SU1072501A1 - Refractory nickel-base alloy - Google Patents

Abstract

HEAT-RESISTANT ALLOY BASED; Nickel containing carbon, chromium,;

Description

The invention relates to metallurgy, in particular to the field of nickel-based superalloys, and can be used in the construction of gas, turbine engines operating before | . ,:

In the design of gas turbine engines there are a number of parts operating under conditions of multiple heat cycles and sudden temperature drops, which inevitably lead to deformation.

Lack of material with a sufficient supply of plasticity can lead to premature failure.

Therefore, highly elastic non-aging alloys, which are a solid solution that does not contain reinforcing phases, are used for such parts. The most heat resistant alloys

This type is an EI868 alloy containing 24.5% chromium and 14.5% tungsten. Alloy AY 868 has a 100 hour

-sJl strength at 800 ° C - 11 kg / mm, and

N9 at 900 ° C - 5.2 kg / mm.

The closest in technical essence is a heat-resistant nickel-based alloy containing, in wt.%:

sixteen

Chromium

Cobalt

thirty

Tungsten

20

up to 0.1

Carbon Else

Nickel

Known material has not sufficiently high characteristics of heat resistance, technological plasticity and thermal fatigue. The aim of the invention is to increase heat resistance, process plasticity and heat fatigue. To achieve the goal, the heat-resistant alloy containing carbon, chromium, cobalt and tungsten, additionally contains aluminum and an element selected from the group of lanthanum, neodymium, with the following ratio of components, wt.%: 0.02-0.1 Carbon Chromium Cobalt Tungsten 0.2-0.7 Aluminum Element selected from the group of 0.01-0.1 neodymium lanthanum Else Nickel In the proposed alloy, cobalt and tungsten harden the solid solution at high temperatures. - Chromium also hardens the solid solution, but at the same time this element increases the oxidation resistance. The introduction of small additions of rare-earth elements neodymium or lanthanum contributes to an even greater increase in oxidation resistance. Several heats of the proposed composition were melted (Table 1). The melting was carried out in a vacuum induction furnace with a capacity of 50 kg with an ingot size of 16-17 kg. The ingots were forged on boulders that rolled on a 1.5 mm thick sheet. Sheet blanks were subjected to heat treatment, which consisted of heating at a temperature of 8–10 min with subsequent cooling in air. Tests for thermal fatigue osu; was implemented as follows. . A sample in the form of a plate width; 20 mm and a length of 185 mm has a notch at the end with a radius of 0.1 mm. The notched end automatically undergoes alternate heating to a predetermined temperature and is cooled in water until a crack appears from a notch 0.5 mm long. The criterion of thermal fatigue was the number of heating - cooling cycles until a crack of the specified length appears. .: Compared alloys, having in its composition of neodymium or lanthanum with reproduced Ponskoy alloy. Tests were conducted on a thermal cycle of 20-900-20 C. The results of the tests are presented in Table 2. Table 2 presents the test results for thermal fatigue and shows the following properties: heat resistance, heat resistance and impact viscosity. As i can see from this table, the proposed alloy by its complex of properties exceeds the known one, namely by heat resistance fatigue by 40-50%, by heat resistance 2 times, in impact strength more than 1.6 times at a temperature of 1000-P50s. Thus, the proposed alloy according to the complex of properties makes it possible to increase the reliability and resource of products of new and prospective GTE more than 1.5 times. Table 1

table 2

89

3.5

151,115

280 3.5 E86 4.0

54 104 4.0

50

92 3.5

156

95 4.0

52

56

290

3.5 d

20 26 18 23 28 25

24 26 20 25 24 24

13 15 G2 14 18 16

29 33 28 31 30 31

14

sixteen

 7

ten

Claims (2)

А NICKEL-RESISTANT HEAT RESISTANT ALLOY containing carbon, chromium, 0.02-0.1 20-25 25-32 10-16 0.2-0.7 2 cobalt and tungsten; In addition to heat resistance, technological plasticity and thermal fatigue, it additionally contains aluminum and an element selected from the lanthanum group, neodymium in the following ratio of components, wt.%: Carbon Chrome Cobalt Tungsten Aluminum Element selected from the lanthanum group, neodymium. Nickel ω 0.01-0.1 Rest