61
ME 4210: Manufacturing Processes and Equipment Prof. J.S. Colton © GIT 2011 1 Casting Processes ver. 2

Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

  • Upload
    lyngoc

  • View
    232

  • Download
    10

Embed Size (px)

Citation preview

Page 1: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

1

Casting Processes

ver. 2

Page 2: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

2

Types of Parts Made

• Engine blocks

• Pipes

• Jewelry

• Fire hydrants

Page 3: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

3

Complex, 3-D shapes

• Near net shape

• Low scrap

• Relatively quick process

• Intricate shapes

• Large hollow shapes

• No limit to size

• Reasonable to good surface finish

Page 4: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

4

Processes

• Sand

• Shell

• Plaster

• Ceramic

• Investment

• Lost foam

• Pressure

• Vacuum

• Die

• Centrifugal

• Squeeze

• Semi-solid

• Single crystal

• Directional

solidification

• Slush

• Continuous

Page 5: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

5

Metals processed by casting

• Sand casting – 60%

• Investment casting – 7%

• Die casting – 9%

• Permanent mold casting – 11%

• Centrifugal casting – 7%

• Shell mold casting – 6%

Page 6: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

6

Breakdown of Castings

• Ingots for bulk deformation processing -

85%

• Cast to near net shape - 15%

Page 7: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

7

Ingots

• Iron or steel molds

• Water-cooled molds

• Continuous casting

Page 8: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

8

Shapes

• Expendable Molds

– sand

– shell

– slurry

– investment

• lost wax

• lost foam

• Permanent mold

(cavity)

– die casting

– hot chamber

– cold chamber

Page 9: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

9

Shapes

• Centrifugal

– pipes

– spinning

Page 10: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

10

Capabilities

• Dimensions

– sand casting - as large as you like

– small - 1 mm or so

• Tolerances

– 0.005 in to 0.1 in

• Surface finish

– die casting 8-16 micro-inches (1-3 mm)

– sand casting - 500 micro-inches (10-25 mm)

Page 11: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

11

Casting Steps quick route from raw material to finished

product

• Melt metals

• Pour / force liquid into hollow cavity

(mold)

• Cool / Solidify

• Remove

• Finish

Page 12: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

12

Melting

• Raw material (charge)

– scrap, alloying materials

• Atmosphere

– Air (oxygen), vacuum, inert gas (argon)

• Heating

– External - electric, gas, oil

– Internal - induction, mix fuel with charge • steel making in blast furnace -mix coke with iron

• Furnace material

– refractory ceramics

Heat

Raw materials

Furnace

Atmosphere

Page 13: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

13

Furnaces

Blast furnace Basic Oxygen Furnace

Page 14: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

14

Furnaces

Electric Arc Furnace

Oxygen-Fuel,

Oxygen Lance Furnace

Page 15: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

15

Furnaces

Induction Furnace Electric Furnace

Page 16: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

16

Sand Casting

Page 17: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

17

Sand Casting

Page 18: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

18

Sand Casting

Page 19: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

19

Sand Casting Steps

Page 20: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

20

Page 21: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

21

Sand Cast Parts

Page 22: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

22

Permanent Mold Casting

Page 23: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

23

Low Pressure Casting

Page 24: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

24

Die Casting (high pressure)

Page 25: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

25

Die Casting Machine

Page 26: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

26

Die Casting

Cold chamber

Hot chamber

Page 27: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

27

Direct Squeeze Casting

Page 28: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

28

Die Casting Part Example

Page 29: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

29

Continuous Casting

Page 30: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

30

Page 31: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

31

Page 32: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

32

Page 33: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

33

Investment

Casting

Page 34: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

34

Vacuum Casting

Page 35: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

35

Investment (top) and Conventional

Castings

Page 36: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

36

Lost Foam Casting

Page 37: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

37

Lost Foam Castings

Page 38: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

38

Centrifugal Casting

vertical sand-lined mold

casting

horizontal

Page 39: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

39

Centrifugal Casting

Page 40: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

40

Pipe Casting

Process

Page 41: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

41

Directional Solidification

Page 42: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

42

Casting Characteristics Table 5.6

Typical Weig ht (kg)

