Maximum energy product

In magnetics, the maximum energy product is an important figure-of-merit for the strength of a permanent magnet material. It is often denoted (BH)max and is typically given in units of either kJ/m3 (kilojoules per cubic meter, in SI electromagnetism) or MGOe (mega-gauss-oersted, in gaussian electromagnetism). 1 MGOe is equivalent to 7.958 kJ/m3.

During the 20th century, the maximum energy product of commercially available magnetic materials rose from around 1 MGOe (e.g. in KS Steel) to over 50 MGOe (in neodymium magnets). Other important permanent magnet properties include the remanence (Br) and coercivity (Hc); these quantities are also determined from the saturation loop and are related to the maximum energy product, though not directly.