# Need stress value of aluminium for project work

• Hakuyu
In summary, the conversation discusses the use of aluminium in a sealed cylindrical vessel that will be submerged 10m underwater. The yield strength of the aluminium is 276MPa and the pressure at 10m depth is 99kPa. The conversation mentions using Roark's Formulas for Stress and Strain to determine the stress in the cylindrical vessel, and the maximum von Mises stress is found to be 40MPa. The conversation also touches on the depth limit for the aluminium vessel, which is calculated to be 69m without any safety factor.
Hakuyu
TL;DR Summary
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 !

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Hakuyu said:
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?

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.

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?

FEAnalyst said:
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 said:
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.

Spinnor

## 1. What is the stress value of aluminium?

The stress value of aluminium varies depending on the specific alloy and manufacturing process. It is typically measured in megapascals (MPa) or pounds per square inch (psi). In general, the stress value of aluminium ranges from 100 MPa to 500 MPa.

## 2. How is the stress value of aluminium determined?

The stress value of aluminium is determined through testing and analysis. This involves subjecting the aluminium to various levels of stress and measuring the resulting strain. The data is then used to calculate the stress value using mathematical equations and formulas.

## 3. Why is the stress value of aluminium important in project work?

The stress value of aluminium is important in project work because it helps determine the structural integrity and strength of the material. It is crucial to know the stress value in order to ensure that the aluminium can withstand the expected load and perform as intended in the project.

## 4. Does the stress value of aluminium change over time?

The stress value of aluminium can change over time due to factors such as corrosion, temperature changes, and fatigue. It is important to consider these potential changes when using aluminium in a project and to regularly monitor the stress value to ensure the material is still suitable for its intended use.

## 5. Where can I find the stress value of a specific aluminium alloy?

The stress value of a specific aluminium alloy can be found in technical data sheets provided by the manufacturer or through testing and analysis. It is important to use the stress value for the exact alloy and manufacturing process being used in the project to ensure accuracy.