Hi,
I see a all types of VIC cores, but never a list of used material. So please post your core material what you are using.
Personally I think the Initial permeability (μi) should be high. I never tested high μi. Look for Mn-Zn.
Soft ferrites
Ferrites that are used in transformer or electromagnetic cores contain nickel, zinc, and/or manganese compounds. They have a low coercivity and are called soft ferrites. The low coercivity means the material's magnetization can easily reverse direction without dissipating much energy (hysteresis losses), while the material's high resistivity prevents eddy currents in the core, another source of energy loss. Because of their comparatively low losses at high frequencies, they are extensively used in the cores of RF transformers and inductors in applications such as switched-mode power supplies (SMPS).
The most common soft ferrites are manganese-zinc (MnZn, with the formula MnaZn(1-a)Fe2O4) and nickel-zinc (NiZn, with the formula NiaZn(1-a)Fe2O4). NiZn ferrites exhibit higher resistivity than MnZn, and are therefore more suitable for frequencies above 1 MHz. MnZn have in comparison higher permeability and saturation induction.
http://www.bnf.com.hk/new_page_1.htmhttp://www.bnf.com.hk/new_page_3.htm Ferrite - Manganese Zinc (Mn-Zn)
My VIC core materials:
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Iron
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Plates (silicon alloy steel lamination)
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Ferrite - Nickel Zinc (Ni-Zn)
Material // μi // Bms(Gs) // Hc(Oe) // Br(Gs) // Tc(℃) // ρ(Ω-cm) // Frequency(MHz) // αur x 10-6/oC
A2G // 300 // 2800 // 0.52 // 1500 // 160 // 1*107 // 0.1~3 // 20~45
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400HH material 67 u=40 (Initial Permeability 40) B=2300 H=20 Br=800
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Br,
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