摘要 |
A metallic member including not more than 0.6% C, 12 to 19% Cr, 6 to 12% Ni, not more than 2% Mn, not more than 2% Mo, not more than 1% Nb and the balance being Fe and inevitable impurities, whereHirayama's equivalent H eq=[Ni %]+1.05 [Mn %]+0.65 [Cr %]+0.35 [Si %]+12.6 [C %] is 20 to 23%;Nickel equivalent Ni eq=[Ni %]+30 [C %]+0.5 [Mn %] is 9 to 12%, andChromium equivalent Cr eq=[Cr %]+[Mo %]+1.5 [Si %]+0.5 [Nb %] is 16 to 19, wherein % is by weight, is made to have at least one ferromagnetized part having a magnetic flux density B4000 of not less than 0.3 T and at least one non-magnetized part having a relative magnetic permeability mu of not more than 1.2 at a temperature of not less than -40° C., as continuously and integrally formed. The non-magnetized part has crystal grain sizes of not more than 30 mum. The metallic member is subjected to magnetization and successive local non-magnetization of part or parts of the ferromagnetized member, and the thus obtained composite magnetic member is employed as a support member such as a sleeve in electromagnetic valves.
|