration) than for static conditions.动刚度＞静刚度

• Typical dynamic-to-static stiffness ratios are 1.3 - 1.7 : 1.动静刚度比

• As dynamic modulus is a function of frequency and strain, the dynamic-  to-static stiffness ratio is also a function of these parameters.动刚度与频 率、预载、振幅有关。

Properties(特点)

•  Hardness(硬度):

The resistance to indentation. Measured in Shore A durometer, scaled from 20 to

95. Practical duro range for isolators is 35 to 75.

硬度是橡胶材料抗压痕或抵抗硬物入侵表面的能力，通常用邵氏硬度计测量，材料

硬度范围SHA20~SHA95。通常隔振器的硬度范围SHA35~SHA75.

•  Modulus of Elasticity(弹性模量):

Ratio of unit stress to corresponding unit strain in tension, compression or shear.

Poisson’s ratio ~ 0.5, so elastomers are considered practically incompressible.

弹性模量是单位应力与应变的比值。泊松比≈0.5，橡胶一般认为是不可压缩的材料。

Properties(特点)

•  Hysteresis(迟滞性):

The difference between the amount of energy required for deformation and the

amount of energy recovered upon unloading. 加载与卸载所需能量的差异

•  Creep(蠕变):

Increasing deformation without accompanying increasing load that occurs over time. 在一定时间、 一定载荷下橡胶材料所发生的塑性变形。任何材料都有一定的蠕变特性。

蠕变系数

• Dielectric strength(绝缘性)

Elastomers have anelectrical resistance which varies according to their composition, hardness.

橡胶材料具有一定的绝缘性，绝缘强度与成分、硬度有关。

NR(天然橡胶)

  Hardness 45      1013      Ohm×cm²/cm(体积绝缘电阻)

  Hardness 75      104          Ohm×cm²/cm(体积绝缘电阻)

We have also developed special elastomers which can have a dielectric strength greater than 2000 Volts for 1 minute.

• Temperature Sensitivity（温度敏感性） :

Effects of high and low temperature compared to ‘room’ temperature on

modulus and damping characteristics.橡胶材料对高低温较敏感。

• Fluid Exposure（液体腐蚀）:

Effects of fluids (fuels, chemicals, etc.) on the performance of elastomer

compounds燃料、化学溶剂对橡胶材料性能有影响。

Natural rubber NR(天然橡胶NR)

• Advantages(优点):

Low cost, excellent bond, high tensile and tear strength, high fatigue life.

成本低，粘接性好，弹性好，伸长率高，撕裂强度高，疲劳性好。

•    Disadvantages（缺点） :

Moderate low temperature performance, poor fuel/oil/solvent resistance. Poor heat

resistance. Low damping.

不耐燃料、石油、化学溶剂，耐热性差，阻尼小。

Neoprene CR(氯丁橡胶CR)

• Advantages(优点):

Oil and moderate chemical resistant, excellent bond, good physical properties.

耐油，耐燃，耐氧化，耐臭氧，粘接性好，综合物理性能好。

•    Disadvantages（缺点） :

Poor low temperature performance.  Low damping.

耐寒性差，阻尼小。

Silicone Si(硅橡胶Si)

• Advantages(优点):

High damping, excellent temperature performance -73℃~ 232℃ .  Excellent

resistance to weather and ozone.

阻尼大，耐温性好，耐候性好，耐臭氧，绝缘性好。

• Disadvantages（缺点）:

Can be difficult to bond, low physical properties, low fuel resistance, high cost.

粘接性差，综合物理性能差，耐燃性差，成本高。

Properties of common rubber(常见橡胶特性)