Difficulties and solutions for stainless steel welding!

When using traditional welding methods, we often need some help. Fortunately, we have laser welding technology that can solve these problems. Next, we will highlight these difficulties and show how laser welding can alleviate them.

Problem 1: Heat-Affected Zone (HAZ)

The HAZ can sometimes change material properties, increasing susceptibility to corrosion and structural weaknesses. When performing arc welding, the weld area typically experiences more of a HAZ. In this case, laser welding produces the smallest HAZ. Its focused laser beam melts the metal precisely at the weld point. The concentrated energy input typically reduces the HAZ.

Problem 2: Corrosion

Traditional welding often compromises the corrosion resistance of stainless steel. Stainless steel is susceptible to corrosion from contamination during the welding process. Laser welding minimizes these risks by using a concentrated and controlled heat source. Therefore, it reduces the overall thermal impact on stainless steel.

Problem 3: Thermal Deformation

Thermal deformation refers to the deformation or change in the shape of the material caused by heat. This often occurs in traditional welding, especially on thin stainless steel plates or pipes. Laser welding can handle all thicknesses without thermal deformation. Laser welding is a welding technology suitable for metals with smaller thicknesses.

Issue 4: Manual labor

Traditional welding methods usually require manual labor. It also requires skilled labor to perform complex tasks. Ultimately, it leads to higher production time and investment costs. In contrast, laser welding has revolutionized this aspect. It has introduced automation and precision. The equipment is convenient, lightweight and easy to carry, suitable for handheld laser welding.

Issue 5: Precision

Traditional welding methods are undoubtedly less precise than laser welding. It uses a focused laser beam to precisely melt the welding point. Therefore, it produces minimal heat-affected zones and thermal deformation. Therefore, laser welding is widely favored for its welding precision.

Issue 6: Environmental risks

Traditional welding methods often emit harmful fumes, gases and particulate matter. Technically, it is harmful to the environment. The release of metal oxides and welding fumes pollutes the air and water. In contrast, laser welding provides a cleaner and more environmentally friendly option.

Behavior of Laser Welding on Different Stainless Steel Materials

Stainless steel can be of various types. The composition of these types varies with each variant. Therefore, laser welding behaves differently in each type as well.

Austenitic stainless steels are known for their high chromium and nickel content. 300 series stainless steels are typical austenitic stainless steels. They are used in applications that require high corrosion resistance and high temperature resistance. Well, both pulsed and continuous types of laser welding are suitable for this type of SS. Nevertheless, high heat input may cause precipitation of chromium carbides.

Ferritic stainless steels usually contain some 400 series stainless steels. They do not contain nickel. Moreover, their laser weldability is not as good as austenitic stainless steels. As a result, it reduces the hardness of the joint by forming coarse grains in the HAZ area. On the other hand, the HAZ part can have a higher hardness. This means that this area is more susceptible to embrittlement.

Martensitic 400 series stainless steels are more difficult to laser weld than the other two types mentioned above. They have a high carbon martensitic grade. Usually, it ranges over 0.15%. After welding, it may result in a high hardness in the HAZ, resulting in a high brittleness. Therefore, experts always preheat these stainless steels to 650-750°C before welding. It reduces the brittleness of the heat-affected zone.

Duplex stainless steels are usually a combination of austenitic and ferritic stainless steels. You know they are known for their two-phase microstructure. It contains mainly chromium, nickel and molybdenum. They are usually suitable for laser welding and achieve good results.

Related product links

Fiber Laser Welding Machine