Electron Beam Machine

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Electrons Beam Machine

Dr. Essam Qasem

Al- Balqaa Applied UniversityAl- Huson University College

Mechanical Engineering Department

Team #



Team Members:

Mohammad !aqou" $$%$$&'$

Ammar Mal(a)i $$$%$$'*'

Murad +a)ashdeh $*$%$$'%

,ade Al .hatee" $/$%$$'$$



Contents:

• 0ntroduction

• 1rocess

•

Equipment Used• 1arameters

• Capa"ility

• Advantages and Disadvantages

• Applications



Introduction

Electron "eam machining 2EBM3 is a thermal process used4or the metal removal during the machining process5 0n theelectrical "eam machining6 electrical energy is used togenerate the electrons )ith high energy.

)EBM(is a process where high-velocity electrons concentrated into anarrow beam are directed toward the work piece, creating heat andvaporizing the material. EBM can be used or very accurate cutting or

boring o a wide variety o metals. !urace "nish is better and kerwidth is narrower than those or other thermal cutting processes.



Process of Electron BeamMachining:

0n the electron "eam gun the electric "eam isgenerated5 Electron "eam consists o4 a small spotsi7e6 4rom )hich it provides the high velocityelectrons5 The electron "eam machining process iscarried out in the vacuum5 This is due to theelectrons present in the process react )ith the airmolecules so they lose the energy and a"ility o4cutting5 The )or( piece material must "e placedunder the electron "eam6 and )here the equipment

is placed under the vacuum5 ,ith the spot si7e o4 $'to $'' 6 the high energy a"sor"ed electron "eam isready to sho) impact on the )or( piece material.



The high velocity electron consists o4 (inetic energy6the energy is converted into the heat energy6 )herethe electrons stri(es the )or( material5 Because o4the high energy present in the electrons it starts tomelting and vapori7ation o4 the )or( piece material5

The process is done 4rom top to the "ottom o4 the

)or( piece material5 0n the electrical "eammachining the gun is used in the pulsed mode5 Byusing the single pulse holes6 and is drilled on the thinsheets5 Multiple passes are required 4or the thic(er

plates.



Equipment used in the ElectronBeam Machining:



The electron "eam machine consists o4 an electron"eam gun used to produce 4ree electrons at the

cathode5 The high velocity particles are movingthrough the small spot si7e5 The cathode 2tool3 ismade o4 tantalum or tungsten material5 The cathode9laments are heated to a temperature o4 /&''to

'''and the heating leads to thermo : ionic emissiono4 electrons5 The magnitude varies 4rom the /& mA to$'' mA5 The solidities lies "et)een & Ac to $& Ac 5Theemission current is in;uenced "y the voltage that isnearly $&'(<6 and the current is applied "et)een the

anode and cathode to release the electrons in thedirection o4 )or( piece.



• Bias grid: 0t is also (no)n as grid cup5 The gridcup is a negative that is su"ected )ith respect to

the 9lament5 =o6 the electrons generated )ith thehelp o4 the cathode )ill directly ;o) to)ards theanode5 During the ;o) o4 the electrodes nodiversions are seen5 The anode attracts the

electrons and gets accelerated> the electrons )illgain a high velocity5

• The cathode controls the ;o) o4 the electrons6 andthe grid cup used to operate the gun in pulsedmode only5



• A4ter the anode the electron "eam passing throughthe magnetic lens and the apertures are connected inseries5 The magnetic lens is used to shape theelectron "eam and reduce the diversion 4actor5

• The apertures allo) the convergent electrons to

permit and caught the lo) energy divergentelectrons 4rom the 4ringes5

• ?inally the electron "eam passes through the

electromagnetic lens and de;ection coil5 Then thede;ection coil sends the electron "eam through thehole6 to improve the shape to machine a hole5



• The vacuum is created "et)een the )or( piece andthe electron "eam gun6 and there is a series o4

rotating disc )ith slots5

• The disc allo)s the electron "eam to pass over thematerial 4or machining6 and it prevents 4rom the4umes and vapors generated during the machining5

