molten glass temperature??

[Maggie]

Not sure if this topic goes here but I 'll give it a shot. When doing a demo in my daughters school last week (P5s were learning about materials) I was asked what temperature is the hot glass in the flame? Now don't want to be a dope but I don't know the exact answer to this.. 'What temperture is the molten glass?'
(Got more schools to demo to in a few weeks time and need to be prepared!)

p.s. second most popular question was 'how much does do they cost?' !

Maggie

[helbels]

According to Wikipedia, soda lime glass reaches it's liquidus temperature (which I'm assuming means melting!) at between 1000 degrees C and 1040 degrees C

[stuwaudby]

It starts to become workable over 700 DegreesC and will be quite "gloopy" over 800. Probably gets over 1000 when cooking to gravity shape.

[Maggie]

Thats good information, thanks!
Feel better armed to answer questions now!

[james M knox]

Liquidus is the temperature above which an alloy is completely molten.
In other words, when an alloy exceeds the liquidus temperature, there
are no solid phases present. The alloy is completely melted and
flowing.

Any Help?

JMKnox

[Redhotsal]

Actually there is no specific temperature - it's more of a range of temperatures - which depends a lot on the glass constituents. And of course it depends on the glass - so soda glass will melt at a lower temperature range than borosilicate. It's a bit of a "how long is a piece of string" question, really.
For "our" glass - Effetre, for example it will start to melt at 800 C but as has been said earlier it's not very specific. Tell the kids it's like chocolate - that doesn't melt at a specific temperature either. But you can eat chocloate and you can't eat glass (although some of the more obsessed on here have been known to lick their glass rods! )

[Hamilton Taylor]

I always say about 1000C - it's in the ballpark, and a nice big number which usually gets a 'wow'.
I then follow up with a rather lame joke about roasting chicken, which generally serves to drive 'em away, but it keeps me happy....

Sean

[ScarletLeonard]

I generally say that the flame is between 800-1000 Celsius. It was enough to keep year 6 happy last year.
That got a wow and was quickly followed by How many times have you burnt yourself?

[Donna@Rockin' Beads]

I always say about 1000C - it's in the ballpark, and a nice big number which usually gets a 'wow'.
I then follow up with a rather lame joke about roasting chicken, which generally serves to drive 'em away, but it keeps me happy....

Sean

[tomcat]

It's a bit of a "how long is a piece of string" question, really.

actually - thats an easy one to answer - its twice as long as from the middle to one end  - not going to comment on the glass bit as i am a newbie and can but agree with the answers already given 

[Pat from Canvey]

I set my big ceramic kiln at 930 deg C for pot melts. If the glass is not flowing to my liking, I raise the temp by 20 degrees.
http://kiloalphatango.com/my_version_of_the_multi_coloured_dreamcoat