Stainless steel wires, Matt finish versus bright finish
A huge number of mills are daily drawing stainless steel wires and not one wire is the same. Some of them look very similar but below the surface there are many things that affects the quality. Some wires have strength of more than 1500 MPa and some wires only have 600 MPa. But why is this so important?
During wire feeding through the welding gun the wire surface is constantly sliding against the liner and is pushed through the contact Tip. This liner can be made from steel, but some welders prefer a Teflon liner and believe that this results in less friction. Partly this is correct for most bright finished wires, but a matt finished wire has usually a rougher surface that could create even more friction.
During drawing each type of stainless-steel welding wire must undergo a heat treatment that fits to the alloy and here is a lot of know how required from the drawing company, If the heat treatment is applied to late in the process the wire surface can show small cracks and can hide contamination in further drawing, so it is very important that these production steps are followed correctly.
MATT
Each drawing company has its own production formula and must be very well followed to always obtain the same quality, drawing the wire through the dies can be done wet or dry and with a number of different lubricants, chemicals, soaps or dry mix. All these variations have influence on the final surface properties of the wire and sometime we hear welders say they prefer the bright wire whereas other welders prefer the matt wire but please note that this is not covering everything.
when using oil types of lubricant during drawing the cleaning process in between becomes more important and overall the wire must be cleaned during the drawing process several times.
BRIGHT
To obtain perfect arc properties in short circuit and spray arc the wire needs to be extremely clean to obtain a bright weld seam and a steady arc. CEWELD® stainless steel wires do not have any drawing residues and are therefore even suitable for cold and hot-wire Tig welding.