Description
Alloy Geek 303 Austenitic Stainless Steel Standard
303 Stainless Steel is a popular austenitic stainless steel alloy, optimized for high machinability and corrosion resistance. It is non-magnetic in the annealed condition and suitable for applications that require excellent toughness and wear resistance. It's enhanced by adding sulfur and phosphorus, which improve its machining properties without severely affecting its corrosion resistance and mechanical properties. It is widely used in the aerospace, automotive, and industrial sectors for parts that require grinding, machining, and polishing.
Chemical Composition (weight %):
| Element | Min (%) | Max (%) |
|---|---|---|
| Carbon | - | 0.15 |
| Manganese | - | 2.00 |
| Phosphorus | - | 0.20 |
| Sulfur | 0.15 | - |
| Silicon | - | 1.00 |
| Chromium | 17.00 | 19.00 |
| Nickel | 8.00 | 10.00 |
| Iron | Bal. | - |
Key Properties:
- Austenitic Microstructure: Non-magnetic in the annealed condition, with a face-centered cubic crystal structure.
- Enhanced Machinability: Contains sulfur and phosphorus for improved machinability.
- Corrosion Resistance: Resists atmospheric corrosion, as well as moderate alkaline and reducing environments.
- Toughness and Wear Resistance: Suitable for applications that require these attributes.
Other Names for 303 Stainless Steel:
- A1 Stainless Steel
- 18-8 Chromium-Nickel Steel
- S30300 (UNS Designation)
303 vs. 304 Stainless Steel: 303 Stainless Steel is specifically designed for improved machinability, thanks to the addition of sulfur and phosphorus, which are not present in 304 stainless steel. While 304 offers higher corrosion resistance, the presence of these free-machining elements in 303 makes it the preferred choice for parts that require significant machining. However, 303 is less readily available in sheet and plate forms and is not recommended for applications requiring welding, whereas 304 stainless steel is more versatile and widely used for welded constructions.
XRF standards are thin samples typically around 1/4" thick while OES standards are typically much thicker to allow for sample preparation.
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In summary, the main difference between a reference material and a certified reference material lies in the level of characterization, validation, and certification. CRMs have undergone a more comprehensive and rigorous testing process, resulting in certified values and uncertainties that can be confidently used for instrument calibration, quality control, and research. Reference materials, on the other hand, can provide a point of comparison but do not have the same level of certification and traceability as CRMs. When accuracy and traceability are critical, certified reference materials are preferred.