Driving by the rising raw material cost of Samarium Cobalt magnets, permanent magnets based on the Nd2Fe14B intermetallic phase were discovered independently and almost simultaneously by Dr. John Croat from General Motors and Dr. Masato Sagawa from Sumitomo Special Metal late in 1982. The route to the discovery of this new member of permanent magnets family was totally different for the two companies. General Motors discovery was an outgrowth of attempts to produce metastable intermetallic compounds from rapidly solidified rare earth-iron materials while Sumitomo discovery resulted from the search for ternary R-Fe-X intermetallic compounds using the available powder metallurgy process used to produce Samarium Cobalt magnets. After a period of time during which patents were filed, both companies announced their discoveries at the 29th MMM conference held in Pittsburgh, PA in November 1983. Because neither company could sell magnets on a worldwide basis, an agreement was finally reached between the two companies that Sumitomo obtained the rights to sell Neodymium magnets with grain size > 1 μm and General Motors owned the right to sell Neodymium magnets with grain size < 1 μm.
