A **hardness conversion calculator** is a specialized tool designed to convert hardness values between different scales used in material science and engineering.

**Hardness** is a crucial property of materials, indicating their resistance to permanent deformation under applied force. Various hardness scales exist, each suited for specific materials or **testing conditions**.

The most common scales include:

**Rockwell (HRA, HRB, HRC)****Brinell (HB)****Vickers (HV)****Shore (HS)**

The **hardness conversion converter** allows engineers and materials scientists to easily translate values from one scale to another, facilitating comparison and analysis across different testing methods.

**Sample conversions:**

**Rockwell C (HRC) to Brinell (HB):**

A steel sample with a hardness of 40 HRC can be converted to approximately 371 HB.

**Vickers (HV) to Rockwell B (HRB):**

A brass specimen with a hardness of 150 HV is equivalent to about 82 HRB.

**Brinell (HB) to Vickers (HV):**

An aluminum alloy with a hardness of 100 HB corresponds to roughly 105 HV.

## Hardness Conversion Calculator

Original Scale | Original Value | Target Scale | Converted Value | Conversion Equation |
---|---|---|---|---|

HRC | 40 | HB | 371 | HB ≈ 10.6 * HRC + 47 |

HB | 300 | HRC | 31.8 | HRC ≈ -0.000000567 HB^2 + 0.0624 HB – 13.7 |

HV | 500 | HRC | 49.1 | HRC ≈ -0.0000172 HV^2 + 0.245 HV – 2.87 |

HRB | 90 | HV | 185 | HV ≈ 1.0483 * HRB + 36.5 |

HB | 200 | HV | 210 | HV ≈ 1.05 * HB |

HRC | 55 | HV | 600 | HV ≈ 20 * HRC – 500 |

HB | 400 | HRB | 110 | HRB ≈ 0.0556 * HB + 87.8 |

HV | 300 | HB | 286 | HB ≈ 0.95 * HV |

## Hardness Conversion Formula

**Y = aX^2 + bX + c**

Where:

**Y**is the hardness value in the target scale**X**is the hardness value in the original scale**a**,**b**, and**c**are constants determined through empirical testing

Example: Converting **Brinell (HB) to Rockwell C (HRC)** for steels:

**HRC = -0.000000567 HB^2 + 0.0624 HB – 13.7**

Using this formula, we can convert a **Brinell hardness** of 300 HB to **Rockwell C**:

HRC = -0.000000567 *300^2 + 0.0624* 300 – 13.7

≈ 31.8 HRC

**Hardness conversion formulas** are typically empirical relationships derived from extensive testing and data analysis. These formulas are often specific to certain material types or hardness ranges.

## How do you convert Rockwell hardness?

Converting **Rockwell hardness** involves using specific formulas or tables designed for the particular **Rockwell scale (A, B, C, etc.)** and the target hardness scale. The process typically follows these steps:

**Identify the Rockwell scale:**Determine which**Rockwell scale (e.g., HRA, HRB, HRC)**the original measurement is in.**Choose the target scale:**Decide which hardness scale you want to convert to (e.g.,**Brinell, Vickers**).**Use a conversion formula or table:**Apply the appropriate formula or consult a conversion table to transform the value.**Consider material type:**Ensure the conversion is valid for the specific material being tested.

For example, to convert from **Rockwell B (HRB) to Vickers (HV)** for a copper alloy:

**HV ≈ 1.0483 * HRB + 36.5**

If we have a **Rockwell B hardness** of 70 HRB:

HV ≈ 1.0483 * 70 + 36.5

≈ 110 HV

## What is the formula for hardness measurement?

Here are formulas for three common hardness tests:

**Brinell Hardness (HB):**

**HB = 2F / (πD(D – √(D^2 – d^2)))**

Where:

**F**is the applied force (in kgf)**D**is the diameter of the indenter (in mm)**d**is the diameter of the indentation (in mm)**Vickers Hardness (HV):**

**HV = 1.8544 * F / d^2**

Where:

**F**is the applied force (in kgf)**d**is the average length of the diagonals of the indentation (in mm)**Rockwell Hardness:**

The **Rockwell hardness** is calculated based on the depth of indentation. The general formula is:

**HR = E – e**

Where:

**E**is a constant depending on the indenter form**e**is the permanent increase in indentation depth (in units of 0.002 mm)

The specific constants and procedures vary for different **Rockwell scales (A, B, C, etc.)**.

## What is the ISO standard for hardness conversion?

The **International Organization for Standardization (ISO)** has established several standards related to hardness testing and conversion. The primary standard for hardness conversion is:

**ISO 18265:2013 – Metallic materials – Conversion of hardness values**

This standard provides guidelines and tables for converting hardness values between various scales, including:

**Vickers hardness****Brinell hardness****Rockwell hardness (scales A, B, C, D, E, F, G, H, K, N, T)****Knoop hardness****Leeb hardness**

The standard covers conversion relationships for different material groups, such as unalloyed and low-alloy steels, tool steels, and cast irons. It also includes information on the accuracy and limitations of these conversions.

**ISO 18265:2013** emphasizes that these conversions are approximate and should be used with caution, especially when dealing with materials that have undergone special heat treatments or manufacturing processes.

## How to convert HBW to HRC?

Converting from **Brinell hardness (HBW) to Rockwell C hardness (HRC)** is a common requirement in material testing. The conversion process typically involves using empirical formulas or standardized conversion tables.

Here’s a general approach:

**Use a conversion formula:**

For steels, a commonly used formula is:

**HRC ≈ -0.000000567 HBW^2 + 0.0624 HBW – 13.7**

**Consult conversion tables:**

Reference **ISO 18265:2013** or other standardized conversion tables for more accurate results across different material types.

**Consider material-specific formulas:**

For certain alloys or heat-treated materials, specialized formulas may be more accurate.

**Use a hardness conversion calculator:**

Many online tools and software applications can perform this conversion quickly and accurately.

Example conversion:

Let’s convert a **Brinell hardness** of 350 HBW to **Rockwell C**:

HRC ≈ -0.000000567 *350^2 + 0.0624* 350 – 13.7

≈ 37.3 HRC