SU1570864A1 - Method of resistance-reactive soldering of refractory nickel alloys - Google Patents

Abstract

The invention relates to soldering, in particular, to methods of contact-reactive soldering of dispersion-hardening and dispersion-strengthened nickel alloys, and can be used in power engineering. The purpose of the invention is to increase the long-term plasticity of paired compounds by preventing the formation of brittle intermetallic phases. Between the joining surfaces of parts made of heat-resistant nickel alloys, an intermediate layer of vanadium melt with 6.0-10.0 wt.% Of tungsten is placed, heated to the temperature of formation of the liquid phase and a compressive force is applied. The introduction of a specified amount of tungsten into vanadium ensures the formation of a melt without intermetallic compounds. When compressed, almost the entire liquid phase is squeezed out, and the compound becomes almost uniform. The long plasticity of the paired compounds obtained through a tungsten alloy with 6.0–10.0 wt.% Tungsten is higher than in compounds obtained through pure vanadium.

Description

(21) 4409424 / 31-27

(22) 04.13.88

(46) 06/15/90. Bul No. 22

(72) V. F Kvasnitsky, V. M. Zabolotsky,

A. M. Kostin, S. G. Kulik,

S.M. Samokhin and N.P. Zhitnikov

(53) 621.791.36 (088.8)

(56) Welding journal. 1970, No. 9, p. 395-409.

(54) METHOD OF CONTACT-REACTIVE EHEAD OF NICKEL-HEATED HEATING ALLOYS

(57) The invention relates to soldering, in particular to methods of contact-reactive soldering of dispersion-hardening and dispersion-strengthened nickel alloys, and can be used in power engineering. The purpose of the invention is to increase

prolonged plasticity of solder joints by preventing the formation of fragile intermetallic phases. Between the joining surfaces of parts made of heat-resistant nickel alloys, an intermediate layer of Vanadium alloy with 6.0-10.0 wt.% Of tungsten is placed, heated to the temperature of formation of the liquid phase and a compressive force is applied. The introduction of a specified amount of tungsten into vanadium ensures the formation of a melt without intermetallic compounds. When compressed, almost the entire liquid phase is squeezed out, and the compound becomes almost uniform. The long ductility of compounds obtained through a tungsten alloy with 6.0–10.0 wt.% Tungsten is higher than in compounds obtained through pure vanadium.

SB

The invention relates to soldering, in particular, to methods of contact-reactive soldering of dispersion-hardening and dispersion-strengthened nickel alloys used in the field of power engineering in assemblies and structures operating for a long time at high temperatures.

The purpose of the invention is to increase the long-term plasticity of paired compounds by preventing the formation of brittle intermetallic phases.

The method is implemented as follows.

Between the joining surfaces of parts made of heat-resistant nickel alloys, an intermediate layer of Vanadium alloy with 6.0-10.0 wt.% Of tungsten is placed, heated to the temperature of formation of the liquid phase and a compressive force is applied.

Use as an intermediate layer of vanadium alloy from 6.0 to 10.0 wt.%

In the process of soldering, tungsten provides for the formation of a single eutectic of nickel-vanadium enriched in tungsten with a wide range of dissolution without the cr phase, which ensures a high plasticity of the joint. Almost all the liquid from the soldered joint is squeezed out. High bond strength is provided by a solid solution hardening mechanism.

Using the proposed method provides increased service life of various units, in particular gas turbine engines.

Example. Samples of the foundry alloy of the left-hand alloy EP539MMU fell through gaskets (P) of the following composition, wt.%: P1 92V - 8W; P2 94U-6W; PZ 90V - 10W; A4 95V -5W; П5 89V - 11W; P6 100V (prototype).

The pads were made in the form of foil by rolling. The soldering was carried out according to the mode: soldering temperature 1215 ° С, holding for 5 min.

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application to the details of the force of compression of 10 MPa.

Mechanical tests of paired samples for long-term ductility showed that when soldering through a P1 gasket, the best results are achieved, the nucleation of the CRASHING occurs at 6 ° C

910 MPa; however, the time to failure is on average 10 hours with

 5.1% A few decrease in results when soldering through P2 and PZ gaskets. At the same time, 6,24,4,4,6%, 880 MPa; , 5 hours. These indicators are quite good, while the deviation from the best performance with gasket III does not generally exceed 10%, which makes it advisable to use these alloys as a gasket for contact-reactive brazing of nickel-based alloys .

With an increase in the concentration of tungsten in the alloy, for example, an P5 gasket, a noticeable decrease in the long-term ductility of the soldered compounds is observed. On average, the results are reduced by more than 30% compared with the P1 gasket. At the same time, 9%, MPa, .3 h.

A further increase in the concentration of tungsten in the alloy does not make sense, since the contact melting temperature begins to increase, which is unacceptable due to the loss of properties of the base metal during brazing.

A decrease in the concentration of tungsten in the alloy to 5% (P4) leads to a negative effect. The bp, and tp are significantly reduced by an average of 30-40%.

Analysis of the test results shows that the use of a vanadium alloy with 6.0-10.0 wt.% W as a gasket provides an increase in long-term ductility compared to the prototype (gasket P6) on average 2 times.

Claims (1)

Invention Formula A method of contact-reactive soldering of heat-resistant nickel alloys, in which an intermediate layer of material that enters into contact melting with nickel is placed between the surfaces to be connected, is heated to the temperature of formation in the contact of the liquid phase and a compression force is applied, characterized in that In order to increase the long-term ductility of soldered compounds by preventing the formation of brittle intermetallic phases, vanadium alloy is taken as the material entering into contact melting with nickel , 0-10.0 wt.% Tungsten.