SU1502194A1 - Method of producing sintered bushes with a shoulder - Google Patents

Abstract

The invention relates to powder metallurgy, in particular, to methods for making sintered collar sleeves. The aim of the invention is to increase the productivity of the process while maintaining a high level of mechanical properties. To produce sleeves with a collar, the powder is poured into the matrix and pressed into a composite punch with a force of 6.5 kg with a back pressure of 1.9 kg to obtain a blank in the form of a glass. Then, the resulting billet is pressed to a sleeve with a collar with the same force and the same back pressure applied respectively to the outer and inner parts of the punch. After that, the blanks are sintered at 1150 ° C for 1.5 hours. The resulting bushings have the same mechanical properties as the bushings manufactured by a known method, but the performance of the method is 40% higher. 3 il.

Description

I

(21) 4183623 / 31-02 (22) 01/19/87 (46) 08/23/89. Bul And 3

(71) Communal Institute of Mining and Metallurgy

(72) M.T.Brezhnev, V.K.Butenko, N.M.Masl Kona and A.G. Grechikhin

(53) 621.762.4 (088.8)

(56) Patent of France 2015995, cl. B 60 B 17/00, 1970.

 USSR Author's Certificate No. 1163987, cl. B 22 F 3/02, 1983.

(54) METHOD OF MANUFACTURING SINTERED SLEEVE SLEEVES

(57) The invention relates to powder metallurgy, in particular to methods for making sintered collar sleeves. The aim of the invention is to improve performance.

method while maintaining a high level of mechanical properties. To make the sleeves with the collar, the powder is poured into the matrix and pressed with a composite punch with a force of 6.5 kg with a back pressure of 1.9 kg to obtain a blank in the form of a glass. Then, the resulting billet is pressed to a sleeve with a collar with the same force and the same back pressure, butt-BaehftMH-, respectively, to the outer and inner parts of the punch. After this, the blanks are sintered at 1150 ° C for 1.5 hours. The resulting bushings have the same mechanical properties as the bushings made by a known method, but the productivity of the method is higher. 3 ill., 1 tab.

(L

The invention relates to powder metallurgy, in particular, to methods for manufacturing parts of complex shape such as sleeve sleeves.

The aim of the invention is to increase the productivity of the process while maintaining a high level of mechanical properties.

Figure 1 shows the moment the powder lasts; Fig 2 is an assembly after primary pressing; FIG. 3 shows the assembly after re-pressing,

To manufacture a sleeve with a collar of iron powder of the type 1ChMHMZ, powder is poured into the matrix 1 along the axis of which the mandrel 2 is inserted, while the upper composite punch consisting of the outer 3, inner 4 and middle 5 parts is in the extreme position the lower punch 6 occupies the lowest position.

Then, a compound punch is moved from the drive, while a force equal to the pressing force (6.4 kg) is applied to the inner 4 and middle 5, and a force equal to the counter-pressure, which depends on the type of powder, is applied to the outer part 3. 0.2-0.5 pressing forces (in this case equal to 1.9 kg). When the pressing pressure from the powder side, equal to the counter-pressure force, is reached, parts 4 and 5 continue their downward movement, performing the njiouecc primary pressing of the powder by squeezing back

about

four

31502

This means that part 3 of the punch under the action of the pressure on the side of the displaced powder moves upwards, acting on the powder with a force equal to the back pressure.

After the completion of the primary pressing process, a blank is obtained in the shape of a cup (Fig 2).

Then a force equal to the force of the back pressure is applied to the inner part 4 of the punch.,; And a force equal to the force of compaction (6.5 kg) is applied to the outer part 3, while the middle part 5 remains fixed , The re-pressing period begins. Under the action of a pressing force acting on the part of the punch part 3, the powder forming the walls of the glass is pressed into the ring post formed by the mandrel 2 and the inner wall of the part 5, while part A departs with a constant force equal to the back pressure, and part 3 is lowered until its end coincides with the end of the middle part 5. This leads to the fact that during the re-pressing process, the walls of the glass are inverted and the last one turns into a sleeve with a collar, and the surface of the glass turns into about the inner surface of the sleeve, and the inner surface of the glass - into the outer surface of the sleeve.

After the re-pressing process has been completed, parts 3, 5 and then part A are retracted to the extreme upper position. Then, the pressed product is removed from the mold die by the lower punch 6, after which the punch 6 is returned to its original position, and the pressing cycle is repeated. Extraction of the workpiece is subjected to sintering of the rto regime: 1150 C for 1.5 h in dissociated ammonia.

Famous

Proposed

5 0 0. 5

40 45

five

The table shows the results of testing the mechanical properties of products manufactured using double pressing and subsequent sintering in comparison with the mechanical properties of products manufactured by a known method, including pressing, sintering, repeated pressing and final sintering.

As can be seen from the table, the mechanical properties of products manufactured by both methods have the same high level of mechanical properties, but the proposed method allows to exclude one sintering operation, which approximately 4% improves the performance of the method.

Claims (1)

Invention Formula A method of manufacturing sintered sleeves with a collar, which includes loading the powder into the matrix, primary pressing with a punch, re-pressing with a back pressure of 0.2-0.5 pressing force and subsequent sintering, characterized in that The level of mechanical properties of the extrusion is carried out by a composite punch with external, intermediate and internal parts; primary pressing is obtained by applying pressure to the internal and intermediate parts of the plastic to obtain a blank in the form of a glass, and repeated pressing is carried out by applying pressure to the outer part of the punch and counter pressure to the inner part with the stationary intermediate part before flowing the powder into the cavity formed by the inner part of the punch. Gostavitel V.Eremenko Editor I.Gorn Tehred L.OliGshyk Order 5006/14 Circulation 711 VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab., D / 5 IgdsAie i / e.J Corrector S.Cherni Subscription