Rigorous application of SI is a problem. However the kilogram can also be used. Newton (N) â This is the SI unit of force; the measure for tablet hardness tester machines. The one Iâm familiar with is Mohâs mineral hardness scale. Most Vickers hardness testing machines use forces of 1, 2, 5, 10, 30, 50 and 100 kgf and tables for calculating HV. BHN or Brinell Number is the numerical value assigned to the hardness of metals and alloys. mm â2 = 9.80665 MPa. Rigorous application of SI is a problem. Apatite 6. Kilogram (kg) â The kilogram is recognized by the SI system as the primary unit of mass. Newton (N) â The Newton is the SI unit of force and is the unit that should be used for tablet hardness testing. Covers the Rockwell C scale for hard materials. of Water is in UNIT of PPM Material Hadrness is measured into Brinnel hardness Number. it is define by number like brenell hardness number and vicker hardness number The Newton is the preferred unit of force as is recognized by the SI system. Newton (N) â The Newton is the SI unit of force; the standard for tablet hardness testing. ... SI Units Calculators for Conversion between Units of Measurement Hardness Testing Surface Engineering Message Board Archive 9.807 Newtons = 1 kilogram. Kilogram (kg) â SI system recognizes kilogram as the main unit of mass. 6 Yes : 0 No : what is the unit of hardness?.. A strong and ductile material will have high toughness. The Brinell scale characterizes the indentation hardness of materials through the scale of penetration of an indenter, loaded on a material test-piece. Talc 2. The Rockwell hardness number is not the same as the calculated depth differential measurement. Calcite 4. HV/30) value should normally be expressed as a number only (without the units kgf/mm 2). Vickers hardness (e.g. Rigorous application of SI is a problem. Orthoclase 7. Weighing tablets â Image source: WELWEB. The test was developed by Frederick Knoop  and colleagues at the National Bureau of Standards (now NIST ) of the United States in 1939, and is defined by the ASTM E384 standard. Pound (lb) â Basically pound is a unit of force though you can as well use it for mass under earth gravity. hardness no. The Rockwell hardness scale number appears inverse to the depth differential calculation. Quartz 8. It is one of several definitions of hardness in materials science. Some conditions, especially the incidence of cold work, can change the relationship between the tensile strength and hardness profoundly. Vickers hardness (e.g. Hardness conversion table - Tensile strength, Vickers, Brinell och Rockwell (According to DIN 50150) The information below is for guidance only and should not be seen as fixed reference values. Most Vickers hardness testing machines use forces of 1, 2, 5, 10, 30, 50 and 100 kgf and tables for calculating HV. Pound (lb) â Technically a unit of force but can also be used for mass under earth gravity. Softer metals allow for deeper penetration than harder metals, so the B â A value will always be higher on soft metal test subjects than hard metals. Answer / rohit. Kilogram (kg) â The kilogram is recognized by the SI system as the primary unit of mass. Hardness conversion between different methods and scales cannot be made mathematically exact for a wide range of materials. Just to add to the existing answer, toughness is defined as the amount of energy a material can absorb before fracture and has units of MJ/m3 . HV/30) value should normally be expressed as a number only (without the units kgf/mm 2). 9.807 Newtons = 1 kilogram (at one G, earth surface gravity). 9.807 Newton = 1 kilogram (at earth surface gravity). Fluorite 5. Different loads, different shape of indenters, homogeneity of specimen, cold working properties and elastic properties all complicate the problem. Hardness scale conversion table for finding approximate equivalent hardness on different scales. Gypsum 3. It rates minerals on a hardness scale of 1â10, with 1 being softest (talc) and 10 being hardest (diamond): 1. Rigorous application of SI is a problem. Is This Answer Correct ?