General Information for Stainless Steel 303
| Material Group |
M - Stainless Steel |
| Sub-Group |
Austenitic Stainless Steel |
| Tensile Strength |
500-700 [N/mm^2] |
| Machinability Range |
72% |
MACHINABILITY OF 303 STAINLESS STEEL
303 is a free-machining stainless alloy providing the best machinability among the austenitic stainless alloys. It is primarily used on Swiss-type Machines (Screw Machines) when productivity is a crucial factor. The machinability rating is approximately 75%.
The sulfur addition, which is accountable for the enhanced machinability in 303 stainless, decreases its corrosion resistance and toughness to below that of 304 and 316 alloys.
It has 1.5% carbon (compared to around 0.08% in 304/316); thus, it is less soft, therefore less likely to develop 'build-up edge’, and is more manageable with chip control.
SUMMARY:
For general Turning of Stainless Steel 303 at stable conditions use a grade with a Semi Hard substrate and Thin CVD coating.
In case you are running at a cutting speed that is lower than 390 SFM (120 m/min), it is better to use a grade with a Semi Hard substrate and PVD coating.
For general Milling use a grade with a Semi Hard substrate and Thin PVD coating.
For detailed carbide grades recommendations,check the table below.
Recommended cutting speed range for turning at stable conditions is 890 - 1180 [SFM] / 270 - 360 [m/min].
Recommended cutting speed range for milling with stable clamping and short over hang is 560 - 750 [SFM] / 170 - 230 [m/min]
For detailed cutting speed recomendations, check the table below.
Equivalent International Designations for Stainless Steel 303
| Standard |
Name |
| sae |
303 |
| wnr |
1.4305 |
| din |
X8CrNiS18-9 |
| bs |
303S21, 58M |
| ss |
2346 |
| anfor |
Z10CNF18.09 |
| uni |
X10CrNiS 18.09 |
| unf |
F.3508 |
| js1 |
SUS303 |
Chemical Composition for Stainless Steel 303
| Element |
Amount |
| Chromium (Cr) |
19.5% |
| Nickel (Ni) |
10.5% |
| Silicon (Si) |
2.00% |
| Manganese (Mn) |
1.50% |
| Molybdenum (Mo) |
0.60% |
| Carbon (C) |
0.16% |
| Phosphorus (P) |
0.04% |
| Sulfur (S) |
0.30% |
Cutting Speeds Recomendations for Stainless steel - 303
| Application |
Vc (m/min) |
Vc (SFM) |
| Turning |
270-360 |
890-1180 |
| Milling |
170-230 |
560-750 |
| Parting |
105-145 |
340-480 |
| Grooving |
160-215 |
520-710 |
| Drilling |
75-105 |
250-340 |
Important! The speed estimation is given for an ideal situation:
- Most suitable carbide grade
- Stable tool clamping
- Stable workpiece clamping
- Good quality raw material
- A short overhang of the cutting tool.
- Nominal hardness of the material.
- etc.
Recommended Carbide Grades for Stainless Steel 303
Grade for Milling (Indexable)
Recommended Insert Cutting Edge Geometry for Stainless Steel 303
| Honing Size |
0.03-0.05 mm / 0.001-0.002" |
| Rake Angle |
9°-11° |
| Land Angle |
Positive |
| Land Width |
0.20-0.30 mm / 0.008-0.012" |
