Electroplating PPT
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Transcript of Electroplating PPT
Electroplating
Supervisor: Pham Thanh DuongGroup : Nguyen Thi Ngoc Diep
Vo Thi Thuy HaBui Thi Thuy Ngan
Main partDefinition
Brief history
Objectives
Preparing of surface
Electroplating process
Advantages and disadvantages
Definition of Electroplating
“Electroplating is a plating process in which metal ions in a solution are moved by an
electric field to coat an electrode.”
History of Electroplating
was first discovered by Luigi Brugnatelli in
1805
the use of more eco-friendly formulas
using direct current power supplies.
Objective of Electroplating
Prevent corrosion
Obtain a hard surface or attractive finish
Purify metals
Separate metals for quantitative analysis
E.g.: Cadmium, chromium, copper, gold, nickel, silver, and tin.
Preparing the Surface
1st step: cleaning
2nd step: treatment
3rd step: rinsing
Preparing the Surface
Chemical cleaning
Physical cleaning
How electroplating is done
Preparation
• Cathode made of copper or steel ;
Anode made of Nickel
• Blue wire attached to the Cathode and
negative pole of battery
• Red wire attached to the Anode and
positive pole of battery
• The cell filled with an Electrolyte
containing NiCl2
Process• The NiCl2 ionizes into water
NiCl2 --> Ni2+ + 2Cl-
• The object is negatively charged -> attracts Ni2+ and gives up electrons
• The nickel atom will be deposited on the surface of the part being coated
-> Electrodeposition
Faraday’s laws Electroplating is based on Faraday’s laws of electrolysis:
1st : the mass of a substance liberated in electrolysis is proportional to the quantity of electricity passed through the cell
2nd : the mass of the material liberated is proportional to its electrochemical equivalent.
The amount of nickel that would have been electroplated is proportional to the number of electrons the battery provides
Advantages &
Disadvantages
Variety of Uses
A wide range and size of items conductor parts - printing
rolls insides of wires and tubes
A wide range, shape and sizes of decorative applications jewelry, watches, optical
frames and writing instruments
Advantages
Advantages
Coatings: nickel, copper and chromium
not react with porcelain
enamels and electrical
connections
not change the fundamental
nature of their base metal.
Advantages
Advantages
Safety Rigid specifications promulgated by
governmental bodies, local associations and international standardization (ISO)how to perform coatingssafety standards to maintainequipment to use based on experience
and expert’s opinion
Advantages
Disadvantages
Coatings working on a molecular level
thin coat If repeat it over and over again
time consuming and expensive Uniformity
Sometimes be lumpy and uneven often grind and machine the parts
Disadvantages
DisadvantagesBrittleness
Electroplating a good coating of a superior metal onto a lesser metal => coating often be brittle and easy to crack
Micro-crack may lead to the overall destruction of the electroplated layer electroplate multiple layers
Disadvantages
References• http://www.ehow.com/search.html?
q=advantages+of+electroplating&skin=home• http://www.ehow.com/
list_6850757_electrolytic-plating-advantages.html
• http://en.wikipedia.org/wiki/Electroplating
Thank you for listening!