変圧器、積層、laminate, stack

Stacking factor, Wikipedia
The stacking factor（＊占積率）(also lamination factor or space factor[1]) is a measure used in electrical transformer design and some other electrical machines. It is the ratio of the effective cross-sectional area of the transformer core to the physical cross-sectional area of the transformer core. The two are different because of the way cores are constructed.

Transformer cores are usually made up of thin metal sheets stacked（＊積層）in layers. The layers are laminated（＊積層、ラミネート）with varnish or other insulating material. The purpose is to reduce eddy currents in the core, while keeping a high magnetic flux. Since the insulator is non-ferro-magnetic, little, if any, magnetic flux is contained within it. It is mainly in the metal sheets. The insulation takes up a finite space, so the effective area the flux occupies is less than the physical area of the core.[2]

The stacking factor is used when calculating the magnetic flux density within the core. Because the flux is confined within a smaller area in a laminated core, the flux density is higher than it would be in a homogeneous core.[3]

Laminated cores always have a stacking factor less than unity; a stacking factor of unity implies no laminate at all. Stacking factors are typically 0.95 or higher for transformer cores[4] and machine stators.[5] However, cores made from amorphous metal have a stacking factor of around 0.8, compared to 0.96 for silicon steel.[1]

複数のthin laminated coreをstackedしてcomplete iron core structureを作製する (Complete basics and theory of Electrical Transformer)

Stacked Transformer Lamination Core, Alibaba.Com　（積層コアのスタック、積み重ね）

laminationsをstackする

(Transformer Construction, ElectronicsTutorials)
Lamination stampingsをcore shapeにconnectしてlaminationsをstackすることによりコアを作製する。