Claims
- 1. A composite magnetic member made from steel material, comprising:a hollow ferromagnetic steel material portion; and a hollow non-magnetic steel material portion continuously formed to said ferromagnetic steel material, wherein said non-magnetic steel material has a residual compressive stress to prevent stress corrosion cracks.
- 2. A composite magnetic member according to claim 1, wherein the steel material is comprised of C of not more than 0.6 weight %, Cr of 12 to 19 weight %, Ni of 6 to 12 weight %, Mn of not more than 2 weight %, and a residual portion composed of Fe and inevitable impurities.
- 3. A composite magnetic member according to claim 1, wherein Hirayama's equivalent Heq=[Ni%]+1.05[Mn%1]+0.65[Cr%]+0.35[Si%]+12.6[C%]is 20 to 23%, nickel, equivalent Nieq=[Ni%]+30[C%]+0.5[Mn%] is 9 to 12%, and chromium equivalent Creq=[Cr%]+[Mo%]+1.5[Si%]+0.5[Nb%] is 16 to 19%.
- 4. A composite magnetic member according to claim 1, wherein the cross-section thereof is a U-shape.
- 5. A composite magnetic member according to claim 4, wherein said ferromagnetic steel material portion is located on a side of a bottom portion of said U-shape and said non-magenta steel material portion is located on a side of an opening end portion thereof.
- 6. A composite magnetic member according to claim 1, wherein said composite magnetic member is configured for use as a sleeve in an electromagnetic valve which has a coil, a plunger slidably arranged in said sleeve, and a stator arranged being opposed to said plunger with a space therebetween, wherein a fluid passage is selectively opened and closed which said plunger is moved by excitation of said coil and said non-magnetic steel material portion of said composite magnetic member is arranged so that said non-magnetic steel material portion surrounds said space formed between said plunger and said stator.
- 7. composite magnetic member made from steel material, comprising:a hollow ferromagnetic steel material portion; and a hollow non-magnetic steel material portion continuously formed to said ferromagnetic steel material, wherein a boundary portion between said ferromagnetic steel material portion and said non-magnetic steel material has a residual compressive stress to prevent stress corrosion cracks.
- 8. A composite magnetic member according to claim 7, wherein the steel material is comprised of C of not more than 0.6 weight %, Cr of 12 to 19 weight %, Ni of 6 to 12 weight %, Mn of not more than 2 weight %, and a residual portion composed of Fe and inevitable impurities.
- 9. A composite magnetic member according to claim 7, wherein Hirayama's equivalent Heq=[Ni%]+1.05[Mn%]+0.65[Cr%]+0.35[Si%]+12.6[C%] is 20 to 23% nickel equivalent Nieq=[Ni%]+30[C%]+0.5[Mn%] is 9 to 12%, and chromium equivalent Creq=[Cr%]+[Mo%]+1.5[Si%]+0.5[Nb%] is 16 to 19%.
- 10. A composite magnetic member according to claim 7, wherein the cross-section thereof is a U-shape.
- 11. A composite magnetic member according to claim 10, wherein said ferromagnetic steel material portion is located on a side of a bottom potion of said U-shape and said non-magnetic steel material portion is located on a side of an opening end portion thereof.
- 12. A composite magnetic member according to claim 7, wherein said composite magnetic member is configured for use as a sleeve in an electromagnetic valve which has a coil, a plunger slidably arranged in said sleeve, and a stator arranged being opposed to said plunger with a space therebetween, wherein a fluid passage is selectively opened and closed when said plunger is moved by excitation of said coil, and said non-magnetic steel material portion of said composite magnetic member is arranged so that said non-magnetic steel material portion surrounds said space formed between said plunger and said stator.
Priority Claims (5)
Number |
Date |
Country |
Kind |
8-131428 |
Apr 1996 |
JP |
|
8-280064 |
Sep 1996 |
JP |
|
9-17445 |
Jan 1997 |
JP |
|
9-23292 |
Jan 1997 |
JP |
|
9-47247 |
Feb 1997 |
JP |
|
Parent Case Info
This is a division of Application No. 08/844,341, filed Apr. 18, 1997 now U.S. Pat. No. 6,143,094.
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A |
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A |
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Non-Patent Literature Citations (1)
Entry |
“The Proceedings of the 1996 Japanese Spring Conference for the Technology of Plasticity”, pp. 4, 40-41. |