Mic 6 Aluminun Plate Warping Away from Hot Plate

This is normal. The plate is expanding more on the hot side than the cool side.

Keep the temperature constant on both sides and no warp.

Aluminum has a high coefficient of thermal expansion so the effect is magnified.

Machining a series of grooves might help, but it will reduce the themal conductivity of the aluminum.

You might be able to straighten them by exposing the "other' side to the hot plate and warping it back the other way. This could get tricky.

Welcome to CR4.

Well - the choice to use this quality of Al. plates is unusual!!

(not recommended by ALCOA)

Anyway would you try to isolate this plates underneath the molds,or;plate's bottoms?

I would try INSTEAD thinner (1/8") rolled plates,AA 6061-t651-comparatively low price

(what is the mold's weight?)

From the ALCOA product data sheet:

MIC6 can be repetitively cycled through a thermal exposure without affecting or altering the physical properties of the plate. Thermal treatments during each cycle can range from 250 to 600 °F (120 to 315 °C). Full support under the plate during the thermal cycle is recommended - the thinner the plate, the more important this consideration becomes.

It further indicates it is a proper selection for heating and cooling platens.

Do you have a different datasheet for MIC6?

I don't know if this would work, but you may be able to put your plates in a standard oven, set at 450°, on a flat surface. They might lay down. I don't think it would hurt to try. You may have to devise a way to put a little weight on them. Allow them to cool slowly in the oven before removing.

Lyn's right on keeping the heating uniform to prevent future warpage.

You can machine hemispherical depressions into the top surface of the aluminum plate so as the plate bows, the top surface becomes flat.

Thanks for everyone's replies.

We are going to cut the reliefs in one plate and try that. We may try heating and applying weight , if I can get access to an oven.

This on my large list of things to do , so it may be a little while before I can say what worked, but I will let you know the results.

Thanks again you guys are my hero's ---- Bill

I milled a 1/16" x 12" slot accross the bottom of the plate and this seemed to worsen the bow . ( It is bowing away from heat with a 5 lb mold on top)

We don't have a free oven to try heating the plate to 450 degrees yet. But will do it soon.

My Boss wants to take a new plate and waffle the bottom hoping this will strengthen it and make it more rigid.

Any comments on this idea?

Thanks Bill