Vanadium grain refinement

Vanadium is a grain refiner in the weld metal. It forms fine carbides and nitrides that slow grain growth during cooling. This makes the weld tougher and stronger. But you have to be careful with the amount. Too much vanadium makes the weld hard and brittle and increases the risk of cracking. Too little does nothing. The right dosage is usually on the filler packaging, stick to that. The cooling time is the decisive factor. If you cool too fast, you get nothing from the grain refinement. With normal steel welding with standard parameters, that usually works out on its own.