Chapter 19

Question 1

What is a non-traditional process? Why need it. (3)

Answer 1

processes that do not use a cutting tool.

for hard to machine metals and non-metals.
Diff geometries.
No surf damage

Question 2

Explain Ultrasonic Machining. What for? (3)

Answer 2

slurry with abrasives. tool vibrate. Fed slowly. Shape of tool.

hard brittle work. And ss and ti
shapes non-round and along curved axis.
coining.

Question 3

Water jet Cutting. What for? (3). Benefits (4)

Answer 3

high p and v water.

CNC.
Narrow slits in flat stock.
NOT brittle material

no crush or burning.
min material loss
no pollution
automated

Question 4

Abrasive water jet cutting (3). What for?

Answer 4

wjc with abrasives ranging 60 to 120.
Made from alumina, SiO2, garnet
Mass flow = 0.25 kg/min

Operator controlled.
Finishing process.
Deburring, trimming, polishing
hard brittle material and thin flat stock

Question 5

What are the adv(4)/disadv(4) of Water jet machining

Answer 5

Adv
work any hardness
any direction
no deburring
no thermal stresses

Disadv
nozzle life short
high cap cost of equip
very noisy

Question 6

Abrasive flow machining. What for (2)

Answer 6

Viscoelastic polymer (putty) with abrasive

Deburring and polishing difficult to reach areas (passageways)

Question 7

Electrochemical processes

Answer 7

reverse electroplating. Corrosion.

ECM, ECD. ECG

Question 8

Electrochemical machining. Tool material. what for? (3)

Answer 8

anodic dissolution and electrode.Deplates work. Tool: cu, brass, ss

Die sinking
multiple hole drilling (nonround holes)
deburring

Question 9

electrochemical deburring

Answer 9

removes burrs or sharp corners

Question 10

electrochemical grinding
what for (2)
benefits(2)

Answer 10

conductive bond material corrodes metal part surface

sharpening cemented carbide tools
grinding fragile parts

deplating 95% metal removal
grinding wheel lasts longer

Question 11

thermal energy processes problems

Answer 11

since removed from fusion or vaporization there is physical and metallurgical damage to work surface. bad finish

Question 12

Electric discharge machining
work materials (3)

Answer 12

shape of work made by shape of electrode tool.
requires dielectric fluid.

electrically conducting work
any hardness and strength of work
mrr depends on tm of work

Question 13

wire edm

what for? (2)

Answer 13

fed slowly. constant diameter. dielectric required with nozzles at interface.

stamping die components
intricate outline shapes like lathe form tools, extrusion dies, and flat templates

Question 14

electron beam machining
what for (3)

Answer 14

electrons at 75% c to melt in very localized area
reduce diameter by 0.025 mm

any material
micromachining
drilling holes with high depth to diameter ratios of 100:1

Question 15

ebm
adv (4)
disadv (5)

Answer 15

any material
no stresses imposed
fast drilling speed and precision
little material wasted with kerf

need skilled labor
need good backing material
max thick 10 mm
vacuum needed
capital equip high

Question 16

laser beam machining
what for (4)

Answer 16

monochromatic (single wave length)
highly collimated (light rays are almost perfectly parallel)
high power densities

drilling, slitting, slotting, scribing, marking
0.025 diam holes
used on thin stock
for high hardness and strength, soft metals, ceramics, glass….

Question 17

steps in chemical machining (4)

Answer 17

cleaning
masking: maskant chemically resistant
etching
demasking

Question 18

factors that determine Etchant

Answer 18

work material
depth and mrr
surface finish requirement

Question 19

process of chemical milling

Answer 19

clean raw part
apply maskant
scribe, cut, peel maskant
etch
remove maskant

Question 20

chemical milling for?

Answer 20

large amounts of metal are removed