Top 10 Tips to Prevent Fatigue Failure In Your Mechanical Parts

When working with machines or equipment we need to be aware that their parts and components are subjected to cyclic or variable loads that may lead to a failure due to fatigue.By definition, fatigue failure is termed as the tendency of a material to fracture due to progressive brittle cracking under repeating stress which is considerably below the normal strength. Although the fracture is of brittle type, still its time of appearance will depend upon the nature of stress on the material.

The manufacturing process, technology applied and materials are the key to preventing these problems. 

Fatigue failure may arise due to the following causes:-

• Presence of internal irregularities or discontinuities.
• Irregularities resulting from part machining processes themselves.
• Part geometry type. This will affect the speed at which cracks will propagate.
• Environment influence: thermal fatigue and corrosion fatigue.

Here are the 10 tips which will help prevent fatigue failure in the mechanical parts :-

1. First, it is necessary to keep in mind that any variation in part or mechanical component sections are special regions where stress will concentrate, which will affect their mechanical fatigue strength.

2.The geometry or the shape and size of the tool or component will also have its sweet share while sketching a probability where the fatigue fracture can occur. If there is an abrupt stop in the geometry or the design then that area will certainly attract more stress. This region will then be more prone to fatigue fracture. For example, if there is a design of a keyhole. Then this particular area will be more prone to the stress fracture.

3.The design also has a significant influence in fatigue failure. Any geometric discontinuity acts as a stress concentrator, and may become the point of origin of a crack due to fatigue. The sharper the discontinuity, the more severe the stress build-up.

4.Structural irregularities is also a big factor which would decide the magnitude of the stress. Hence ignoring this can be a big factor towards causing fatigue failure of the equipment. For example, if there is a shape which ends in a square will surely have more stress acting on it and will act as an initiator for fatigue failure.

5. The dimensions of the part also play a part; increasing their size results in a lower fatigue limit.

6.Carburizing and Nitriding Process: These are the process of surface hardening. In this process, the core material is exposed to carbon and nitrogen-rich atmosphere at high temperatures. Hence creating a layer of hard material over the surface. This protects the underlying surface to a greater degree.

7. Surface hardening via carburization and nitriding processes where a component is exposed to a carbon or nitrogen-rich atmosphere at high temperatures. This layer is usually 1mm deep and harder than the core’s material.

8.Tensile strength is also an important factor to be noted in order to prevent fatigue failure. If the tensile strength is of intermediate nature then the material will be more prone to failure.however having a proper compressive strength, on the other hand, protects the material.

9. An intermediate tensile stress worsens fatigue-related performance in metals since it widens the crack. Conversely, compression stress improves it.

10. Increase performance by means of residual compression stress on a thin surface layer. The overall effect is that the probability of crack nucleation and fatigue failure is reduced.