While measuring the hardness value of materials in the manufacturing industry, changing scales is a common process. ASTM and ISO have provided many standardized conversion scales to help the manufacturing industry. Vickers hardness test is a micro testing method used for some specified cases. Sometimes it becomes necessary to change the hardness value from one scale to another. Here we compare the Vickers hardness method with the Rockwell method and their conversion charts.
I. What is Vickers Hardness?
The Vickers hardness test is represented by (HV). The test is the method to measure the hardness of thin sections or small parts of materials. The test proceeds by throwing the light load on the material test surface to produce penetration to create an indentation. The intender used in this method is diamond. The depth of the indentation then determines the value of the hardness. Generally, in the Vickers hardness test, the material to be tested is harder if the indentation is small.
II. What is Rockwell Hardness?
The Rockwell hardness test is represented by (HR) and has four types: HRC, HRA, HRB, and HRD. The Rockwell hardness test is performed by measuring the depth of indenter caused by throwing the heavy load on the material testing surface, causing penetration. In this case, the intender can be a diamond and also a steel ball.
Related Article: What are the Advantages and Disadvantages of the Rockwell Method?
Related Article: What are the Advantages and Disadvantages of the Vickers Method?
III. What is the Difference between Vickers and Rockwell Hardness?
The Vickers hardness test is a macro and microhardness testing method, while the Rockwell test is used only as a macro testing method. The Rockwell test is a quick and direct process, while the Vickers hardness test is a slow process and requires other optical devices such as a microscope to measure the hardness of the object.
Related Article: Hardness Test Comparison: Vickers vs Rockwell
Related Article: What is the Difference between Rockwell, Brinell, and Vickers?
IV. Vickers to Rockwell Hardness Conversion Chart
Vickers Hardness Test (HV) | Rockwell Hardness Test | |||
| (HRC) C scale | (HRA) A 60kgf diamond conical indenter | (HRB) B 100kgf diameter 1.6mm (1/16ln) ball | (HRD) D 100kgf diamond conical indenter |
940 900 865 832 800 772 746 720 697 674 653 633 613 595 577 560 544 528 513 498 484 471 458 446 434 423 412 402 392 382 372 363 354 345 336 327 318 310 302 294 286 279 272 266 260 254 248 243 238 230 222 213 204 196 188 180 173 166 160 | 68 67 66 65 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 24 23 22 21 20 (18) (16) (14) (12) (10) (8) (6) (4) (2) (0) | 85.6 85.0 84.5 83.9 83.4 82.8 82.3 81.9 81.2 80.7 80.1 79.6 79.0 78.5 78.0 77.4 76.8 76.3 75.9 75.2 74.7 74.1 73.6 73.1 72.5 72.0 71.5 70.9 70.4 69.9 69.4 68.9 68.4 67.9 67.4 66.8 66.3 65.8 65.3 64.7 64.3 63.8 63.3 62.8 62.4 62.0 61.5 61.0 60.5 – – – – – – – – – – | – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – (109.0) (108.5) (108.0) (107.5) (107.0) (106.0) (105.5) (104.5) (104.0) (103.0) (102.5) (101.5) (101.0) 100.0 99.0 98.5 97.8 96.7 95.5 93.9 92.3 90.7 89.5 87.1 85.5 83.5 81.7 | 76.9 76.1 75.4 74.5 73.8 73.0 72.2 71.5 70.7 69.9 69.2 68.5 67.7 66.9 66.1 65.4 64.6 63.8 63.1 62.1 61.4 60.8 60.0 59.2 58.5 57.7 56.9 56.2 55.4 54.6 53.8 53.1 52.3 51.5 50.8 50.0 49.2 48.4 47.7 47.0 46.1 45.2 44.6 43.8 43.1 42.1 41.6 40.9 40.1 – – – – – – – – – – |
Conclusion
Rockwell Hardness test is the most widely used method but in some cases Vickers Hardness testing method has to be used especially when thin parts have to be tested. It is important to look up the hardness scale standardized by ISO and ASTM while performing any hardness test to get accurate and reliable results. If you want to know more about the hardness methods, their procedures and conversion scales then visit our website and find answers for your questions.