Distinguishing between genuine and fake 304 stainless steel (i.e. whether it meets the 06Cr19Ni10 standard in GB/T 3280-2015 or the 304 standard in ASTM A240) requires comprehensive judgment through multiple methods. The following are common identification methods:

1. Chemical testing (most accurate)

Spectral analysis: By using a handheld X-ray fluorescence spectrometer (XRF) to detect the composition, genuine 304 stainless steel should meet the following requirements:

Chromium (Cr) content: 18%~20%

Nickel (Ni) content: 8%~10.5%

Carbon (C) content: ≤ 0.08%

Laboratory testing: precise analysis of components through chemical titration or ICP (inductively coupled plasma).

2. Magnetic testing (auxiliary judgment)

304 stainless steel belongs to austenitic stainless steel, usually non-magnetic or weakly magnetic (may have slight magnetism after cold working).

If the material exhibits strong magnetism, it may be counterfeit (such as using low nickel 201, 430 stainless steel to impersonate).

Attention: Magnetic testing cannot be used alone as a basis for judgment and should be combined with other methods

3. Liquid detection (fast but cautious)

Stainless steel identification solution (manganese detection):

After being dropped on the surface and electrified, if it turns red or pink, it may be 201 stainless steel with high manganese and low nickel (304 does not change color)

Caution: The solution may corrode the surface, and it should be cleaned promptly after testing

4. Surface identification

304 stainless steel produced by legitimate manufacturers usually has laser engraving or steel stamp markings, such as:

304, SUS304, 06Cr19Ni10

But the identification may be forged and needs to be verified through other methods

5. Observation of Physical Characteristics

Color: Genuine 304 with uniform surface gloss, presenting a matte or soft finish; Fake products may have a dark and uneven color

Corrosion resistance: 304 has strong rust resistance in salt spray environments, while materials such as 201 are prone to rusting (requiring long-term testing)

6. Certificate and Source

Require suppliers to provide material certification (MTC) or third-party testing reports

Choose legitimate channels (such as large steel mills or authorized distributors) to avoid low-priced and low-quality products

Common counterfeit materials

201 stainless steel: low nickel content (1%~1.5%), high manganese content (5.5%~7.5%), easy to rust

430 stainless steel: nickel free, chromium content of about 16%~18%, strong magnetic properties

Precautions

A single method may have errors, it is recommended to combine chemical and physical testing

Important uses (such as food equipment, medical devices) must be confirmed through professional testing

By using the above methods, the risk of purchasing counterfeit 304 stainless steel can be significantly reduced