This document summarizes several solid-state welding processes including cold welding, forge welding, ultrasonic welding, diffusion welding, and explosive welding. Solid-state welding involves joining metals without melting them through the application of pressure, vibration, or heat below melting temperatures. Key advantages are producing high quality welds without defects between similar and dissimilar metals. The processes require clean surfaces and pressure or precise control of vibration/temperature parameters to produce strong bonds at the atomic level.

1. Solid-State Welding
Process
Presented By:
Abdullah Mansoor-42
Ahmed Ali Zafar-66
Waleed Raza-52
Abu-Bakr-64

2. Contents
 Welding
 Solid State Welding
 Cold Welding
 Forge Welding
 Ultrasonic Welding
 Diffusion Welding
 Explosive Welding

3. Welding
 Welding is a material joining process
in which two or more metals are
joined at their contacting surface by
applying the suitable pressure or heat.
 Many welding process accomplished
by heat alone with no pressure
applied.
 Some other process accomplished by
pressure alone no external heat
supplied; other accomplished both
heat and pressure.

5. Solid State Welding:
 A welding process in which
coalescence takes place at
temperatures below the melting
point of the metals being joined and
without use of a brazing filler metal.
 Sometimes this is accomplished
through the use of pressure.
 Weld (bonding) is free from
microstructure defects .
 Dissimilar metals may be joined .

6. Forge Welding (FOW)
Cold Welding (CW)
Explosive Welding (EXW)
Diffusion Welding (DFW)
Ultrasonic Welding (USW)

7. Cold Welding
 Pressure is applied to the
workpieces through dies or rolls
at room temperature.
 Preferably both work pieces
should be ductile
 The work pieces should cleaned
thoroughly
 Best bond strength occurs with
two similar metals.
 Aluminum alloys, Copper
alloys, low carbon steels, Nickel
alloys, and other ductile metals
may be welded by Cold
Welding.

8. Fig: The roll bonding or cladding process

9. Advantages of cold welding:
 No heat is required
 Optimum weld seam quality
 High accuracy of workpiece material
 Dissimilar metals can be joined by cold welding.
Disadvantage:
o High pressure is required.
o Metal to be welded must be ductile.
o Contact surface must be clean.

10. Forge welding:
 Forge welding is process in
which components to be
joined are heated to hot
temperature and then
forged together by
hammer.
 The process is one of the
simplest method of joining
used in ancient times.

12. Advantages of Forge Welding:
 Good weld quality may be obtained.
 Parts of intecrate shap can be welded.
 No filler material use during welding.
Disadvantages:
 Slow welding process.
 High operational skills are required.
 Only low carbon steel may be welded.

13. Ultrasonic Welding
 Surfaces of the two
components are
subjected to a static
forces and oscillating
shearing force
 Produces a strong,
solid-state bond
 Versatile and reliable
for joining metals

15. Advantages of Ultrasonic welding
 Dissimilar metals may be joined.
 High quality weld is obtained.
 Very low deformation of work piece surfaces.
 Moderate level skills are enough.
 This process may be integrated in automated production line.
Disadvantage:
 Only small and thin parts may be welded.
 Work piece may be bond to anvil.
 Work pieces and equipment may be fatigue due to
reciprocating loads of ultrasonic vibration.

16. Diffusion Welding:
 Pressure is applied to two different workpieces with carefully cleaned
surfaces and at elevated temperature of material below the melting points of
metals.
 Bonding of material is a result of mutual diffusion of thier atoms.
 Diffusion welding can be joined disimliar metals as compare to others
welding processes.
▪ Steel to tungstun.
▪ Steel to noibium.
▪ Steelness Steel to Titanium.
▪ Gold to copper alloys.

18. Advantages of diffusion welding:
 Disimliar metals canbe joined.
 Welding is obtained at high quality.
 No limitations in the thickness of workpiece.
Disadvantages:
 Time consuming process with low productivity.
 Relatively high initial invesments in equipement.
 The meeting surfaces must be fitted to each other.
 Very thorough surface prepration to piror welding process.

19. Explosive Welding:
 Processin which welded parts are metalluragically bonded as a result of
obique impact pressure exerted on them by controlled detonation of an
explosive charge.
 The maximum detonation velocity is about 120% of the material sonic
velocity.
 Most of commercial metals and alloys may be bonded by explosive
welding.
 Disimlar metals may be joined which are following:
 Copper to steel
 Nickal to steel
 Aluminium to steel
 Titanium to steel
 Tungstun to steel

21. Advantages of Explosive Welding:
 Good bond strength achieved.
 Ehanced mechanical properties by joining the metals.
 Extremely big surface can be join.
 Broad range of thicknesses can be explosively clad joint.
 Metal can be created on heat-treated metals with no affecting their
microstructures.
Disadvantages:
 Brittle material cannot procced.
 Only simple parts may be bonded,plates,clyinders;
 Thickness of flyer plate is limited-(63mm).
 Safety and security aspects of storage and explosives.