Hardness a fixed height onto a material. This type of hardness is related to elasticity. The device used to take this measurement is known as a scleroscope. Two scales that measures rebound hardness are the Leeb rebound hardness test and Bennett hardness scale. There are five hardening processes: Hall-Petch strengthening, work hardening, solid solution strengthening, precipitation hardening, and martensitic transformation. In solid mechanics, solids generally have three responses to force, depending on the amount of force and the type of material: Strength is a measure of the extent of a material's elastic range, or elastic and plastic ranges together. This is
Carbonate hardness [milli[equivalent]s] per litre (meq/L) or ppm. Carbonate hardness expressed in ppm does not necessarily equal carbonate alkalinity expressed in ppm. formula_1 whereas formula_2 However, for water with a pH below 8.5, the CO will be less than 1% of the HCO so carbonate alkalinity will equal carbonate hardness to within an error of less than 1%. In a solution where only CO affects the pH, carbonate hardness can be used to calculate the concentration of dissolved CO in the solution with the formula CO = 3 × KH × 10, where KH is degrees of carbonate hardness and CO is