MULTILAYERED SHEET OF ELECTRICAL STEEL Russian patent published in 2021 - IPC C22C38/02 C22C38/60 C21D8/12 H01F1/147 H01F1/16 

FIELD: metallurgy.

SUBSTANCE: invention relates to the field of metallurgy, namely to a multilayer sheet of electrical steel used as a material for the manufacture of engine cores for hybrid electric vehicles. The sheet contains an inner layer and surface layers located on both sides of the inner layer. Each of the surface layers has a chemical composition containing, wt%: Si: 2.5-6.0 and at least one element selected from the group consisting of P: 0.01-0.1, Sn: 0.001- 0.1 and Sb: 0.001-0.1, the rest is Fe and inevitable impurities. The inner layer has a chemical composition containing, wt%: Si: 1.5-5.0 and at least one element selected from the group consisting of P: 0.01-0.1, Sn: 0.001-0, 1 and Sb: 0.001-0.1, the rest is Fe and inevitable impurities. The sheet has a difference ΔSi between the Si content in each of the surface layers, [Si]₁, and the Si content in the inner layer [Si]₀, in the form of [Si]₁ - [Si]₀, amounting to 0.5-4.0 wt. %, the difference ΔAl between the Al content present as an inevitable impurity in each of the surface layers [Al]₁ and the Al content present as an inevitable impurity in the inner layer [Al]₀ in the form | [Al]₁- [ Al]₀ | constituting 0.05 mass% or less; the ratio of the total thickness of the surface layers t₁ to the thickness of the multilayer electrical steel sheet t, in the form of t₁ / t, equal to 0.10-0.70, the magnetic flux density B₁₀ at a magnetic field strength of 1000 A / m of 1.3 T or more, the ratio B₁ / B₁₀ of the magnetic flux density of B₁ at a magnetic field strength of 100 A / m to B₁₀ of 0.45 or more, and the iron loss W1₁₀ / _1k in W / kg at a frequency of 1 kHz and the highest magnetic flux density of 1.0 T and sheet thickness t in mm satisfy the relationship: W_10/1k ≤ 15 + 140 × t (1).

EFFECT: sheet has low high frequency iron loss and high magnetic flux density.

2 cl, 5 dwg, 2 tbl