DIE CASTING GRAVITY SEMI PERMANENT MOULD OR PERMANENT MOULD COLD CHAMBER HOT CHAMBER (HEATING CHAMBER) OUTSIDE THE MACHINE INTEGRAL WITH THE MACHINE

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  • DIE CASTING

    GRAVITY SEMI PERMANENT MOULDOR PERMANENT MOULD COLD CHAMBER HOT CHAMBER (HEATING CHAMBER) OUTSIDE THE MACHINE INTEGRAL WITH THE MACHINE

  • PERMANENT MOULD OR GRAVITY DIE CASTING*METALLIC MOULDS USED *TWO HALVES OF DIES- ONE FIXED, ONE MOVABLEVERY CLOSE TOLERANCE CASTINGS, MORE STRENGTH, LESS POROUS-BETTER SURFACE FINISH COMPARED TO SAND CASTING-SURFACE FREE FROM SAND & DENSITY HEAVYONLY FOR SMALL AND MEDIUM SIZE CASTINGSFOR NON FERROUS, MAINLYLARGE QUANTITY, BUT IDENTICAL PIECES ONLY

  • SEMIPERMANENT DIECASTINGDIE PRESSURE AT 20 TO 20,000 ATMPRESSURE FILL SOLIDIFICATIONFOR NONFERROUS METALSFOR INTRICATE SHAPESCLOSE TOLERANCES POSSIBLEFOR MASS PRODUCTION, >10,000

    1. A GOOD DIE SET MECHANISM 2. MEANS FOR FORCING METAL 3. DEVICE TO KEEP DIE HALFS PRESSED 4. ARRANGEMENT FOR AUTOMATIC REMOVAL OF CORES- IF ANY 5. EJECTOR PINS

  • TWO TYPES OF PRESSURE DIE CASTING COLD CHAMBER- HEATING CHAMBER OUTSIDE THE MACHINE - FOR Al, Mg, Cu, AND HIGH MELTING ALLOYS HOT CHAMBER- HEATING INTEGRAL WITH THE HANDLING GOOSE NECK MECHANISMS WIDELY USED FOR LOW MELTING ALLOYS- Zn, Pb, Etc.ALSO VACUUM DIE CASTING MACHINES- SPACE BETWEEN THE DIES AND PASSAGE VACUUMISED BEFOR POURING- SUBMERGED PLUNGE TYPE, DIRECT AIR DIE CASTING MACHINES

  • 231123

  • D.A.D.C. MACHINE showing two positions of pot

  • ANOTHER TYPE OF D.A.D.C. MACHINE

  • A TYPICAL DIE ECCENTRIC CLAMPINGMOULD / DIE HALFVENT HOLEPOURING BASIN

    MOULD CAVITY

  • CENTRIFUGAL CASTINGTRUE- C.I. PIPES, LINERS, BUSHES, CYLINDER BARRELS ETC.SEMI- CENTRE CORE FOR INNER SURFACE- SHAPE BY MOULD AND CORE, MAINLY NOT BY CENRTRIFUGAL ACTION- Eg:FLYWHEELSPRESSURE OR CENTRIFUGAL CASTING- ALSO TERMED AS CENTRIFUGINGFOR NON SYMMETRICAL SHAPES MOULD WITH ANY SHAPE PLACED AT CERTAIN DISTANCE FROM AXIS

  • CENTRIFUGING PROPERTIES OF CASTING DEPEND ON DISTANCE FROM AXIS

    SQUEEZE CASTINGDIE, PUNCH, EJECTOR PINPARTS OF NEAR-NET SHAPE MADE, COMPLEX AND FINE SURFACE DETAILS OBTAINEDFOR FERROUS & NON FERROUS

  • CENTRIFUGING PROPERTIES OF CASTING DEPEND ON DISTANCE FROM AXIS

    SQUEEZE CASTINGDIE, PUNCH, EJECTOR PINPARTS OF NEAR-NET SHAPE MADE, COMPLEX AND FINE SURFACE DETAILS OBTAINEDFOR FERROUS & NON FERROUS

