A rectangular parallelepiped ingot defined by a height H, a width W and a length L, having longitudinal faces extending between two end faces, having a volume between 0.15 m3 and 0.80 m3 and a surface area to volume ratio between 10 m−1 and 18 m−1, made of at least one metal, including at least one notch and a notch tip along the ingot length, wherein the at least one notch is configured such that: MaxD