When people work excessively, they often feel fatigued, indicating a need for rest. Overexertion can pose serious risks to one’s life. But have you ever heard of metals experiencing a phenomenon known as “fatigue” after prolonged use?
Indeed, there are instances where a ship unexpectedly breaks in half during its journey; an airplane carrying numerous passengers suddenly loses its tail wing, leading to immediate disaster; a train engine derails, or a bridge and machinery components suddenly fail. Many of these incidents are caused by the “fatigue” of metals.
Metals exhibit fatigue, leading to cracks and breakage when exceeding their load capacity.
Why do metals also experience “fatigue”? Metals are known for their high hardness; however, the loads exerted on their structure and components are often quite significant. If this load continues to be applied thousands or even millions of times, internal structures will begin to crack. The impact of the load significantly reduces the hardness of the metal.
The phenomenon of metal “fatigue” occurs until it surpasses the metal’s capacity to withstand tensile forces and impact loads, ultimately resulting in cracks and breakage. For example, when you don’t have a pair of pliers at hand and want to cut a small steel wire, you might bend it back and forth at the cutting point, causing the wire to break. This is an example of “fatigue” in steel due to the impact of a load.
Metal “fatigue” can include: “fatigue due to friction,” “fatigue due to high temperatures,” “fatigue due to sub-zero temperatures,” and “fatigue due to noise,” among others. The phenomenon of “fatigue” is very likely to occur in components with varying cross-sections, such as parts of airplanes and ships; machinery connected by rivets or welds, such as an airplane’s tail wing, axles, and junctions of rails, etc.
Not only metals but other materials like rubber, plastic, and concrete can also exhibit “fatigue,” posing hidden risks of disaster.
To prevent hazards caused by material “fatigue,” you should take the following measures:
First, minimize weak points in detailed components, such as holes, grooves, and cut edges, as fatigue cracks often originate in those areas.
Second, ensure that the surfaces of the components are smooth and free from corrosion and rust, as rough surfaces and corroded materials are more likely to develop cracks.
Third, treat the surfaces of the components, for example, by compressing the surface, using sandblasting, or applying high-pressure water jets to the surface. This will make it difficult for small cracks to form in the components.
