The apparent mobility of a recrystallization front with variable mobility

When the mobility of a recrystallization front is varying periodically along the front and a uniform pressure P is acting on it and the specific front energy, γ , is constant, the front will, after a transient move forward with a stationary shape and a constant apparent velocity in a direction perpendicular to the direction in which the mobility is varying. The corresponding apparent mobility M app was determined in a semi-analytic way. When the width of the variation in mobility is small compared to the length λ = γ / P , M app is given by the simple expression 1/ M app =〈1/ M 〉. With increasing values of λ the front becomes increasingly wavy, provided the variation in mobility is not too small, and M app approaches a constant value independent of the variation in mobility.