Typical

surface

Section

thickness (mm)

Process

materials

cast Minimum Maximum

finish

(micron,

Ra) Porosity*

Shape

complexity

*

Dimensional

accuracy* Minimum Maximum

Sand All 0.05 No limit 5-25 4 1-2 3 3 No limit

Shell All 0.05 100+ 1-3 4 2-3 2 2 --

Expendable

mold

pattern All 0.05 No limit 5-20 4 1 2 2 No limit

Plaster

mold

Nonferrou

s (Al, Mg,

Zn, Cu) 0.05 50+ 1-2 3 1-2 2 1 --

Investment

All

(High melting

pt.) 0.005 100+ 1-3 3 1 1 1 75

Permanent

mold All 0.5 300 2-3 2-3 3-4 1 2 50

Die

Nonferrou

s (Al, Mg,

Zn, Cu) <0.05 50 1-2 1-2 3-4 1 0.5 12

Centrifugal All -- 5000+ 2-10 1-2 3-4 3 2 100

*Relative rating: 1 best, 5 worst.

Note : These ratings are only general; significant variations can occur, depending on the methods used.

Page 43: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

43

Microstructure

Page 44: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

44

Microstructure - Dendrites

• Finer structure at

walls

• Grains / dendrites

grow to center

Page 45: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

45

Grains on Willie B’s head

Page 46: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

46

Microstructure - Dendrites

Page 47: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

47

Fluidity

Page 48: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

48

Casting Defects - Porosity

Page 49: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

49

Casting Defects

Page 50: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

50

Shrinkage

TABLE 5.1

Metal or alloy

Volumetric

solidification

contraction (%) Metal or alloy

Volumetric

solidification

contraction (%)

Aluminum 6.6 70%Cu–30%Zn 4.5

Al–4.5%Cu 6.3 90%Cu–10%Al 4

Al–12%Si 3.8 Gray iron Expansion to 2.5

Carbon steel 2.5–3 Magnesium 4.2

1% carbon steel 4 White iron 4–5.5

Copper 4.9 Zinc 6.5

Source: After R. A. Flinn.

Page 51: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

51

Differential Cooling

• Transition between thicker and thinner

sections can lead to porosity

Page 52: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

52

Pipe Defect

• Due to shrinkage giving rise to

a funnel-like cavity

• Solutions

– insulate top (glass wool)

– heat top (exothermic mixture -

thermit)

Page 53: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

53

Defects - Hot Tears

Page 54: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

54

Chills

Page 55: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

Car Rims

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

55

Stamped Cast

Page 56: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

56

Casting Defects - Porosity

Page 57: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

57

Design Rules Summary

• Uniform wall thickness

• Flat parting lines

• Gradual thickness

transitions

• Draft for removal

– tapers: 0.5 to 2 degrees

• Surface of mold gives

surface of part

Page 58: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

58

Sand Casting Rules

Page 59: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

59

Casting costs

TABLE 5.10

Cost*

Process Die Equipment LaborProductionrate (Pc/hr)

Sand L L L–M <20Shell-mold L–M M-H L–M <50Plaster L–M M M–H <10Investment M–H L-M H <1000Permanent mold M M L–M <60Die H H L–M <200Centrifugal M H L–M <50

* L, low; M, medium; H, high.

Page 60: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

60

Process economics

Page 61: Casting - erranjitsingh.weebly.com · •Vacuum •Die •Centrifugal •Squeeze •Semi-solid •Single crystal • Directional solidification •Slush ... –die casting –hot

ME 4210: Manufacturing Processes and Equipment

Prof. J.S. Colton © GIT 2011

61