Metal Cutting

1
Metal Cutting

• Manufacturing Processes

2
Outline

• Metal Cutting
• Chip Formation Processes
• Control
• Conditions
• Back rake angle
• Shear angle
• Chip Formation
• Continuous formation
• Built up edge formation
• Discontinuous formation
• Effects
• Chip formation
• Shear angle

3
Chip Formation Processes

• Shaping
• Turning
• Milling
• Drilling
• Sawing
• Broaching
• Grinding

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Machining Operations
5
Machining Operations
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Machining Operations - Sawing
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Machining Operations - Grinding
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Basic Cutting Face Cutting
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Basic Cutting Pocket Cutting
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Basic Cutting Turning Diameters
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Basic Cutting Thread Cutting
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Basic Cutting Surface Grinding
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Chip Formation Processes

• Control
• Feed
• Speed
• Depth of Cut
• Conditions
• Machining Process
• Machine Limitations
• Material
• Tool Type
• Tool material
• Surface Finish
• Tolerances

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Chip Formation Processes

• Back rake angle, a
• The angle that the tool makes with respect to a
  vertical from the workpiece
• The chip is formed by shearing along the shear
  plane
• The shear plane or shear angle F is measured with
  respect to the horizontal
• Flank of the tool is the bottom of the tool not
  in contact with the material (clearance angle d)

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Cutting Definitions
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Chip Formation
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ContinuousChip Formation
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Built Up Edge(BUE) Formation
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DiscontinuousChip Formation
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Chip Formation

• Three Characteristic types of chips
• Discontinuous
• Continuous
• Continuous with built-up edge

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Three Types of Chips
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Resulting Finishes of Chip Formation
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Effect of Shear Angle
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Summary

• Chip formation processes are designed to shear
  off layers of metal
• Control and conditions determine the type of chip
  formation
• The type of formation affects the resulting
  finish of the workpiece

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The End