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US4011108A Expired / Lapsed US ⏱️ 0.0 years remaining

Cutting tools and a process for the manufacture of such tools

Assignee: Stora Enso Oyj
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Filing: 1976-01-19
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Granted: 1977-03-08
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Expires: 1996-01-19
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Abstract

Abstract The invention relates to a cutting tool containing 25-33 percent by weight of Co and certain amounts of W, Mo, C, B, Zr, Si, Mn, Cr, Ni and Fe containing normal contaminants, W + 2Mo being equal to 20-40 percent by weight, the structure of the tool consisting of a martensitic matrix having a grain size of 5-70 μm, determined as austenite grain size, containing 5-15 percent by volume of an intracrystalline, very homogeneously distributed fine-disperse phase consisting of an intermetallic compound of Fe, Co, W and/or Mo and, between the grains of the base mass, 20-30 percent by volume of a primarily precipitated phase mainly consisting of the same intermetallic compound but having a predominant grain size of 1-2 μm. The invention also relates to a process of preparing such a tool by finely dividing a melt of the composition given and cooling in a non-oxidizing atmosphere to a fine powder, hot-compacting the powder to an ingot, hot-working the ingot to a blank which is allowed to cool and is possibly soft annealed, forming the blank to a tool by reductive machining, solution annealing the tool by heating to the austenitizing temperature, cooling and tempering at least once.

Inventors

  • 👤 Per Ingvar Hellman
  • 👤 Bo Gunnar Klang

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 10:38
CPC Classifications
C; C22; C22C; C22C38/00; C22C38/10; B; B22; B22F; B22F3/00; B22F3/12; B22F3/16; C22C33/00; C22C33/02; C22C33/0257; C22C33/0278; C22C33/0285; Y; Y10; Y10S; Y10S148/00; Y10S148/902; Y10S148/905

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 192 words
Cutting tool containing ______________________________________ Co 25 - 33 percent by weight W 0 - 30 percent by weight Mo 0 - 20 percent by weight C 0 - 0.20 percent by weight Si 0 - 1.0 percent by weight Mn 0 - 0.4 percent by weight Cr 0 - 0.4 percent by weight Ni 0 - 0.4 percent by weight ______________________________________ and the balance Fe containing normal contaminants and where W + 2Mo being equal to 20 - 40% by weight, characterized by also containing 0.005 - 0.01% B or 0.005 - 0.03% by weight Zr or a mixture of both not exceeding 0.03% by weight, the structure of the tool consisting of a martensitic matrix having a grain size of 5 - 70 μ,m determined as austenite grain size, containing 5 - 15 percent by volume of an intracrystalline, very homogeneously distributed fine-disperse phase consisting of an intermetallic compound of Fe, Co, W and Mo and, between the grains of the base mass, 20 - 30 percent by volume of a primarily precipitated phase mainly consisting of the same intermetallic compound having a predominant grain size of 1 - 2 μ.m
Claim 2
Dependent Claim 192 words
Cutting tool containing ______________________________________ Co 25 - 33 percent by weight W 0 - 30 percent by weight Mo 0 - 20 percent by weight C 0 - 0.20 percent by weight Si 0 - 1.0 percent by weight Mn 0 - 0.4 percent by weight Cr 0 - 0.4 percent by weight Ni 0 - 0.4 percent by weight ______________________________________ and the balance Fe containing normal contaminants and where W + 2Mo being equal to 20 - 40% by weight, characterized by also containing 0.005 - 0.01% B or 0.005 - 0.03% by weight Zr or a mixture of both not exceeding 0.03% by weight, the structure of the tool consisting of a martensitic matrix having a grain size of 5 - 70 μ,m determined as austenite grain size, containing 5 - 15 percent by volume of an intracrystalline, very homogeneously distributed fine-disperse phase consisting of an intermetallic compound of Fe, Co, W and Mo and, between the grains of the base mass, 20 - 30 percent by volume of a primarily precipitated phase mainly consisting of the same intermetallic compound having a predominant grain size of 1 - 2 μ.m
Claim 3
Dependent Claim 123 words
A process of manufacturing a tool according to claim 1 comprising the steps: finely dividing a melt of the composition defined in claim 1 and cooling in a non-oxidizing atmosphere to a fine powder having a predominant grain size of 100 - 400 μm hot-compacting the powder by isostatic hot-pressing at 1200° - 1250° C to a billet, hot-working the billet at a temperature of 1000° - 1200° C to a blank which is allowed to cool, soft-annealing the blank at 875° - 910° C for 10 - 15 hours followed by cooling, forming the blank to a tool by reduction machining, solution annealing the tool by heating to an austenitizing temperature of 1200° - 1350° C cooling and tempering at least once.
Claim 4
Dependent Claim 33 words
A process according to claim 2, characterized by cooling the tool from the austenitizing temperature to 250° - 350° C and then tempering at 550° - 700° C for 2 - 5 hours.
Claim 5
Dependent Claim 35 words
A process according to claim 2, characterized by cooling the tool from the austenitizing temperature to room temperature, final working and tempering at 550° - 700° C for 2 - 5 hours at least once.

References Cited (Backward Citations)

US3746518A Cited
US3485620A Cited
US3649256A Cited
US3649257A Cited
US3655365A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-03-07 1980-09-06 1981-03-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-03-07 1984-09-06 1985-03-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-03-07 1988-09-06 1989-03-08 $7700.00 Window Closed / Lapsed

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