Title:
SINTERED TOOL AND METHOD FOR PRODUCTION THEREOF
Document Type and Number:
WIPO Patent Application WO/2005/087418
Kind Code:
A1
Abstract:
A sintered tool, which has a surface layer portion containing boron B and/or silicon Si in an amount in a range of 0.010 to 2.0 wt %, wherein said surface layer portion contains hard particles such as WC in a content higher than that in the inner portion; and a method for producing the sintered tool which comprises compressing a mixed powder of the above hard particles and a binder metal such as Co to form a green compact having a desired shape, sintering the green compact, coating the surface of the resultant sintered compact with a boron and/or silicon applying agent, and subjecting the coated sintered compact to a heat treatment in vacuum wherein the coated compact is heated and kept within a temperature range which is lower than the solid phase temperature of the sintered compact and in which range a melt containing boron and/or silicon is formed in the sintered compact. In the above-mentioned heat treatment, boron and/or silicon in the boron and/or silicon coating layer is diffused into the surface layer portion, and a melt containing boron and/or silicon in the surface layer portion is diffused and moved into the inner portion, to thereby achieve the distribution density of hard particles in the surface layer portion of the sintered compact which is higher than that in the inner portion. The above sintered tool, wherein the above hard particles are bound via the above binder metal, exhibits the combination of an enhanced surface hardness and excellent toughness, which is achieved by the hardening without the growth of the hard particles.
Inventors:
IWASAKI MASAHIRO (JP)
YANAGITA HIDEFUMI (JP)
IKEBE MASAAKI (JP)
YANAGITA HIDEFUMI (JP)
IKEBE MASAAKI (JP)
Application Number:
PCT/JP2005/004351
Publication Date:
September 22, 2005
Filing Date:
March 11, 2005
Export Citation:
Assignee:
SANALLOY INDUSTRY CO LTD (JP)
IWASAKI MASAHIRO (JP)
YANAGITA HIDEFUMI (JP)
IKEBE MASAAKI (JP)
IWASAKI MASAHIRO (JP)
YANAGITA HIDEFUMI (JP)
IKEBE MASAAKI (JP)
International Classes:
B22F3/24; B23B27/14; B23B51/00; B23C5/16; B23P15/28; C22C29/08; C23C8/02; C23C10/02; C23C12/02; C23C26/02; C23C30/00; (IPC1-7): B23B27/14; B22F3/24; B23B51/00; B23C5/16; B23P15/28; C22C29/08
Foreign References:
| JPH04128330A | 1992-04-28 | |||
| JPH06157135A | 1994-06-03 | |||
| JPH04120274A | 1992-04-21 |
Attorney, Agent or Firm:
Kawamiya, Osamu (IMP Building 3-7, Shiromi 1-chome, Chuo-k, Osaka-shi Osaka 01, JP)
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