Cold welding is a solid-state welding process that uses pressure at room temperature to join metals through substantial deformation without melting. Both butt and lap joints can be formed. At least one metal must be ductile and heating is not applied. Surface preparation is important. The parts are cleaned, sheared, clamped in a die, and a forging force is applied to complete the weld. Advantages include no thermal effects on materials and a simple, fast, inexpensive process. Inspections can be difficult and some processes reduce part thickness. Common applications include wire drawing and sealing of heat-sensitive devices.

1. COLD WELDING
PROCESS
Group - 22

2. Solid
State
Welding
Electrical
Chemical
Mechanical
Pressure
Pressure&
Deformation
ColdWeld

3. • Cold welding is a solid-
state process in which
pressure is used at room
temperature to produce
coalescence of metals
with substantial
deformation at the weld.
Both butt and lap joints
can be cold welded.
Definition of Cold Welding
Die
Flash

4. • At least one of the metals must be
ductile without excessive work-
hardening.
• Total absence of applied heating.
• Dissimilar metals can be joined.
• Surface preparation is important.
Characteristics of Cold Welding

5. Cold Welding Equipment

6. • The parts to be welded are
first cleaned.
• A short section of the part
is sheared.
• The parts are clamped in a
die with some initial
extension.
• A forging force is applied
to complete welding.
Dies
Workpiece Workpiece
Before welding
After welding
Cold Welding Process

8. A: Lap both sides indented E: Draw Weld
B: Lap One side indented F: Wire Lap (before and after)
C: Edge both side indented G: Mash Cap Joint
D: Butt in Tube H: Butt (before and after)
Types of Cold Welding
Processes

9. Advantages and Limitations
• No thermal effects on the material
• Process is simple and fast
• Inexpensive to operate once the dies have been
produced
• Difficult to inspect, since a Solid State welding
• Some processes reduce the thickness of the
parts (Lap joints)

10. • Cold welded butt joints are used in the
manufacturing of aluminum, copper, gold,
silver, and platinum wires with continuous
drawing.
• Most commonly, used in sealing heat sensitive
semiconductor devices.
• Sealing of heat sensitive containers such as
containing explosives.
• Used in underground wire servicing due to
hostile environments (explosive gasses).
Applications of Cold Welding

11. Thank You!