Mechanics of Chip Formation Flashcards
(15 cards)
What is chip formation in metal cutting?
The process where material is sheared, fractured, and flows into chips due to the cutting tool engaging the workpiece.
What are the three main mechanisms involved in chip formation?
Plastic deformation, friction, and ductile fracture.
Name the primary types of chips formed during metal cutting.
Continuous chips, discontinuous chips, lamellar chips, and chips with Built-Up Edge (BUE).
What type of chip is considered ideal for efficient cutting and good surface finish?
Continuous chip.
What type of material typically forms discontinuous chips?
Brittle materials, such as cast iron.
What is the rake angle in tool geometry?
The angle between the rake face and a line perpendicular to the workpiece.
How does a high rake angle affect cutting forces?
It decreases cutting forces by reducing resistance.
What is the chip compression ratio?
The ratio of chip thickness to uncut chip thickness, used to evaluate chip compaction.
What causes a Built-Up Edge (BUE) to form on the cutting tool?
Adhesion of material to the tool due to high pressure, temperature, and friction at the cutting interface.
How does cutting speed influence chip formation?
High cutting speeds generally produce continuous chips, while low speeds can result in discontinuous chips.
What is the difference between orthogonal and oblique cutting?
Orthogonal cutting involves a cutting edge perpendicular to the cutting direction, while oblique cutting has the edge at an angle.
What is the primary role of the clearance angle in a cutting tool?
To prevent the tool from rubbing against the machined surface, reducing friction and wear.
What determines the type of chip formed in a cutting operation?
Material properties, tool geometry, and cutting conditions (e.g., speed, feed, and lubrication).
Why are ductile materials more likely to form continuous chips?
Because their high ductility allows smooth plastic deformation without fracturing.
What is the shear plane in chip formation?
The plane where most of the plastic deformation occurs, separating the chip from the workpiece.
