why cookware does not melt down
On stove supllied with butane gas which has a flame temperature of 1970°C?
http://www.engineeringtoolbox.com/flame-temperatures-gases-d_422.html
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$\begingroup$ Why do you think cookware or even the oven is close to the flame temperature? $\endgroup$ – Greg Mar 30 '17 at 13:57
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$\begingroup$ You can solder very easily, domestic water pipes for example, but if there is any water in them this is simply impossible, the water conducts the heat away very effectively. Its the same in pans. $\endgroup$ – porphyrin Mar 30 '17 at 15:53
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$\begingroup$ This is adiabatic flame temperature - I guess you didn't check the link under table. You can't get such temp. in practice, as it won't burn adiabatically. $\endgroup$ – Mithoron Mar 30 '17 at 22:49
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The answer is that cookware transfers the energy from the flame into whatever is being cooked. For instance a pot of boiling water will stay unmelted until all the water has evaporated, after which the pot will start heating up towards the melting point of the metal it is made from.
This is called heat conductance and is used in both cookware and liquid bi-propellant rocket engines (which burn closer to 3000°C). In fact some rocket engines have been made from aluminium with a melting point as low as ~460°C depending on which alloy is used.
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$\begingroup$ so the cookware dissipates heat faster than the heating, let say I have steel or stainless steel pot and I want reach 1000 how doing that? $\endgroup$ – kyo adam Mar 31 '17 at 15:03
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$\begingroup$ Well, you have two options. You can keep the heat from dissipating (e.g., something like a furnace or kiln) or you can increase the thermal input (e.g., bigger flames like in a furnace). This is why metals are melted down in furnaces. $\endgroup$ – Zhe Mar 31 '17 at 17:25
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$\begingroup$ @Zhe good advise thank you, does pressure help to ? $\endgroup$ – kyo adam Mar 31 '17 at 17:32
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Cookware has a large surface area and radiates heat. Also conducts heat to water or food it is in contact with. You reach a steady state at some temperature that is less than the melting point.
If you used a small piece of metal, you might get some melting. For example, if you put a post-1983 penny on your burner, you can probably metal the zinc inside to form a brass alloy.
