Need stress value of aluminium for project work

[Hakuyu]

TL;DR

Im not a physics student but I really need to prove that aluminium will not deform 10m underwater

Summary: I am not a physics student but I really need to prove that aluminium will not deform 10m underwater

Hi I am doing a project of a product which will sink underwater.
It will be a sealed cylindrical vessel, length 2m, width 1m, thickness 0.02m.
Aluminium 6061t will be used with a yield strength of 276MPa.
Pressure of water 10m underwater will be 99kPa.

If you can provide me with the stress value of aluminium please also provide me with your designation as I need to cite it with your approval.

Thank you so much !

 

[berkeman]

Summary: I am not a physics student but I really need to prove that aluminium will not deform 10m underwater

Summary: I am not a physics student but I really need to prove that aluminium will not deform 10m underwater

Hi I am doing a project of a product which will sink underwater.
It will be a sealed cylindrical vessel, length 2m, width 1m, thickness 0.02m.
Aluminium 6061t will be used with a yield strength of 276MPa.
Pressure of water 10m underwater will be 99kPa.

If you can provide me with the stress value of aluminium please also provide me with your designation as I need to cite it with your approval.

Thank you so much !

Is this for a school project? If so, which class?

If not, what is the overall project that you are working on? And what do you mean by "cite it with your approval"? Approval for whom?

 

[Dr.D]

Sorry to disappoint you, but there will be some deformation assuming that the pressure inside is different from that outside. Everything has some deformation under load.

 

[FEAnalyst]

In „Roark’s Formulas for Stress and Strain” book you can find formulas for stress in cylindrical pressure vessels subjected to external pressure. But I performed Finite Element Analysis assuming flat bottom and maximum von Mises stress result is about 40 MPa.

 

[Spinnor]

Using the above graph can I assume his aluminium vessel is good to about 4000m depth?

In „Roark’s Formulas for Stress and Strain” book you can find formulas for stress in cylindrical pressure vessels subjected to external pressure. But I performed Finite Element Analysis assuming flat bottom and maximum von Mises stress result is about 40 MPa.

 

[JBA]

Using the above graph can I assume his aluminium vessel is good to about 4000m depth?

Based upon the the flat end closure plate's above determined 40 MPa stress at the 10 m depth and the stated maximum allowed S yield of 276 MPa for the material, the maximum depth = 10 x 276/40 = 69 m without any safety factor.