PRODEC® 303 is a fully resulfurized free-machining austenitic stainless steel melted and processed to maximize machinability. It should be considered for automatic screw machines where extensive machining is required. PRODEC®303 is nonmagnetic in the annealed condition but may become slightly magnetic as a result of cold working.
PRODEC®303 is resistant to mildly corrosive atmospheres but is inferior to 304 because of the high sulfur content. For optimum corrosion resistance, it is recommended that PRODEC®303 be chemically treated to remove sulfides from the final surface of the parts.
The high sulfur content, added for machinability, is detrimental to hot workability. If hot forming is necessary, PRODEC®304 or an intermediate sulfur level should be considered. When forging is necessary, it should be done in the 1800-2200°F range, and should be followed by annealing at 1900°F minimum and water quenching or rapid cooling by other means.The cold formability of PRODEC®303 is limited by the sulfur content. Bending with a generous bend radius may be considered for PRODEC®303. When cold forming is required, PRODEC®304 should be considered.
PRODEC®303 is not recommended for applications requiring welding. The high sulfur level in PRODEC®303 makes it prone to weld solidification cracking. If welding is necessary, AWS E312 filler metal may be considered.
PRODEC®303 is easily machined and produces small brittle chips. PRODEC®303 may be machined at high speeds with deep cuts and heavy feeds on powerful, rigid equipment using good lubricants and sharp tooling.
Chemistry
|
|
Cr
|
Ni
|
C
|
Mn
|
P
|
S
|
Si
|
Fe
|
|
MIN
|
17.0
|
8.0
|
-
|
-
|
-
|
0.3
|
-
|
-
|
|
MAX
|
19.0
|
10.0
|
0.15
|
2.0
|
0.2
|
-
|
1.0
|
Balance
|
Prodec®303 contains 0.30% minimum sulfur for enhanced machinability, substantially higher than the 0.15% minimum required by ASTM
Specifications
Inventory
PRODEC®303 Hex Bar, PRODEC®303 Round Bar
Features
· Melted and processed to maximize machinability
· Improved machinability over 304/304L and 316/316L
Applications
· Automatic screw machines
Physical Properties
Density: 0.285 lb/inch3
Modulus of Elasticity: 29 x 106 psi
Linear Expansion 60-212°F: 9.4 x 10-6/°F
Thermal Conductivity: 8.7 Btu/ft hr °F
Heat Capacity: 0.12 Btu/lb °F
Electrical Resistivity: 27.6 Ω in x 10-6
Mechanical Properties
Typical Tensile Properties
|
Tensile Strength, ksi
|
90
|
|
Yield Strength, ksi
|
43
|
|
% Elonation in 2 inches
|
55
|
|
% Reduction of area
|
60
|
|
Hardness, HB
|
180
|
Machining
High Speed Tooling
|
|
Turning
|
Cut-Off
|
Forming
|
Drilling
|
Reaming
|
End Milling
|
Tapping
|
Threading
|
|
Depth/Width, (dia/in)
|
0.005-0.200
0.002-0.004
|
1/16
1/4
|
1
2
|
1/4
1/2
1-2
|
1/4
1-2
|
0.050-1/2
0.050-1/2
|
7 threads
per inch
|
25 threads
per inch
|
|
Speed, (sfm)
|
115-130
135-180
|
90-120
100-130
|
100-130
90-120
|
70-80
85-95
100-110
|
90-110
90-110
|
130-160
130-160
|
10-115
|
40-50
|
|
Feed, (in/rev)
|
0.015-0.02
0.005-0.01
|
0.0015-0.002
0.0025-0.003
|
0.0020
0.0015
|
0.007
0.012
0.020
|
0.006
0.025
|
0.003
0.006
|
-
|
-
|
Carbide Tooling
|
|
Turning
|
Cut-Off
|
Forming
|
Drilling
|
Reaming
|
End Milling
|
Tapping
|
Threading
|
|
Depth/Width, (dia/in)
|
0.005-0.200
0.002-0.004
|
1/16
1/4
|
1
2
|
1/4
1/2
1-2
|
1/4
1-2
|
0.050-1/2
0.050-1/2
|
7 threads
per inch
|
25 threads
per inch
|
|
Speed, (sfm)
|
375-700
600-900
|
275-400
325-450
|
375-425
350-400
|
700
800
|
-
-
|
300-450
360-500
|
-
|
-
|
|
Feed, (in/rev)
|
0.025-0.030
0.007-0.010
|
0.002-0.004
0.004-0.008
|
0.003-0.006
0.002-0.004
|
0.005
0.007
|
|
0.004
0.008
|
-
|
-
|
