this presentation is about ultrasonic welding ,it shows what is ultra sonic welding and how does it work with some applications .
I am a student at port said university ,faculty of engineering ,production and mechanical design department .
2. CONTENTS
INTRODUCTION
WHY TO USE US WELDING
ULTRASONIC WELDING PROCESS
ULTRASONIC WELDING MECHANISM
PRINCIPLE OF ULTRASONIC MACHINING
JOINT FORMS WITH ULTRASONIC MACHINING
SPOT WELDING IN AIRCRAFT WINGS
ADVANTAGES
DIS ADVANTAGES
APPLICATION
3. INTRODUCTION
Ultrasonic welding is an industrial technique whereby
high-frequency ultrasonic acoustic vibrations are locally
applied to work pieces being held together under pressure
to create a solid-state weld.
6. BOOSTER
Modifies the amplitude of
vibrations
SONOTRODE
Applies the mechanical vibrations
to the parts to be welded
Anvil
MAIN PARTS
7. Ultrasonic Welding
Mechanism
A static clamping force is
applied perpendicular to the
interface between the work
pieces.
The contacting sonotrode
oscillates on the interface.
Combined effect of static and
oscillating force produces
deformation which promotes
welding.
Anvil
Sonotrode
tip
Clamping force
wedge Transducer
Force
workpiece
10-75 KHz
8. Principle of Ultrasonic
Welding
Anvil
Mass
Sonotrode
tip
Clamping
force
wedge Transducer
Force
WeldmentVibration
*In US welding, frictional heat
produced by the ultrasonic waves
and force is used for joining
process.
*US waves(15to60 kHz) are
transferred to the material under
pressure with a sonometer.
Welding times are lower than 3 s.
*It can proceed with or without the
application of external heat.
9. Ultrasonic Welding Power
Generation
Frequency is transformed to
vibration energy through the
transducer.
Energy requirement established
through the following empirical
relationship.
E = K (HT)3/2
E = electrical energy, W*s (J)
H = Vickers hardness number
T = thickness of the sheet
Electrical
energy
Frequency
Converter
Vibratory
transducer
10. Interfacial Interaction
Localized Plastic Deformation
Localized temperature rises resulting from interfacial slip and
plastic deformation.
Temperature is also influenced by power, clamping force, and
thermal properties of the material.
Metallurgical phenomena such as recrystallizing, phase
transformation, etc..... can occur.
12. Why to use US welding?
First - Ultrasonic assembly uses ultrasonic vibratory energy
which is transmitted through the parts to melt and bond
thermoplastic materials And joining thin sheet gauge metals
and other lightweight materials
Second - This technique is fast, efficient, non-contaminating .
Third - In ultrasonic welding, there are no connective bolts,
nails, soldering materials, or adhesives necessary to bind the
materials together.
13. Types of US welding
Spot Welding
Line Welding
- Linear Sonotrode
Continuous Seam Welding
- Roller Sonotrode
15. Sonotrode Tip and Anvil Material
High Speed Tool Steels used to weld
Soft Materials
Aluminum
Copper
Iron
Low Carbon Steel
Hardenable Nickel-Base Alloys used to weld
Hard, High Strength Metals and Alloys
18. Advantages of Ultrasonic
Welding
No heat is applied and no melting occurs
Permits welding of thin to thick sections
Welding can be made through some surface coatings
Dissimilar metals having vastly different melting points can
be joined
Pressures used are lower, welding times are shorter, and the
thickness of deformed regions are thinner than for cold
welding
19. Limitations of Ultrasonic
Welding
Competitively not economical
Process is limited to lap joints.
Butt welds can not be made because there is no means of
supporting the work pieces and applying clamping force.
Due to fatigue loading the life of equipment is short.
This process is limited to small welds of thin, malleable metals
Eg: Aluminium, Copper, Nickel
20. Applications of Ultrasonic
Welding
Computer and electrical industries delicate
circuits, Junctions of wire harnesses , flash drives and
computer disks, Semiconductor devices
Aerospace and automotive industries instrument panels,
door panels, lamps, air ducts, steering wheels, and engine
components
Medical industry
21. Applications
Manufacturing of toys
Joining of electrical and electronic components
Welding aluminium wire and sheet
Mobiles, sports shoes , laminations, cars.
Packing , medical industries, computers.
6/8/2014SUBHASIS.....MIT BBSR
21
#9: Typical components of an ultrasonic welding system are illustrated in the above figure. Linear ultrasonic vibrations are generated in the transducer and transferred to a sonotrode. The anvil holds the components in a fixed position and supports the clamping force.
#10: The energy required to make an ultrasonic weld can be related to the hardness of the workpieces and the thickness of the part in contact with the sonotrode tip. Analysis of data covering a wide range of materials and thickness has led to the above empirical relationship. The constant k is a complex function that appears to involve primarily the electro-mechanical conversion efficiency of the transducer, the impedance match into the weld, and other characteristics of the welding system. Different types of transducer systems should have substantially different k values.