ULTRASONIC WELDING

SUBMITTED BY-SHUBHANGI OJHA

ME-3RD YEAR

CONTENTSBRIEF HISTORYINTRODUCTIONCLASSIFICATIONMECHANISMPROCESS VARIABLESADVANTAGESLIMITATIONSAPPLICATIONS

BRIEF HISTORY Ultrasonic welding was first developed in the

1940’s. But it was used industrially in 1960’s. In 1960 Sonobond Ultrasonics,originally

known as Aeroprojects, Incorporated, developed the first metal ultrasonic welding machine to be awarded a United States Patent.

In 1963 it was introduced into the plastic welding process and it has since been the most popular welding method.

INTRODUCTION What is welding?

What are ultrasonic waves?

What is ultrasonic welding?

WHAT IS ULTRASONIC WELDING?A solid state welding process.

Wherein high-frequency ultrasonic vibrations are locally applied to workpieces being held together under pressure.

Which results in coalescence between the two pieces to be joined.

CLASSIFICATION OF ULTRASONIC

WELDINGMETAL WELDING

PLASTIC WELDING

Mainly non-ferrous metals and alloys.

Aluminium,copper,nickel,molybednum etc.

Precious metals like platinum,gold,silver etc.

ThermoplasticsAmorphous as

well as crystalline.

ULTRASONIC WELDING

COMPONENTSComponents of ultrasonic welding system include:Power supply-sonic

generatorTransducerBoosterSonotrode or HornAnvilPneumatic system

ULTRASONIC WELDING

MECHANISM(METALS) A static clamping force

is applied perpendicular to the interface between the work pieces.

The contacting sonotrode oscillates parallel to the interface.

Combined effect of static and oscillating force produces deformation which promotes welding.

ULTRASONIC WELDING MECHANISM(PLASTICS)

One of the materials usually has a spiked energy director which contacts the second plastic part

Horn moves to and fro vertically.

ultrasonic energy melts the point contact between the parts, creating a joint.

ULTRASONIC WELDING

MECHANISM(PLASTICS)

ULTRASONIC WELDING

VARIABLESUltrasonic powerClamping forceWelding time Frequency Linear Vibration Amplitude

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 H = Vickers hardness

number T = thickness of the

sheet

ADVANTAGESNo heat is applied and no melting

occurs(METALS)No fumes or odour.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.

No filler metal is used.Energy efficiency, high productivity with low

costs.

LIMITATIONSThe thickness of the component

adjacent to the sonotrode tip must not exceed relatively thin gages because of power limitations of the equipment.

Process is limited to lap joints.Butt welds can not be made because

there is no means of supporting the workpieces and applying clamping force.

APPLICATIONSAssembling of electronic components

such as diodes and semiconductors with substrates.

Electrical connections to current carrying devices including motors, field coils, and capacitors.

Encapsulation and packaging.Plastic parts

APPLICATIONSAppliance: steam iron, pump housing,

vacuum cleaner wand, and dishwasher spray arm.

Automotive: lenses, filters,valves,glove box door, instrument cluster, air diverter and mass airflow sensor.

Electrical: terminal blocks, connectors, switches.

Medical: arterial filter, cardiometry reservoir, blood/gas filter, face mask and IV spike/filter.

CONCLUSION In conclusion ultrasonic welding has many

advantages over other welding techniques for many type e of connections. These include speed, cost, reliability and many others. However, it should also be made clear that it is only ideal for a relatively small proportion of all of the possible joints. Ultrasonic welding should not be seen as a replacement for other techniques, such as GTAW, resistance, laser etc; but rather as an option in situations for which it is well situated.

BIBLIOGRAPHYO.P. Khanna “WELDING

TECHNOLOGY”.Staple ultrasonic corporation

“Principles and applications of high grade bonding technology”.

Richard L Little “WELDING AND WELDING TECHNOLOGY”.

Internet.

THANK YOU

QUERIES?????