材料的电导率和电阻率与温度的关系

阿司匹林

  电阻和电阻率的关系如下：R1 = R2 * [1 + a * (T1–T2)]
问题：25摄氏度，电阻率是2.706 x 10-8  a = 0.0043/ oC，请问20 oC时的电阻率是多少?
答案：R1 = R2 * [1 + a * (T1–T2)]
把下列参数带入上式：
            R2 = 2.706 x 10-8 ohm meters (measured resistivity at 25 oC)
            a = 0.0043/ oC
            T1 = 20 oC
            T2 = 25 oC
得到：
R1 = 2.706 x 10-8ohm meters * [1 + 0.0043/ oC * (20 oC – 25 oC)]
   = 2.648 x 10-8ohm meters
可以看出，温度越低，电阻率也就越低。或者说，温度越高，导体的导电性就越差，电阻就越大，通过相同电流时，损耗（一般导线材料是铜，因此也叫铜损）也就越大，这是在很多涉及到导线的设计时都需要考虑的问题。
Since conductivity is simply the inverse of resistivity, the temperature coefficient is the same for conductivity and the equation requires only slight modification. The equation becomes:
s1 = s2 / [1 + a * (T1–T2)]
Where: s1 = conductivity value adjusted to T1
            s2 = conductivity value known or measured at temperature T2
                  a = Temperature Coefficient
           T1 = Temperature at which conductivity value needs to be known
           T2 = Temperature at which known or measured value was obtained

Material       
Temperature Coefficient (/ oC)
Nickel         0.0059
Iron        0.0060
Molybdenum        0.0046
Tungsten        0.0044
Aluminum        0.0043
Copper         0.0040
Silver        0.0038
Platinum        0.0038
Gold        0.0037
Zinc        0.0038