Plasma in blown bulb

[bernardgreen]

This morning a 60 watt incandescent golf ball lamp blew with a vivid blue-white flash when switched on. It took out the 6 amp MCB protecting the circuit.

Part of the filament detached and has attached itself firmly to the glass. A powerful magnifying glass enables one to see very small pock marks on the inside of the glass, probably splatter of molten metal and that the end of the fragment of filament is fused into the surface of the glass.

That filament must have been extremely hot when it touched the glass to have melted the surface enough to hold the filament.

 

[Jackrae]

Literally white hot, that's what makes it incandesce

 

[bernardgreen]

Literally white hot, that's what makes it incandesce

I agree with that but the fact that it was still hot enough to ( apparently ) melt glass after the fall from stamen to the glass after the circuit was broken is the bit that surprised me. Unless there was enough plasma ( or similar ) discharge heating everything inside the envelope until the MCB operated.