SU730473A1 - Method of manufacturing a made-up tool - Google Patents

Description

one

And the invention relates to powder metallurgy, in particular to methods for producing a composite tool. including diamond tools, and can be used when making the cutting tool out of. natural and synthetic diamonds, in the manufacture of drill bits, bits and grinding wheels.

A known method of manufacturing a prefabricated diamond tool, which involves forming an apoliferous matrix based on powdered material, a high strength, high hard element of the assembled tool, and combining it with metal tool cases by hot pressing under a pressure of 8–15 kbar 1.

The disadvantage of this method is that the laboriousness of the process when using the tool body with a developed system of protrusions and undercuts on the contact surface with the matrix, as well as exfoliation of the matrix at the place 25 of the connection with the body, is 20 seconds.

The closest in technical essence and the achieved effect is a method of manufacturing a cutting tool with carbide 30

cutting element, which involves forming a cutting high-strength and high-hard element from a solid alloy powder, fitting into the shape of a metal body, placing between the casing and the high-strength cutting element of an intermediate sealing layer of powder representing a mixture of refractory metals or carbides with relatively low-melting metals, and the subsequent mountains Pressing at 11001570 ° С 2.

The disadvantage of this method is that in the process of manufacturing a precast diamond tool, it is not possible to achieve high strength and reliability of the joint (diamond-bearing element with the body.

The purpose of the invention is to increase the strength and reliability of the connection of the assembled apmatic tool.

The goal is achieved by the fact that before placing the intermediate layer the contact surface of the housing is covered with electrolytic nickel or chromium, and a mixture of nickel or chromium powder with a powder of one of the compounds selected from the group boron carbide, chromium boride is used as the intermediate layer. The essence of the method is as follows. In the mold, diamond grains with a matrix powder or a diamond-containing mixture based on a refractory matrix powder, for example, from a mixture of powder, chromium, cobalt with carbide 1, am-titanium-k, chromium, and tungsten, are placed in a specific pattern. Powder mixture of the intermediate layer with a thickness after sintering of 0.1-1 mm is poured onto the uneven surface of the charge. The steel housing on the side of the contact surface is electrolytically coated with nickel or chrome. The housing is set to intermediate-. This layer conducts a cold prepressing and then hot pressing in a high pressure chamber at 850-1200 ° C and a pressure of 8-50 kbar. The electrolytic coating of nickel or chromium prevents the oxidation of the surface of the body, retains increased adhesive activity and provides the desired connection of the used solder layer with the steel casing. A strong connection of the diamond-bearing element with the tool body through the intermediate layer occurs in connection with the formation of boride nickel or chromium, in areas of close contact between boron carbide particles and chromium boride. Example 1. In a mold intended for pressing crowns of the type KSK-01-76, diamonds of the mark ASPK (30 pieces) are placed according to a given pattern. A matrix powder consisting of a mixture of 35 g of BK15 hard alloy and 70 g of carbonyl nickel is poured onto them. A powder mixture of the intermediate ‑ filler layer consisting of 16 g of Ni and 2 g of B4C is applied to the smoothed surface of the matrix powder. A steel crown with a flat end face is placed on the curing layer, on the contact surface of which a layer of O, O3-0, .05 mm is preliminarily applied electrolytically. The entire assembly is first cold pressed and then placed in a high pressure chamber and sintered under a pressure of 10 kbar at 900 ° C. Example 2. A diamond matrix matrix mixture consisting of a solid powder mixture is placed in a mold used for pressing crowns. BK15 alloy 50 g, carbonyl nickel 50 g and crushed diamonds brand ASPK with a grain size of 800-1600 microns in the amount of 15 carats. On the smooth-surface of the diamond-bearing mixture, an even layer of the powder mixture of the intermediate layer is placed on the packing layer consisting of 16 g Ni and 2 g CrBg. A crown case is installed on the top layer, on the contact surface of which 4 concentric grooves are preliminarily made and an electrolytic layer 0.03-0.05 mm thick is applied. The entire assembly is cold pressed, then placed in a high pressure chamber and sintered under a pressure of 15 kbar at 1050 ° C. Example 3. An annular layer of a diamond-bearing matrix charge, forming a high-strength element of a product consisting of a mixture of Tic and Ni powders with a weight ratio of 1: 4 and natural diamonds with a grain size of 200-400 microns with 100, is poured into a mold designed for pressing grinding wheels. % concentration. A mixture of an intermediate parasite layer consisting of Cr and in a ratio of 10: 1 by weight, in an amount ensuring its thickness after sintering of 0.3-0.5 mm, is placed on the smoothed surface of the diamond-bearing mixture. A steel body of a grinding wheel with a thickness of 05 mm previously deposited on the contacting surface is installed on the sealing layer. The assembly is cold pressed, after which it is placed in a high pressure chamber and sintered under a pressure of 8 kbarri 1200 C. Testing of drilling geological prospecting crowns and grinding discs for machining surfaces of marble and granite products made by this method showed their high performance and complete reliability fastening the diamond-bearing matrix to the steel case, including when operating on the most demanding modes. Thus, crowns with a diameter of 59 mm, reinforced with crushed diamonds in ASPK, are processed to complete wear without visible traces of matrix delamination with an axial load of 1000-1000 kg and a spindle speed of 30.00 rpm. At the same time, there are no traces of deterioration in the sintering process, which are characterized by relatively low heat resistance of ASPK diamonds. Formula of the invention The method of manufacture of the assembly tool, including placement between the metal case and the high strength element from the powder material of the intermediate powder layer from the powder and subsequent hot pressing, About tl and ch and y with the fact that, in order to increase the strength and reliability of the connection of the precast diamond tool, before placing the intermediate rlr contact its surface

57304736

electrolytically coated with nickel. Sources of information

or chromium, and a mixture of powder1 is used as intermediate taken into account in the examination of the layer. USSR author's certificate

nickel. or chromas powder of the single No. 532199, cl. B 22 F 3/14, 1976. from compounds selected from the group: 2. US patent No. 2999309, class 19 boron carbide, boride chromium, 194, 1961.

Claims (1)

Claim A method of manufacturing a prefabricated tool, comprising placing between the metal case and a high-strength element of a powdery material an intermediate solder layer of powder and subsequent hot pressing, with the aim of increasing the strength and reliability of the connection of a prefabricated diamond tool, before placing the intermediate layer, the contact surface of the case is electrolytically coated with nickel or chromium, and a mixture of nickel powder or chromium's is used as an intermediate layer. a powder of one of the compounds selected from the group: boron carbide, chromium boride.