Page 100 - Module DMV20173

5. 0 JOINING PROCESSES

Example 5.2

Describe the process characteristics of resistance welding.

Solution:

Process characteristics:
1. Requires no filler metal or fluxes.

2. Can achieve high speed production.

3. Is easily automated.

4. Does not require skilled operators.

5. Is used primarily on sheet metal.

6. Uses non-consumable, low resistance, copper allow electrodes.

5.4 BRAZING

Figure 5.8 Brazing process.

1. Brazing is the coalescence of a joint with the help of filler metal (Figure 5.8).

2. Braze welding joins two pieces of metal (may be dissimilar) where the base metals
are not heated to the melting point. A brazing rod of lower melting temperature is

used to bond the two base metals.
3. Filler metal liquidus temperature is above 450°C and is below the solidus

temperature of the base metal.

4. The filler metal is drawn into the joint by means of capillary action (entering of fluid
into tightly fitted surface).

5. This process where base metal is not melted, but joint is obtained by means of a filler
metal.

6. Sequence of brazing process shown in Figure 5.9

BPLK 132 DMV 20173