Maintaining the structural integrity of welded joints over time is critical for the safety and longevity of metal structures. However, several challenges often arise, compromising their performance. One major issue is corrosion, especially in harsh environments where moisture or chemicals accelerate material degradation. Proper coating and material selection are essential to mitigate this.

Another common problem is fatigue cracking, caused by cyclic loading or vibrations. Over time, micro-cracks can propagate, leading to catastrophic failure. Regular inspections and stress-relief treatments help address this.

Residual stresses from the welding process also pose a threat, as they can distort the joint or create weak points. Post-weld heat treatment (PWHT) is often used to relieve these stresses. Additionally, poor weld quality—such as incomplete penetration or porosity—can weaken joints, emphasizing the need for skilled welding techniques and stringent quality control.

Lastly, thermal expansion and contraction due to temperature fluctuations may cause joint misalignment or cracking. Designing joints with flexibility in mind can prevent such issues. By understanding and addressing these challenges, engineers can ensure welded structures remain durable and reliable for years to come.