Differences between Welding, Soldering and Brazing

Welding, Soldering and Brazing are the metal joining process. Each type of joining process has its ownsignificance. Type of joining process to be used for joining two parts depends on many factors. In this article Ihave covered the differences between the joining processes welding, soldering and brazing.

S.No Welding Soldering Brazing

1 Welding joints are strongest jointsused to bear the load. Strength ofthe welded portion of joint is usuallymore than the strength of basemetal.

Soldering joints are weakestjoints out of three. Not meantto bear the load. Use to makeelectrical contacts generally.

Brazing are weaker thanwelding joints but stronger thansoldering joints. This can beused to bear the load up tosome extent.

2 Temperature required is 3800degree Centigrade in Welding joints.

Temperature requirement isup to 450 degree Centigradein Soldering joints.

Temperature may go to 600degree Centigrade in Brazingjoints.

3 Work piece to be joined need to beheated till their melting point.

Heating of the work pieces isnot required

Work pieces are heated butbelow their melting point.

4 Mechanical properties of base metalmay change at the joint due toheating and cooling.

No change in mechanicalproperties after joining.

May change in mechanicalproperties of joint but it is almostnegligible.

5 Heat cost is involved and high skilllevel is required.

Cost involved and skillrequirements are very low.

Cost involved and sill requiredare in between others two.

6 Heat treatment is generally requiredto eliminate undesirable effects ofwelding.

No heat treatment is required. No heat treatment is requiredafter brazing.

7 No preheating of workpiece isrequired before welding as it iscarried out at high temperature.

Preheating of workpiecesbefore soldering is good formaking good quality joint.

Preheating is desirable to makestrong joint as brazing is carriedout at relatively lowtemperature.