Method and composition for producing hard surface carbide insert tools
OwnerWilliam J. Brady, Harlan U. Andersoninventors
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Abstract
A hard surfaced heavy duty cutting tool having an abrasive insert and method for hard surfacing and bonding metallic materials. The composition used in hard surfacing comprises a slurry coating including a high nickel, metal alloy powder and a fluxing agent. The slurry composition is fused at temperatures of about 1830.degree.-1925.degree. F. to bond an abrasive cutting element, such as tungsten carbide in a base metal matrix, to a cutting tool to form the primary working element thereof. The slurry composition is also fused at the same temperature range to form a wear surface of the tool adjacent to the abrasive insert as a hard surface, wear resistant coating in which abrasive compounds and other materials may be incorporated.
Claims40
A heavy duty cutting tool of the type subjected to large impact forces in performing such cutting functions as trenching, boring, drilling, sawing, plowing, crushing and the like as in industrial mining and like operations, said cutting tool including a tempered steel body and having primary cutting means thereon and a wear surface extending away from said primary cutting means, and a hard surface coating applied to said primary cutting means and said wear surface, said hard surface coating comprising a metal alloy composition having a high nickel content in the range of 45-75 weight percent and a substantial amount in the range of 5-25 weight percent of a glass-forming fluxing agent, and said coating being fused to said tool body at a temperature in the range of 1830.degree.-1925.degree. F. with a resultant hardness in the range of 55-68 Rockwell C.
A heavy duty cutting tool of the type subjected to large impact forces in performing such cutting functions as trenching, boring, drilling, sawing, plowing, crushing and the like as in industrial mining and like operations, said cutting tool having a tempered ferrous metal base with a support surface thereon and a wear surface adjacent to said support surface, an abrasive cutting element bonded to said support surface by a bonding material and projecting from said cutting tool base to form a primary cutting tip, and a hard surface coating fused onto said wear surface adjacent to said primary cutting tip, one of said bonding material and hard surface coating being comprised of a metal alloy composition having a high nickel content in the range of 45-75 weight percent of the composition and a substantial amount in the range of 5-25 weight percent of a glass-forming fluxing agent and being fused at temperatures in the range of 1830.degree.-1925.degree. F., and said hard surface coating having a resultant hardness in the range of 55-68 Rockwell C when fused to the wear surface of said metal base.
A heavy duty cutting tool of the type subjected to large impact forces in performing such cutting functions as trenching, boring, drilling, sawing, plowing, crushing and the like as in industrial mining and like operations, said cutting tool comprising a tempered ferrous metal base provided with a support surface and a wear surface adjacent thereto, an abrasive cutting element having a base and said support surface and cutting element base having complementary surfaces for seating engagement, at least one of said complementary surfaces and wear surface being provided with a metal alloy fusing composition comprising 16-19 weight percent chromium, 3-6 percent iron, 0.5-2 percent carbon, 3-4 percent boron, 3-5 percent silicon, and 45-75 percent nickel, said composition being fused at a temperature in the range of 1830.degree.-1925.degree. F. and tempered to a hardness in the range of 45 to 68 Rockwell C.
A method for making a heavy duty, ferrous metal cutting tool having a support surface complementary to a base surface of an abrasive cutting element to be bonded to the support surface and having a wear surface adjacent to said support surface, said method comprising the steps of forming a metal alloy slurry having a composition comprised of a metal alloy powder with about 16-19 weight percent of chromium, 3-6 percent iron, 0.5-2 percent carbon, 3-4 percent boron, 3-5 percent silicon and 45-75 percent nickel, a glass-forming fluxing agent selected from a group composed of boron compounds, silicon compounds, boro-silicates and fluoro-boro-silicates and in an amount to provide 5 to 25 percent by weight of said alloy powder, and a liquid vehicle sufficient to form a flowable slurry;
- applying said metal alloy slurry in the form of a coating to at least one of the wear surface, support surface and base surface;
- drying said coating and fusing said coating to the applied surface at a preselected temperature in the range of 1830.degree.-1925.degree. F. to provide at least one of a hard surface coating on the wear surface and a bond between said cutting element and said support surface of said tool.
A method for making a heavy duty cutting tool having a tool body formed of tempered steel at a hardness of about 43-52 Rockwell C and an abrasive cutting element formed of tungsten carbide in a base metal matrix at a hardness of about 80-90 Rockwell C, said carbide cutting element to form the primary cutting element of said tool and said tool body having a support surface to receive a complementary surface of said carbide element and a wear surface on said tool body extending away from said support surface thereof;
- said method comprising forming a metal alloy slurry comprising a metal alloy powder composition of about 16-19 weight percent of chromium, 3-6 percent iron, 0.5-2 percent carbon, 3-4 percent boron, 3-5 percent silicon and 45-75 percent nickel, a glass-forming fluxing agent selected from a group composed of boron compounds, boro-silicates and fluoro-boro-silicates, silicon compounds, and in an amount to provide 2.5 to 25 percent by weight of said alloy powder composition, and a liquid vehicle in an amount of about 2 to 15 percent sufficient to form a flowable slurry;
- applying a brazing compound to at least one of support surface and complementary surface and assemblying said carbide element on said support surface;
- applying said metal alloy slurry to said wear surface of said tool body to form an exterior surface coating thereon;
- drying said slurry coating;
- and heating said assembled tool body and carbide element throughout the zone of said coating to fusion temperatures in the range of about 1830.degree.-1925.degree. F. to braze the complementary surface of said carbide element to the support surface of said tool body and to fuse said exterior surface coating to said wear surface of said tool body to form a wear coating having a hardness greater than that of the tool body and in the range of 45-68 Rockwell C.
Dependencies are inferred from the claim text.