1. Too Low Hardness
As with any kind of heat treatment process, one of the most common quality issues that can arise when heat treating a bearing part is too low hardness, usually caused by insufficient heat treatment time and temperature. If the bearing part is below the specified hardness, it will not be able to stand up to the mechanical loads it was designed to bear and may eventually break off and cause further mechanical damage.
2. Too High Hardness
However, too much heat treatment of a bearing part can also be problematic, leading to a hardness that is too high. This can cause brittleness, making the bearing part more susceptible to fractures and cracks during use, again leading to further mechanical damage.
3. Temperature Inaccuracy
Another major cause of quality issues in heat treating bearing parts is temperature inaccuracy, which can lead to problems with both too low and too high hardness of the parts. If the accuracy of temperature is poor, it can lead to insufficient heat treatment time, making the bearing parts too soft, or a temperature that is too high that make them too hard.
4. Uneven Hardness
Uneven hardness of a bearing part is also a common quality issue in heat treatment processes. This can happen for a variety of reasons, such as improper heating of the part, mismatched chemical compositions, or failure to use appropriate cooling methods. Uneven hardness can cause brittle surfaces and potential metallurgical flaws leading to premature failure.
5. Decay
Inaccurate or inadequate heat treatment of a bearing part can also cause decay in the part, or signs of oxidation or chemical attack. This can severely weaken the bearing part and make it unsuitable for use.
6. Distortion
Heat treatment of bearing parts can also lead to distortion if the process is not done correctly. If the part is heated too quickly or too slowly it can cause warping, bending, or other unwanted structural deformations that must be corrected before it can be put into service.
7. Scaling
Scaling is yet another common quality issue in heat treatment of bearing parts that can be caused by improper temperature control. When parts are heat treated, they can become covered in a layer of scale, which must be removed before the part can be used.
8. Pitting
Pitting is another type of quality issue that can arise with heat treatment of bearing parts due to insufficient or inaccurate temperature control. Pitting can lead to wear and fatigue of the part, as well as premature failure in certain applications.
9. Cracks
Cracks are a common quality issue with heat treated bearing parts. This can occur due to inadequate heat treatment, or due to stresses produced during cooling. If left unchecked, these cracks can grow and weaken the bearing part, leading to premature failure.