1.电阻特性 Resistance property
 硅钼棒-二硅化钼电热元件的电阻率随着温度的升高而迅速增加。在正常操作情况下，元件电阻一般不随使用时间的长短而变化。因此，新旧元件可以混合作用。
The resistivity of element rapidly rises as the temperature rises，under normal operating conditions ，generally the element resistance doesn't change with the service time changing.So the old and new elements can be used mixed.
2.表面负荷 Surface load
 根据炉子的结构、气氛和温度正确地选择元件的表面负荷是达到最好元件寿命的关键。右图示出了元件辐射在不受阻碍情况下的炉温、元件温度与表面负荷间的关系，阴影部分为常用的表面负荷－温度范围。
The key factor to the optimum servivice life of the element is to select the surface load of the element correctly according to the furnace construction，atmosphere and temperature.Right figure shows the relation between the furnace and the element surface load under the condition that the element radiation isn't obstructed.The shadow part in the figure shows the surface load-temperature range in common use.The figure still shows the reference current.
推荐的表面负荷 Recommend surface load:
炉温(℃）
Furnace Temp
|
1400
|
1500
|
1600
|
1650
|
1700
|
|
发热部表面负荷Surface load of hot zone(W/cm2)
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<18
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<15
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<12
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<10
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<8
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| 