Hardness Conversion Calculator (HRC, HB, HV and HRB)

Q1. How accurate is this hardness conversion tool?

Our calculator is based on standard empirical data, such as ASTM E140 and ISO 18265. While these conversions are highly reliable for general engineering and material verification, they are considered “approximations.” For critical certification, always refer to the actual test results on your Material Test Report (MTR).

Q2. Can I use this calculator for all types of metal?

Hardness conversion relationships change based on the material’s elastic modulus. This tool is optimized for stainless steel, carbon steel, and nickel alloys. Using it for very soft metals like aluminum or extremely specialized titanium grades may require specific conversion tables unique to those alloys.

Q3. What is the difference between Brinell (HB) and Vickers (HV)?

Brinell (HB): Uses a heavy load and a ball indenter; ideal for materials with a coarse or irregular grain structure, like castings or forgings.

Vickers (HV): Uses a diamond pyramid indenter; it is highly precise and used for almost all metal hardness ranges, especially for thin sections and precision-machined parts.

Q4. Why are my results slightly different from printed tables?

Minor variances occur because different standards (ASTM vs. ISO) use slightly different mathematical models for curve fitting. Furthermore, the rounding of decimal points in various regional standards can lead to small discrepancies.

Q5. Why aren’t all alloys listed in the selection?

Hardness is a physical property of the specific heat treatment and cold-work state of the metal, not just the alloy itself. We provide the most common industrial conversions used for 304/316L stainless, Duplex 2205, and Inconel alloys.

Q6. Can I export these values for my Inspection Report?

Yes. The results are formatted to be easily copied and pasted into your Internal Quality Control (IQC) documents, quotations, or technical datasheets.

Q7. What if my project requires pressure-rated or code-compliant work?

For projects governed by ASME Pressure Vessel Codes or NACE MR0175 (sour service), hardness limits are strictly regulated. In these cases, you must use the direct test method specified by the code (e.g., HRC max 22 for certain NACE applications) rather than relying solely on a conversion.