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 Bryl National Academy of Sciences of Belarus. Bryl's first story appeared in 1938 and his first short story collection appeared in 1946. The first collection of stories was called "Apaviadanni" (Stories). Bryl's books are mostly works of psychological fiction and his characters tend to be sensitive and prone to introspection. They were largely set in Belarusian villages and frequently about the people's fight against the Nazis. Janka Bryl Janka (Yanka) Bryl (, August 4, 1917 – July 25, 2006) was a Belarusian writer best known for his short stories. He was one of the older generation of Soviet writers who had