Research on Errors in Situ of Magnetic Measurement in High Hydrostatic Pressure Vessel－(1) The Influence of Leakage Flux

In order to research the influence of leakage flux in high hydrostatic pressure vessel, we have measured the magnetization curve under five different ambient conditions, then compared the B-H curve measured on table far from iron with B-H curve measured in situ in pressure vessel. Finally we calculated the relative errors, c0/c0, produced by leakage flux of electric solenoid with 13 layers in pressure vessel. The results show that (1) for empty secondary coil, c0/c0=-1.90%～-1.27% (400 Hz), -0.36%～-0.64% (1 000 Hz); (2) for Fe nanometer-scale powder, magnetization curve and initial B-H curve are all straight lines, i.e. both of them possess constant magnetic permeability, . Relative errors produced by leakage flux in high pressure vessel, /=3.9%～3.8%, about one time higher than that of (1).