Chapter 21

Question 1

the angle that the tool makes with respect to a vertical from the workpiece.

Answer 1

Back rake angle-

Question 2

where a reduced lead angle or a less round (and smaller nose radius compared to DOC) inserts maintains more axial (stiffer tool direction) orientation of Y, leading to greater stability.

Answer 2

Boring-

Question 3

one of the seven basic machining processes in chip formation. Broach, cutting tool moves into work, and work stationary are the machine areas.

Answer 3

Broaching-

Question 4

the most common metal cutting example due to the regeneration of surface waving. Part of self-excited vibration in machining.

Answer 4

Chatter-

Question 5

a variation of continuous chip, often encountered in machining ductile materials.

Answer 5

Built-up edge (BUE) -

Question 6

used to compute the shear angle. Defined as t/t_c. (page 499)

Answer 6

Chip ratio-

Question 7

the chip has a velocity/speed V_c.

Answer 7

Chip velocity-

Question 8

can cause the process-induced variation in the cutting force.

Answer 8

Cutting velocity-

Question 9

used interchangeably with the term specific energy U. A material property related to shear flow stress, hardness and work hardening and is often described in a relative sense of the machinability of materials.

Answer 9

Cutting stiffness (k_s) -

Question 10

used to machine the workpiece and is the most critical component.

Answer 10

Cutting tool-

Question 11

the distance the tool is plunged into the surface.

Answer 11

Depth of cut (DOC) -

Question 12

one of the 7 basic chip formation processes. A rotational multiple-edge tool process.

Answer 12

Drilling-

Question 13

is the amount of material removed per revolution pr per pass of the tool over the workpiece.

Answer 13

Feed (f_r) -

Question 14

what the resultant R is composed of along with the normal force N acting on the tool/chip interface contact area.

Answer 14

Friction force-

Question 15

one of the 7 basic chip formation processes. (Discussed in chapters 23-27).

Answer 15

Grinding (abrasive machine) -

Question 16

a stationary, power-driven machine used to cut, shape, or form materials such as metal and wood. (NOTE: this definition is from Britannica Concise Encyclopedia).

Answer 16

Machine tool-

Question 17

the process of removing unwanted material from a metal workpiece in the form of chips (often called metal removal).

Answer 17

Metal cutting-

Question 18

the process of milling requires two figures because it takes different forms depending upon the selection of the machine tool and the cutting tool; a multiple tooth process, has two feeds; has replaced shaping and planning

Answer 18

Milling-

Question 19

three-dimensional geometry; the cutting edge and the cutting motion are not perpendicular to each other

Answer 19

Oblique machining

Question 20

two dimensional geometry; done to test machining mechanics and theory; the cutting velocity vector and the cutting edges are perpendicular

Answer 20

Orthogonal machining

Question 21

caused by a phase shift between overlapping cutting paths; a self-excited vibration that is caused by the closed -loop displacement response of the machining process

Answer 21

Regenerative chatter

Question 22

a basic machining process in which chips are produced by a succession of small cutting edges, or teeth, arranged in a narrow line on a saw “blade”.

Answer 22

Sawing

Question 23

the periodic response of the system to a constant input

Answer 23

Self-excited vibration

Question 24

the work piece is fed at right angles to the cutting motion between successive strokes of the tool

Answer 24

Shaping

Question 25

the onset of the shear process takes place along the lower boundary of the shear zone defined by the shear angle (phi)

Answer 25

Shear angles

Question 26

can be found using sophisticated electronics and slow-motion playback

Answer 26

Shear velocity

Question 27

depends only on the rake angle (alpha) ; expressed as cosine of alpha divided by one plus the sine of alpha

Answer 27

Shear strain

Question 28

aka flow stress-is a material constant

Answer 28

Shear force

Question 29

values found experimentally using orthogonal machining

Answer 29

Specific horsepower

Question 30

primary cutting motion, which relates the velocity of the cutting tool relative to the work piece.

Answer 30

Speed

Question 31

relates the total width of cut that can be machined to the rotational speed of the tool with a specified number of cutting edges

Answer 31

Stability lobe diagram

Question 32

the process of machining external cylindrical and conical surfaces

Answer 32

Turning

Question 33

the mechanism by which a process dissipates energy

Answer 33

Vibration

Question 34

holds work pieces

Answer 34

work holding device

Question 35

held in work holding devices

Answer 35

work piece