|
MACHINING OPERATIONS, (CONT.)
Milling There are two important factors
to consider when milling niobium and its alloys: first, selecting
a good cutting fluid, and also using the proper tool design.
It is best to use a 0 axial rake angle and a positive 40 radial
rake angle. Data for specific milling operations is listed
in Tables 5 Ð 10.
TABLE 5: FACE MILLING OF NIOBIUM
| |
|
Carbide Tool |
|
|
High
Speed
Steel Tool
|
|
| DEPTH
OF CUT
in
(mm)
|
TOOL
MATERIAL
AISI
(ISO)
|
SPEED
fpm
(m/min)
|
FEED
PER TOOTH
in
(mm)
|
TOOL
MATERIAL
AISI
(ISO)
|
SPEED
fpm
(m/min)
|
FEED
PER TOOTH
in
(mm)
|
| 0.040
|
C-2
|
150-165
|
0.006
|
T15,
M42 |
100
|
0.005
|
| 0.150
|
C-2
|
140-155
|
0.008
|
T15,
M42 |
80
|
0.007
|
| (1.0)
|
(K10,
M20) |
(46-50)
|
(0.15)
|
(S9,
S11) |
(30)
|
(0.13)
|
| (4.0)
|
(K10, M20) |
(43-47)
|
(0.20)
|
(S9,
S11) |
(24)
|
(0.18)
|
TABLE 6: SLAB MILLING OF NIOBIUM
|
DEPTH OF CUT
in
(mm)
|
TOOL MATERIAL
AISI
(ISO)
|
SPEED
fpm
(m/min)
|
FEED PER TOOTH
in
(mm)
|
| 0.040
|
M2,
M7 |
70
|
0.004
|
| 0.150
|
M2,
M7 |
60
|
0.004
|
| (1.0)
|
(S4,
S2) |
(21)
|
(0.102)
|
| (4.0)
|
(S4,
S2) |
(18)
|
(0.102)
|
TABLE 7: HOLLOW MILLING OF NIOBIUM
| TOOL
MATERIAL |
SPEED
|
FEED
|
| AISI
or C |
fpm
|
ipr
|
| (ISO)
|
(m/min)
|
(mm/r)
|
| M2,
M7 |
40
|
0.004
|
| C-2
|
110
|
0.008
|
| (S4,
S2) |
(12)
|
(0.102)
|
| (K20)
|
(34)
|
(0.20)
|
Four of Eleven 1
2 3
4 5 6
7 8
9 10
11
|
