Какое влияние оказывает влажность рабочей среды на сварку электронагревательных колец из нержавеющей стали?

The humidity in the working environment has the following effects on the welding of stainless steel electric heating rings:
Affecting welding quality
Forming pores: In a high humidity environment, the air contains more moisture. During the welding process, moisture will decompose into hydrogen and oxygen. Hydrogen atoms can easily invade the weld metal, and pores will be formed when they are not able to escape in time during cooling. These pores will reduce the density of the weld, weaken the strength and sealing of the welded joint, and may cause leakage and other problems during the operation of the electric heating ring.
Crack formation: After hydrogen atoms enter the weld metal, the toughness of the weld metal will decrease, the brittleness will increase, and cold cracks will be easily caused. Especially when welding high-strength stainless steel, the sensitivity of hydrogen-induced cracks caused by humidity is higher. The presence of cracks will seriously reduce the reliability of the stainless steel electric heating ring, and may even cause it to break during operation, affecting the normal operation of the equipment.
Reducing the performance of the welded joint
Degradation of mechanical properties: Defects such as pores and cracks caused by humidity will reduce the effective bearing area of ​​the welded joint, and stress concentration will easily occur at these defects when subjected to force, thereby reducing the strength, toughness and fatigue performance of the welded joint. For example, in a stainless steel electric heating ring subjected to cyclic loads, the reduction in fatigue performance of the welded joint may lead to premature fatigue failure and shorten the service life of the electric heating ring.
Reduced corrosion resistance: A high humidity environment will easily form a water film on the weld surface, and the dissolved oxygen and other impurities in the water will react chemically with the weld metal to accelerate the corrosion of the weld. Moreover, defects such as pores and cracks will destroy the passivation film on the weld surface, exposing the metal inside the weld to the corrosive medium, further reducing the corrosion resistance of the welded joint. When the electric heating ring works in a corrosive environment, the reduction in corrosion resistance of the welded joint may cause it to be corroded and damaged prematurely, affecting the normal use of the electric heating ring.
Impact on welding process
Arc stability: When the humidity is high, water vapor in the air will affect the stability of the arc. Water vapor will change the degree of gas ionization in the arc, resulting in fluctuations in the arc voltage and unstable arc burning. This will make it difficult to control the molten pool during welding, affect the forming quality of the weld, and cause defects such as uneven weld width, uneven height, and undercut, reducing the appearance quality and welding accuracy of the stainless steel electric heating ring.
Welding spatter: High humidity may increase the generation of welding spatter. On the one hand, the hydrogen produced by the decomposition of water vapor will change the surface tension and transition morphology of the molten droplet, making the molten droplet transition unstable and prone to spatter; on the other hand, arc instability will also cause fluctuations in welding current and voltage, which will in turn cause increased spatter. Welding spatter will not only waste welding materials, but also contaminate the surface of the weldment, increasing the difficulty of subsequent cleaning work.
In order to reduce the impact of humidity on the welding of stainless steel electric heating rings, measures such as controlling the ambient humidity, drying the welding materials, and improving the stability of the welding process parameters can be taken to ensure the welding quality and the performance of the electric heating ring.