Sandblasting aluminium sheet

[andyc0204]

Can anyone explain why aluminium sheet (2mm) deforms outwards from the centre (bulges) after sandblasting?

Cheers, Andyc (not a materials scientist)

 

[Hush]

This is just a guess. The sheet will have residual stresses caused from forming, kind of like surface tension. The sandblasting will reduce the residual stress on the one side leaving a stress imbalance and causing the sheet to bulge upwards.

 

[smcadman]

It deforms because there is a lot of friction. This friction causes heat which in turn causes the deformation.

Flores

 

[CoryPad]

Hush has it backwards - sand blasting causes residual stresses, which distorts the part. This effect also occurs during shot peening - the only difference is the size/mass/composition of the projectile.

 

[Hush]

I knew I was on the right track, just couldn't remember which way it worked.