Process

Roughness Range, Ra – Micrometers μm

Maximum

Minimum

Flame Cutting

25

12.5

Snagging

25

6.3

Sawing

25

1.6

Planing, Shaping

12.5

1.6

Drilling

6.3

1.6

Chemical Milling

6.3

1.6

Elect. Discharge Machining

4.75

1.6

Milling

6.3

0.8

Broaching

3.2

0.8

Reaming

3.2

0.8

Electron Beam

6.3

0.8

Laser

6.3

0.8

Electrode-Chemical

3.2

0.2

Boring, Turning

6.3

0.4

Barrel Finishing

0.8

0.2

Electrolytic Grinding

0.6

0.2

Roller Burnishing

0.4

0.2

Grinding

1.6

0.1

Honing

0.8

0.1

Electrode-Polish

0.8

0.1

Polishing

0.4

0.1

Lapping

0.4

0.5

Super Finishing

0.2

0.025

Sand Casting

25

12.5

Hot Rolling

25

12.5

Forging

12.5

3.2

Perm. Mold Casting

3.2

1.6

Investment Casting

3.2

1.6

Extruding

3.2

0.8

Cold Rolling, Drawing

3.2

0.8

Die Casting

1.6

0.8