Scleroscope hardness scale

Scleroscope hardness numbers are convertible to other hardness scales (see ASTM E140) (2). 

Brinefl Indentation Dla(mm) Brinell Hardness Nunber C-Scale 15-N Scale 30-N Scale 45-N Scale 45-lui Load Shore Scleroscope Hardness Approximate Tensile Strenath (ksi)... 

The Scleroscope scale ranges from 0 to 140 the cahbration point of 100 is the hardness of fully quenched but untempered steel. Standard test blocks embodying this condition are used for cahbration. 

Other methods of determining the hardness of a material include a variety of "penetration" tests that yield hardness values measured in scales known as the Brinell, Rockwell (B or C), and scleroscope scales. These scales provide reliable hardness values for most materials, including ceramics, glass, metals and alloys, and wood (see Table 21). Unfortunately, as can be seen in the table, the various tests provide somewhat different hardness values for the same materials. 

The so-called Shore hardnesses are measured differently for metals and plastics. With hard materials (metals), a scleroscope is used to measure the rebound of a small steel ball. This Shore hardness is thus measured by a dynamic method, which yields the rebound hardness (the impact elasticity of the rubber industry). Soft plastics, on the other hand, are tested with a Shore durometer. This measures the resistance to the penetration of the point of a cone through the contraction of a calibrated spring. The durometer thus works according to a static method, and yields the true Shore hardness as understood by the rubber industry. Like the Rockwell hardness, the Shore hardness is given in scale divisions. 

Hardness -nos n (before 12c) (1) The resistance to local deformation. (2) Ability of a coating film, as distinct from its substrate, to resist cutting, indentation, or penetration by a hard object. An arbitrary scale of hardness is based upon ten selected minerals. For metals the diameter of the indentation made by a hardened steel sphere (Brinnell) or the height of rebound of a small drop hammer (Shore Scleroscope) serve to measure hardness. See Barcol Hardness, Brinell Hardness, Durometer, Indentation Hardness, Knoop Hardness Number,... 

Hardness is a measurement of material resistance to plastic deformation in most cases. It is a simple nondestructive technique to test material indentation resistance, scratch resistance, wear resistance, or machinability. Hardness testing can be conducted by various methods, and it has long been used in analyzing part mechanical properties. In reverse engineering, this test is also widely used to check the material heat treatment condition and strength, particularly for a noncritical part, to save costs. The hardness of a material is usually quantitatively represented by a hardness number in various scales. The most utilized scales are Brinell, Rockwell, and Vickers for bulk hardness measurements. Knoop, Vickers microhardness, and other microhardness scales are used for very small area hardness measurements. Rockwell superficial and Shore scleroscope tests are used for surface hardness measurements. Surface hardness can also be measured on a nanoscale today. 

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