enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Total dissolved solids - Wikipedia

    en.wikipedia.org/wiki/Total_dissolved_solids

    TDS = k e EC. where TDS is expressed in mg/L and EC is the electrical conductivity in microsiemens per centimeter at 25 °C. The conversion factor k e varies between 0.55 and 0.8. [5] Some TDS meters use an electrical conductivity measurement to the ppm using the above formula. Regarding units, 1 ppm indicates 1 mg of dissolved solids per 1,000 ...

  3. Hardness comparison - Wikipedia

    en.wikipedia.org/wiki/Hardness_comparison

    A variety of hardness-testing methods are available, including the Vickers, Brinell, Rockwell, Meyer and Leeb tests. Although it is impossible in many cases to give an exact conversion, it is possible to give an approximate material-specific comparison table for steels .

  4. Brinell scale - Wikipedia

    en.wikipedia.org/wiki/Brinell_scale

    The Brinell hardness is designated by the most commonly used test standards (ASTM E10-14 [2] and ISO 6506–1:2005) as HBW (H from hardness, B from brinell and W from the material of the indenter, tungsten (wolfram) carbide). In former standards HB or HBS were used to refer to measurements made with steel indenters.

  5. Table of thermodynamic equations - Wikipedia

    en.wikipedia.org/wiki/Table_of_thermodynamic...

    Formula Natural variables Internal energy (+),, {} Helmholtz free energy ... Thermodynamic equation calculator This page was last edited on 9 December 2024, at 23:05 ...

  6. Rockwell scale - Wikipedia

    en.wikipedia.org/wiki/Rockwell_scale

    A Rockwell hardness tester. The Rockwell scale is a hardness scale based on indentation hardness of a material. The Rockwell test measures the depth of penetration of an indenter under a large load (major load) compared to the penetration made by a preload (minor load). [1]

  7. Vickers hardness test - Wikipedia

    en.wikipedia.org/wiki/Vickers_hardness_test

    The unit of hardness given by the test is known as the Vickers Pyramid Number (HV) or Diamond Pyramid Hardness (DPH). The hardness number can be converted into units of pascals, but should not be confused with pressure, which uses the same units. The hardness number is determined by the load over the surface area of the indentation and not the ...

  8. Hardness - Wikipedia

    en.wikipedia.org/wiki/Hardness

    When testing coatings, scratch hardness refers to the force necessary to cut through the film to the substrate. The most common test is Mohs scale, which is used in mineralogy. One tool to make this measurement is the sclerometer. Another tool used to make these tests is the pocket hardness tester. This tool consists of a scale arm with ...

  9. Meyer hardness test - Wikipedia

    en.wikipedia.org/wiki/Meyer_hardness_test

    The Meyer hardness test is a hardness test based upon projected area of an impression. The hardness, H {\displaystyle H} , is defined as the maximum load, P max {\displaystyle P_{\text{max}}} divided by the projected area of the indent, A p {\displaystyle A_{\text{p}}} .