The modern theory of ferromagnetic magnetization processes has from the
beginning recognized the importance of magnetoelastic inter- actions.
Most of the magnetoelastic calculations, however, have been basecl on
the theory developed by R. BECKER and others in the early 1930's. That
theory has several defects; how to remedy them is the subject of this
monograph. I first became aware of the shortcomings of the traditional
theory thru a critical study of electric and magnetic forces, which I
undcrtook as a member of the COULOMB'S Law Committee of the American
Asso- ciation of Physics Teachers. My conclusions were published in 1951
in the American 10Z/rnal of Physics; an application of them to a problem
in magnetostriction was published in 1953 in Reviews oflvlodern Physics.
With the development, in 1956, of the "nucleation field" theory of
micromagnetics, the need for a systematic and self-consistent theory of
magnetoelastic interactions became more pressing. The traditional theory
predicted that the nucleation field should differ negligibly from that
of a rigid body; but my 1953 magnetostriction calculation suggested that
terms omitted in that theory might be important. In the academic year
1963/64, 1 was finally able - thanks to a sabbatical furlough - to find
the time needed for systematic development of a basic theory of
magnetoelastic interactions in a ferromagnet.