Letter 37085

Need 6061 T6 to retain as much heat as possible [Ohio] 

+++++

Ok heres the deal. I have to design a new oven for a costumers oven. The machine runs 300 degrees C, 24 hours a day, 7 days a week. The oven is inside a machine, I need it to retain as much heat as possible. Will anodizing help or hinder my project?

Matt Spicer
- Fairfield, Ohio, USA

The anodize may crack if cycled to that temp. Decreasing thermoconductivity of aluminum is a waste of effort unless it a very unusual problem. Think insulation or vacuum or trapped air space.

James Watts
- FL

Essentially, if I can recall reading this correctly. In terms of heat retention. Anodizing will insulate and retain more heat than a non-anodized coating. My knowledge of such is in heatsinks and their effects in PC applications. I know that in actuality an anodized heatsink will extract heat at a slower rate than a non-anodized one. So in reverse, in your application it would help.

To what extent, I can't tell you exactly. I can tell you in a PC application, a 1-2C variance in a roughly 80W-100W processor is noted. Thats minor in the real world, but its significant in certain situations. If anodizing insulated and made a 10-12C differential, I'd call it considerable.

My suggestion, take the thickness of the plate you were going to use, cut em 12 x 12, anodize one, don't anodize the other. Put temp probes that are capable of withstanding those kinds of temps on to the parts, and heat them up. Pull them out and measure the differential in temperature loss. (You can probably also achieve this at timed intervals with one of those fancy laser light temp probes) Whichever loses the heat faster, is going to be the lesser desired application for you. Thats the only true way I can think of to test this theory. You can take my, or anyone elses word but till you put the rubber to the pavement so to speak, you can't validate anything.

Matthew Stiltner
- Toledo, OH

The thermal coefficient of expansion of aluminum oxide is 0.2 that of the raw aluminum. AT 300 C the raw aluminum will expand 5 X that of the oxide and the oxide wilil fall off.

Robert H Probert Robert H Probert Technical Services Garner, NC, USA Editor's note:        Mr. Probert is the    author of Aluminum How-To

Hardcoat anodize is widely used on cookware and commercial pizza pans for it's wear resistance and improved heat distribution. In these applications, it is exposed to thousands of thermal cycles and does not "fall" off.

Chris Jurey Luke Engineering & Mfg. Co. Inc. Wadsworth, OH

I want to answer or follow-up on this subject publicly (in non-commercial fashion).

 

My company is a supporting advertiser at finishing.com and we want the contact information to reach the inquirer privately.

 

I want to post a new question or inquiry of my own on a different subject.