In materials science, hardness (antonym: softness) is a measure of the resistance to localized plastic deformation, such as an indentation (over an area)...

The Mohs scale (/moʊz/ MOHZ) of mineral hardness is a qualitative ordinal scale, from 1 to 10, characterizing scratch resistance of minerals through the...

benefits. It can pose critical problems in industrial settings, where water hardness is monitored to avoid costly breakdowns in boilers, cooling towers, and...

In computational complexity theory, a computational problem H is called NP-hard if, for every problem L which can be solved in non-deterministic polynomial-time...

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...

The Vickers hardness test was developed in 1921 by Robert L. Smith and George E. Sandland at Vickers Ltd as an alternative to the Brinell method to measure...

Carbonate hardness, is a measure of the water hardness caused by the presence of carbonate (CO2− 3) and bicarbonate (HCO− 3) anions. Carbonate hardness is usually...

Hardness scales may refer to: Scratch hardness The Mohs scale of mineral hardness The Vickers hardness test The Brinell scale The Janka hardness test The...

Vickers Hardness, Rockwell Hardness, Superficial Hardness, Knoop Hardness, Scleroscope Hardness, and Leeb Hardness" (2019) Hardness Conversion Table – Brinell...

The Janka hardness test (English: /ˈdʒæŋkə/; German: [ˈjaŋka]), created by Austrian-born American researcher Gabriel Janka (1864–1932), measures the resistance...

hardness of materials through the scale of penetration of an indenter, loaded on a material test-piece. It is one of several definitions of hardness in...

Indentation hardness tests are used in mechanical engineering to determine the hardness of a material to deformation. Several such tests exist, wherein...

engineering and metallurgy, hot hardness or red hardness (when a metal glows a dull red from the heat) corresponds to hardness of a material at high temperatures...

Scratch hardness refers to the hardness of a material in terms of resistance to scratches and abrasion by a harder material forcefully drawn over its...

The Shore durometer is a device for measuring the hardness of a material, typically of polymers. Higher numbers on the scale indicate a greater resistance...

relative ordering of ligands and transition metal ions in terms of their hardness and softness. HSAB theory is also useful in predicting the products of...

Hardness can vary by several hundred percent depending on the pretreatment, see e.g. Iron#Mechanical properties and Angelo Basile; Fausto Gallucci (2011)...

were then fired in a kiln. By varying the ratio of graphite to clay, the hardness of the graphite rod could also be varied. This method of manufacture, which...

The Knoop hardness test /kəˈnuːp/ is a microhardness test – a test for mechanical hardness used particularly for very brittle materials or thin sheets...

Tempering is usually performed after hardening, to reduce some of the excess hardness, and is done by heating the metal to some temperature below the critical...

Degrees of general hardness (dGH or °GH) is a unit of water hardness, specifically of general hardness. General hardness is a measure of the concentration...

hardness of approximation is a field that studies the algorithmic complexity of finding near-optimal solutions to optimization problems. Hardness of...

it at a negligible rate under those conditions. Diamond has the highest hardness and thermal conductivity of any natural material, properties that are used...

In computational complexity theory, a computational hardness assumption is the hypothesis that a particular problem cannot be solved efficiently (where...

Neue Deutsche Härte (German: [ˈnɔʏə ˈdɔʏtʃə ˈhɛʁtə]; lit. "New German Hardness"), sometimes abbreviated as NDH, is a subgenre of rock music that developed...

Look up hard in Wiktionary, the free dictionary. Hard may refer to Hardness, resistance of physical materials to deformation or fracture Hard water, water...

superhard material is a material with a hardness value exceeding 40 gigapascals (GPa) when measured by the Vickers hardness test. They are virtually incompressible...

cooled, which is the tempering phase. The hardness of abrasion resistant steel is determined by a Brinell hardness test. This test uses a small steel ball...

The Hardness of the World is the second album by the American funk band Slave, released in 1977, their second album release that year. The lead single...

The Erection Hardness Score (EHS) is a single-item Likert scale used to assess the subjective hardness of the penis as reported by the patient. It ranges...