Permissible Stress and its Definition

Definition: Permissible stress is the maximum stress a material can withstand without failing under a given loading condition. It is also known as Working Stress.

Factors affecting Permissible Stress

There are several factors that affect the permissible stress of a material. Some of them are:

- Type of material
- Temperature
- Loading condition
- Duration of loading
- Corrosion

Permissible Stress and Working Stress

Permissible stress and working stress are often used interchangeably, but they are not the same thing. Working stress is the stress that is used in the design of a structure or machine component. It is calculated by dividing the permissible stress by a factor of safety.

The factor of safety is a multiplier that is used to ensure that the structure or component can withstand loads that are greater than the expected working load. The factor of safety is typically between 1.5 and 2.5, depending on the application.

Difference between Permissible Stress and Ultimate Stress

Permissible stress and ultimate stress are also not the same thing. Ultimate stress is the maximum stress a material can withstand before it fails under any loading condition. Permissible stress is always less than ultimate stress.

Conclusion

In conclusion, permissible stress is the maximum stress a material can withstand without failing under a given loading condition. It is also known as working stress and is used in the design of structures and machine components. Permissible stress is affected by several factors, including the type of material, temperature, loading condition, duration of loading, and corrosion. It is different from ultimate stress, which is the maximum stress a material can withstand before it fails under any loading condition.