• ,or( piece is placed on the C@C "ench5 Then holes

o4 any shape are made on the )or( piece material5 0nthe gun "eam ;ection and C@C control are used toshape5



• <acuum is maintained in gun6 and the vacuumranges 4rom =uita"le vacuum is maintained "ecause

the electron as it does not lose their energy6 and)here the li4e o4 the cathode is o"tained5 By usingthe diusion pump and rotary pump the vacuum ismaintained5

• Diusion pump should act as an oil heater5 04 the oilis heated then the oil vapor rushes up)ards5 Theno77le changes the direction o4 the oil vapor andstarts moving in the do)n)ard direction at high

velocity5 The oil vapors are reduces in the diusionpump> this is "ecause o4 the presence o4 the cooling)ater cover5



:Parameters in the !EBM"

• already (no) that the electron gun is )or(s )ithin thepulse mode5 The "ias grid is located a4ter the cathode5

Then pulse is given to the grid cup6 )here the pulseduration ranges 4rom &'to $& ms5

• Beam current is related to the electrons that areemitted 4rom the cathode or availa"le in the "eam5Beam current is ranges 4rom the /''micro amps to $amp5 04 the "eam current increases6 simultaneously there

is also an increase in the energy per pulse5 High pulseenergy is used to machine thic(er plates and ma(e theholes larger5



• The po)er and energy density is ruled "y the energy perpulse and the no77le spot si7e5 ,ith the help o4 theelectromagnetic lens the spot si7e is controlled5 ?or lo)erspot si7e they require a high energy density5 The metalremoval must "e high> this is )hen compared to the holes

si7e )here the hole must "e similar5

• The plane o4 4ocusing must "e a"ove or "elo) the sur4aceo4 the )or( piece material5



Capabilit# of !EBM" process:

•

Electrical "eam machining ma(es a hole ranges 4rom$'' to / mm5

• The depth o4 cut must "e $& mm )ith a length todiameter ratio o4 nearly $'5•

Holes can "e elongated along )ith the "arrel shape ordepth5

• +everse tapper can also "e per4ormed "elo) thesur4ace o4 the )or( piece material5

• 0n the electron "eam machining Cut 4ormation is noto"served



• 0n EBM the heat aected 7one is narro)> this is "ecause o4 theshort pulse occurrence5 The heat aected 7one is nearly /' to '5

• Compares to the steels aluminum and titanium is 4reelymachined5

• Based upon the type o4 the material6 po)er density6 depth o4 cutholes diameter6 )hich are the reasons 4or the num"er o4 holes

drilled per second on the material5

• The EBM does not apply any cutting 4orces on the material5

• During the process very simple investment is required 4or )or(

• EBM process allo)s machining o4 "rittle and 4ragile materials5

• Holes are drilled at an angle o4 /' to '5



:$d%antages of !EPM"

• There is no contact "et)een the tool material and

)or( piece material

• <ery small holes are also machined on dierenttype o4 )or( piece materials )ith high accuracy

• Drilling is also done on the )or( piece material)ith a diameter o4 nearly '5''/ inches

• Drilling parameters are changed automaticallyduring the machining



• Distortions are not o"served to the )or( piecematerial5

• This process is pro9cient in attaining high accuracy

along )ith repeata"ility5

• Compare )ith the other process6 4ormation o4 holes

is easy )ith the other process5



Disad%antages:

• The cost o4 the equipment is very high5

•Metal removal rate during the process is lo)5

•=mall cut operations are per4ormed on the )or(piece material )ith the help o4 EBM machine5

•<acuum requirements "oundaries the dimensions o4the )or( piece material5

•@eed 4or secondary "ac(ing materials5



$pplications of EBM:

,ith the help o4 the dierent pressure6 holes aredrilled in the air cra4t engine6 nuclear reactor etc.



&ideos



The End

Electron Beam Machine

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