白炽灯的制造过程是怎么被抽成真空的?

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白炽灯的制造过程是怎么被抽成真空的?
白炽灯的制造过程是怎么被抽成真空的?

白炽灯的制造过程是怎么被抽成真空的?
白炽灯里面不是真空.下面这段话来自wikipedia:
One of the problems of the standard electric light bulb is evaporation of the filament.Small variations in resistivity along the filament cause "hot spots" to form at points of higher resistivity;[32] a variation of diameter of only 1% will cause a 25% reduction in service life.[31] The hot spots evaporate faster than the rest of the filament,increasing resistance at that point—a positive feedback that ends in the familiar tiny gap in an otherwise healthy-looking filament.Irving Langmuir found that an inert gas,instead of vacuum,would retard evaporation.General service incandescent light bulbs over about 25 watts in rating are now filled with a mixture of mostly argon and some nitrogen,[52] or sometimes krypton.[53] Xenon gas,much more expensive,is used occasionally in small bulbs,such as those for flashlights..
帮你翻译一下:
普通白炽灯的一大问题是灯丝的气化.灯丝上局域电阻的小小的不均匀,亦会诱发高局域电阻处的“高温点”:灯丝直径哪怕有%1不均匀,也会因起%25的寿命缩减.高温点比其它地方气化快,这样高温点的局域电阻会越来越高(按:由于此处直径变小的更快.这里的resistivity 应该指的是一维电阻率,与物理上常用的3d电阻率不同.所以我翻译成了局域电阻):这样就形成了一种正反馈效应,使得灯丝上产生许多小坑;而状况良好的灯丝上是没有这些坑的.Lagmuir发现具有化学惰性的气体(按:不一定是8族气体),反而比真空更能防止这种气化.目前使用的标称功率在25瓦以上的普通白炽灯,都充有氩气为主,氮气为辅的混合气体.有时候还会有氪.在尺寸较小的灯泡里,有时也会掺进成本高得多的氙:手电筒里的灯泡就是如此.

在制造时放入适量磷,密封,灯丝通电发热,使氧气被消耗掉。一般不抽真空,都是去除氧气或充入惰性气体,以防止钨丝被氧化,主要作用是保护钨丝,延长使用寿命。(钨丝在高温下会缓慢升华,所以白炽灯寿命并不长)

在真空机里机器安上的

工作人员用嘴把里面的空气抽出来的。