  • SQUEEZE CASTINGDEVELOPED IN 1960S (also called liquid forging)SOLIDIFICATION OF MOLTEN METAL UNDER HIGH PRESSURE (pressure application when liquid partially solidifies 70 to 140 MPa)A COMBINATION OF CASTING & FORGINGDIE, PUNCH, EJECTOR PIN PUNCH KEEPS ENTRAPPED GASES IN SOLUTION, RAPID COOLING DUE TO HIGH PRESSURE DIE- METAL INTERFACEPARTS OF NEAR-NET SHAPE MADE, COMPLEX AND FINE SURFACE DETAILS OBTAINED. No riser needed FOR FERROUS & NON FERROUSAUTOMOTIVE WHEELS, SHORT BARRELED CANNONS ETC.

  • SINGLE CRYSTAL GROWING (S.C.G.)FOR SEMICONDUCTOR INDUSTRYCRYSTAL PULLING METHOD- CZOCHRALSKI PROCESSSEED CRYSTAL DIPPED INTO THE MOLTEN METAL, PULLED SLOWLY, (AT 10 m/ s), WITH ROTATION

    LIQUID METAL SOLIDIFIES ON THE SEED AND CRYSTAL STRUCTURE CONTINUED THROUGHOUT

  • CASTING TECHNIQUES FOR SINGLE CRYSTAL GROWING (S.C.G.)CONVENTIONAL USE OF CERAMIC MOULDGRAINS WITH THE ABSENCE OF THERMAL GRADIENTDIRECTIONAL SOLIDIFICATION PROCESS CERAMIC MOULD PREHEATED. MOULD SUPPORTED BY WATER COOLED CHILL PLATES.AFTER POURING, ASSEMBLY LOWERED CRYSTALS GROW AT CHILL PLATE SURFACE UPWARD. COLUMNAR GRAINS FORM

  • CASTING TECHNIQUES FOR SINGLE CRYSTAL GROWING (S.C.G.)POLYCRYSTALLINE- ANISOTROPYSINGLE CRYSTAL- PROPERTIES SAME IN ALL DIRECTIONSCASTING OF GAS TURBINE BLADES BY S.C.G.

  • CONVENTIONAL

    USE OF CERAMIC MOULDGRAINS- AS WITH THE ABSENCE OF THERMAL GRADIENTPRESENCE OF GRAIN BOUNDARIES- MAKES STRUCTURE SUSCEPTIBLE TO CREEP AND CRACKING ALONG BOUNDARIES

  • DIRECTIONAL SOLIDIFICATION PROCESS, (1960s) CERAMIC MOULD PREHEATED. MOULD SUPPORTED BY WATER COOLED CHILL PLATES.AFTER POURING, ASSEMBLY LOWERED CRYSTALS GROW AT CHILL PLATE SURFACE UPWARD. COLUMNAR GRAINS FORMBLADE DIRECTIONALLY SOLIDIFIED WITH LONGITUDINAL- NOT TRANSVERSE- GRAIN BOUNDARIES. THUS STRONGER

  • SINGLE CRYSTAL BLADES, (1967),MOULD HAS CONSTRICTION IN THE SHAPE OF CORK SCREWTHIS CROSS SECTION ALLOWS ONLY ONE CRYSTAL TO FIT THROUGHWITH THE LOWERING, SINGLE CRYSTAL GROWS UPWARD THROUGH CONSTRICTIONSTRICT CONTROL OF MOVEMENT NEEDEDTHERE IS LACK OF GRAIN BOUNDARIES, MAKES RESISTANT TO CREEP AND THERMAL SHOCK.--EXPENSIVE

  • FLOATING ZONE METHODPOLYCRYSTALLINE ROD (SILICON)- ALLOWED TO REST ON A SINGLE CRYSTALINDUCTION COIL HEATS THE PIECESCOIL MOVED UPWARD SLOWLY (20 m/ s) SINGLE CRYSTAL GROWS UPWARD WITH ORIENTATION MAINTAINEDTHIN WAFERS CUT FROM ROD, CLEANED, POLISHEDUSE IN MICROELECTRONIC DEVICES