Resistance welding is an ideal method to fuse two pieces of stainless steel wire and create a strong bond. This kind of welding does not require a separate welding material. When done in the right manner, you can join small pieces of metal with resistance welding without a fault and effortlessly.
But, you should know that it is a tricky welding technique. If you fail to do it correctly, it could lead to a series of defects, which manufacturers need to steer clear of.
Let’s take a look at some of the resistance welding defects:
- Spattering
The processes that depend on a separate substance to serve the purpose of a bonding agent, they face a common issue of weld spatters. With resistance welding, on the other hand, it is a sign of defective welding. One of the main causes of spattering is using a very strong current to form the weld. The loss of material during the welding process weakens the strength of the finished product.
- Cracks
Where on one hand, using too much pressure reduces weld heat, too little pressure could cause issues. When the weld electrodes are unable to put enough pressure at the weld site, the joint could show signs of cracking or become porous.
Also, cracks at the weld area point towards the low tensile strength of the weld as the two metal pieces couldn’t join properly.
- Dented Surfaces
Precise control on pressure is required for consistent spot welds and join the metal surfaces efficiently. Excessive pressures lessen the resistance to electrical current that keeps the metal from arriving at the needed welding temperature.
Heavy indentations found during the inspection of a resistance-welded object means that the metal parts were joined too tightly and points toward a weak weld.
- Metal seeping from the joint
Expulsion of the metal from the area where two pieces of metal are joined is another problem in resistance welding and indicates various problems with the weld like contamination of the surface, excessive use of current, insufficient weld pressure, and mistiming of weld.
Molten metal coming from under the weld points to a weak weld. There are many other signs of poor welding that impact the look and quality of the finished product. Take the example of wire baskets. There could be some physically distorted parts or severe scorch marks, but you can see these spots right away compared to the others mentioned above.
- Uneven Spot Weld Marks
A well-executed resistance spot weld mark should have a perfectly round shape or should adapt to the welding head’s shape used to join the two pieces of metal.
Uneven shapes indicate that the weld has imperfections, which could be anything from the presence of foreign pollutants at the weld site to misaligned electrodes. There could be many reasons. This leads to the creation of a weaker weld that could easily break when put under pressure.
So, pay attention to the above-mentioned defects of resistance welding. Ensure that your resistance welding finished products are free from them. Also, don’t remember to don the protective gear and welding helmet while carrying out any welding activity. To find the best variety of welding helmets, visit Welding Corner.