Allah has blessed us with chance to serve the Nation in the Field of Metallurgy & Materials Engineering

Vacuum Metallurgy

Course Teacher:Engr. Muhammad Ali SiddiquiLecturer/ Area Coordinator ISO 9000MYD, NED UET

Qualification: BE, Metallurgy & Materials Engineering , Mehran UET Jamshoro, 2007ME, Materials Engineering, NED UET Karachi, 2011

Open Discussion/Students Problems:1. Regarding; Study/Teaching 2. Projects/Thesis …. (any information do you want)3. Any Suggestion for Continual Improvement 4. Any other item ….

Vacuum Metallurgy

Sessional Marks DistributionTotal No of Lectures: 48,

03 per week

Thursday = 1st Class

Friday = 1st & 2nd Class

Credit Hours = 3 + 1

Activity in Fall Term Marks Distribution

Attendance (Optional)

05 No>75 % = 5No

75 to 70 % = 4No69 to 65 %= 3No64 to 60 %= 2No59 to 50 %= 1No

<50 5 = 0 No

Total Test = 2 (Each test of 10 No’s) 20

Assignment or Presentation 05

Total 30

Total Marks = 100 No’s.Sessional Marks = 30 No's.

Final Exams Marks = 70 No's.

Introduction to the subjectDifferent units of measuring pressure, vacuum regimesMean free path, Collision frequencyVaccum pumps, Water pumpsPositive displacement pumpRotary and root pumpVapour ejector and vapour entrapment pumpDiffusion pumpTurbo-molecular pumpTestIon pump Sieve pump, Adsorption pumpVacuum Measuring devicesManometer, McLoad Gauge, Peening gauge, Pirani gaugeConductance and through put

Effective pumping speedGas flow through pipes and orificeSources of Leak, Leak detection and remediesTestVacuum Applications in Materials processingVacuum induction furnace, Vacuum arc furnaceMetal refining in vacuum, Degassing in liquid stateVacuum heat treatment, Vacuum sinteringDesign of vacuum furnaceVacuum coating, Purpose of vacuum coatingVacuum coating processProcess of PVD and CVD coatings, vacuum coating characterizationTest

Course Outline:

Introduction to Vacuum.• The word Vacuum is derived from the latin word

Vacuus, which means empty, so in olden times vacuum was thought to be an empty space.• But as the technology improved, the world realized

the importance of vacuum and nowadays the Vacuum is defined as:

• According to American Vacuum Society : “At Standard Temperature and Pressure any space having molecular density less than about 2.5X1019 molecules /cm3 is called a space under vacuum.”• Or Vacuum refers to a given space filled with gas at pressure

below atmospheric pressure (760 torr).

Less are the number of molecules, the better is the vacuum, because there is linear relation between the molecular density and vacuum ranges.

Types of Vacuum• Natural Vacuum• Artificial vacuum

Vacuum generation

Vacuum Monitoring

Vacuum Measurement

Rotary pump

Root

Diffusion pump

Steam ejector

Turbo Molecular

Scroll pump

Thermocouple

Pirani

Peening

Capacitance diaphragm

Bourdon

Hot Cathode

Cryogenic pumps Cold cathode

Spinning Rotor

VACUUM SYSTEM

Leaks Outgassing Back Streaming Back Migration

Vacuum Problems

For Artificial Vacuum

Natural VacuumIn spite of artificial vacuum, there exists also natural vac. of fine quality in upper space. Atm. Pressure decreases with altitude by a factor of 10 for 15Km rise in altitude up to certain height and becomes EXUHV at max. h.

What is Vacuum Metallurgy?

•According to R.F Bunshah in “International Vacuum Metallurgy Conference” 1967 defined Vacuum Metallurgy as:

“the making, shaping and treating's of metal & alloys under pressure ranging from sub-atmospheric to ultra high vacuum in order to improve their properties and service life.”

•Almost all the metals in the periodic table nowadays are produced by vacuum methods or to those that undergo vacuum processes at some stages in their manufacturing.

• The aim of vacuum treatment is essentially the removal or reduction of harmful impurities during production or in the various processes phases, whether for increase the yield, improving of quality, or creation of quite new materials.