https://www.youtube.com/watch?v=rFKtP_6w4B0&t=1s

1. PHYSICAL METALLURGY
OF METAL JONINING
PRESENTED BY: DARSHIT DESAI
19MMM003

2. Method of joining metals
1. Rivets/Nuts & bolts
2. Soldering
3. Brazing
4. Welding
5. Adhesives
 Soldering & Brazing: Part to be joined do not
melt
 Welding: Metal also melts & solidifies

3. For Good joints:
 wettability, smooth & clean surfaces
 Interfaces Temp. ≥ melting Temp. of filler
B: non wettability
A: wettability

4. Bonding Mechanism
 The continuous metallic bridge between the
two parts provides the bond between the two
metals(part).
Strength Strength Strength
of > of > of
Welding brazing soldering

5. Heat flow during welding
d
t

6.  Point source : multi-pass for
thick plate
 Line source: single-pass for
thin plate
Facture take place

7. HAZ in Steel
1. Weld zone
2. Partially melt zone
3. Excessive grain growth
4. Austenite zone
5. Partial austenite zone
6. Tempered zone
7. Base metal
Austenite+ferrite

8. HAZ in age hardenable alloy
1. Weld metal
2. Partial melting
3. Precipitation
4. Precipitation coarsening
5. Original metal
α

9. Thank you