Hardness Hardness Hardness is a measure of the resistance to localized plastic deformation induced by either mechanical indentation or abrasion. Some materials (e.g. metals) are harder than others (e.g. plastics, wood). Macroscopic hardness is generally characterized by strong intermolecular bonds, but the behavior of solid materials under force is complex; therefore, there are different measurements of hardness: "scratch hardness", "indentation hardness", and "rebound hardness". Hardness is dependent on ductility, elastic stiffness, plasticity, strain, strength, toughness, viscoelasticity, and viscosity. Common examples of hard matter are ceramics, concrete, certain metals, and superhard materials, which can be contrasted with soft matter. There are three
Janka Kulcsár the next year, she won a prize in the National Chamber Music Competition. Kulcsár works mainly with singers. She accompanied Marianna Sipos in the ARD International Music Competition in 2012. Founding member of the Moltopera Company since 2011. She accompanied among others Moltopera's production Don Giovanni, Magic Flute (in the Palace of Arts), Fledermaus, La Bohéme, Cavalleria Rusticana, Menotti's: The telephone, L'enfant et les sortiléges (in the National Theater of Pécs), and "How to survive an opera recital?" (in the Sziget Festival). Janka Kulcsár Janka Kulcsár (born 8 April 1985) is a Hungarian pianist and répétiteur, and a founding member