The function of welding consumables and it's usability

Consumables

Materials used in the welding process, mainly used for metal deposition or metal protection are defined as consumable.

These materials may differ in different welding processes. These materials can be classified on the basis of welding Processes, here we will classify them based on their use.

Consumables,

Filler metals:

Filler metal is an integral part of the weld, used to assist in filling the gap of the weld pool. usually, filler metals are available in the form of wire/rod, called filler were of filler rod .filler wires are available in a variety and size as per welding base material's chemical composition. Filler wire is used in several welding processes. in some welding processes, flux is also required due to avoid atmospheric contamination of the molten weld pool.

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Consumables,

Fluxes:

When the metal is heated/melted in the air during welding, oxygen from the air reacts with the metal to form oxides, it may cause poor weld quality. In some cases, making welding impossible. To avoid this difficulty, the flux employed during welding. Flux is a material used to prevent oxides and other undesirable substances.

How it works

The fluxes are fusible but nonmetallic and chemically react with oxygen/oxides during welding and slag is formed that floats to the top of the molten puddle and cover it, by this way keeps out the atmospheric gasses. Fluxes are available in all forms like liquid, paste, and powder.

Fluxes have used either direction of the surface of the melted weld metal or in the form of flux-covered electrodes.

Fluxes are used with many base metals like,

High Carbon steel melting point 1350 degree centigrade
3%Nickel steel melting point 1450 "
Stainless steel(Decay resistant) m.point 1440 "
Super silicon (cast iron) melting point 1147 "
Copper silver alloys melting point 1068 "

Nickel bronze melting point 910 "

5%Aluminium alloys melting point 635 "

Consumables,

Inert Gases:

Inert gas is used as a shielding gas to avoid atmospheric contamination of the molten weld pool it may be classified as follows:

Argon
Helium
Argon-helium mixture
Argon-hydrogen mixture
Argon-oxygen mixture

Carbon dioxide(CO2) is also used as a shielding gas in MIG welding, in this process CO2 being an active gas that is why this process called metal active gas (MAG)welding also.

When using CO2 as a shielding gas, the filler wire must contain deoxidizers such as silicon and manganese that readily react with the oxygen and prevent it from reacting with the weld metal.