When measuring a material’s hardness, there are various scales you may come across and need to convert from one to another. These different scales measure hardness in different ways. Generally, they aim to provide a measurement of the same thing: the ability of that material to resist permanent indentation from an external force. The Vickers scale is a measurement used commonly in industries such as metalworking, healthcare, and dentistry.
I. What is Vickers Hardness?
The Vickers hardness test uses an optical method to measure the relative resistance of a material to indentation with a diamond indenter. A Vickers indenter, a square base diamond point with a sharp tip, is pressed onto the material’s surface at a specified force and depth, causing the sample material to be indented. The depth of these marks is measured and recorded. From this reading, an average value is determined and reported as the Vickers hardness.
II. What is Brinell Hardness?
Brinell Hardness is another scale used widely in the industry for measuring the hardness of materials. This test is used for measuring materials with a rough surface; no other method can be used to measure the material. Brinell hardness test uses an instrument called a Brinell tester, which consists of a carbide tungsten ball of a specific diameter. When this ball is pushed into the sample material at a specified force, the depth and diameter of the indentation left behind are measured to determine the Brinell hardness number.
III. What is the Difference between Vickers and Brinell Hardness?
Vickers Hardness is measured by the depth at which a material is indented with a diamond point. Brinell Hardness, however, is determined by the size of an indentation left on the surface of the material after being pressed with a carbide tungsten ball.
Vickers hardness test measures materials with small parts or thin sections. In contrast, the Brinell hardness is used to measure materials with a rough surface and other unsuitable methods.
Related Article: What are the Advantages and Disadvantages of the Vickers Method?
Related Article: What are the Advantages and Disadvantages of the Brinell Method?
IV. Why Vickers and Brinell Hardness Test Results Show Similarities?
Though the Vickers and Brinell hardness scale measure different things, the results from these tests often show similar values. This is because both methods use a microscope to measure the indentations made. Both these methods use the ASTM standards. This might lead to similarities in results.
V. Vickers to Brinell Hardness Conversion Chart
Vickers (HV) | Brinell (10mm, 3000 kg) | |
Ball Indentation (d in mm) | Ball W. carb. HB | |
880 | – | 767 |
860 | – | 757 |
840 | 2.25 | 745 |
820 | – | 733 |
800 | – | 722 |
782 | 2.30 | 712 |
780 | – | 710 |
760 | – | 698 |
740 | – | 684 |
737 | 2.35 | 682 |
720 | – | 670 |
700 | – | 656 |
697 | 2.40 | 653 |
690 | – | 647 |
680 | – | 638 |
670 | – | 630 |
667 | 2.45 | 627 |
640 | 2.50 | 601 |
615 | 2.55 | 578 |
591 | 2.60 | 555 |
569 | 2.65 | 534 |
547 | 2.70 | 514 |
528 | 2.75 | 495 |
508 | 2.80 | 477 |
491 | 2.85 | 461 |
472 | 2.90 | 444 |
455 | 2.95 | 429 |
440 | 3.00 | 415 |
425 | 3.05 | 401 |
410 | 3.10 | 388 |
396 | 3.15 | 375 |
383 | 3.20 | 363 |
372 | 3.25 | 352 |
360 | 3.30 | 341 |
350 | 3.35 | 331 |
339 | 3.40 | 321 |
328 | 3.45 | 311 |
319 | 3.50 | 302 |
309 | 3.55 | 293 |
301 | 3.60 | 285 |
292 | 3.65 | 277 |
284 | 3.70 | 269 |
276 | 3.75 | 262 |
269 | 3.80 | 255 |
261 | 3.85 | 248 |
253 | 3.90 | 241 |
247 | 3.95 | 235 |
241 | 4.00 | 229 |
234 | 4.05 | 223 |
228 | 4.10 | 217 |
222 | 4.15 | 212 |
218 | 4.20 | 207 |
212 | 4.25 | 201 |
207 | 4.30 | 197 |
202 | 4.35 | 192 |
196 | 4.40 | 187 |
192 | 4.45 | 183 |
188 | 4.50 | 179 |
182 | 4.55 | 174 |
178 | 4.60 | 170 |
175 | 4.65 | 167 |
171 | 4.70 | 163 |
163 | 4.80 | 156 |
156 | 4.90 | 149 |
150 | 5.00 | 143 |
143 | 5.10 | 137 |
137 | 5.20 | 131 |
132 | 5.30 | 126 |
127 | 5.40 | 121 |
122 | 5.50 | 116 |
117 | 5.60 | 111 |
Conclusion
The Vickers hardness test measures materials with small parts or thin sections. In contrast, the Brinell hardness is used to measure materials with a rough surface, and other methods are unsuitable. The Vickers to Brinell conversion chart can help you convert values between the Vickers and Brinell hardness scales. This conversion chart contains valid data for commonly used materials in industries such as metalworking, healthcare, and dentistry. Other than metals, other materials that may be measured using the Vickers hardness test are ceramics, stone, wood, and leather.