RU2356978C2 - Alloy on basis of titanium and product, implemented of it - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: invention relates to non-ferrous metallurgy, particularly to creation of titanium alloys. It can be used for manufacturing of details and units of aerospace and rocket engineering, material of which operates in conditions of warm temperatures. Alloy on the basis of titanium contains, wt %: aluminium 3.0-7.0, molybdenum 1.5-3.0, chrome 0.8-2.3, iron 0.2-0.7, zirconium 0.001-0.095, tungsten 0.001-0.095, silicon 0.16-0.6, oxygen 0.03-0.2, titanium - the rest.

EFFECT: receiving of alloy with high durability and long-term strength at high temperature and high endurance, that provides reduction of details weight and units and to increase structural behavior resource.

2 cl, 2 tbl, 1 ex

Description

The invention relates to the creation of titanium alloys intended for the manufacture of brackets, panels, power elements of nose fairings and other details, the material of which operates at high temperatures in aviation, space and rocket technology, as well as non-ferrous metallurgy.

Known alloy based on titanium having a chemical composition, wt.%:

aluminum 5.5-6.75 vanadium 3.5-4.5 iron 0.25-0.35 carbon 0.10-0.30 oxygen 0.15-0.25 nitrogen 0.05-0.14 titanium rest

(U.S. Patent No. 5,759,484).

The alloy can be used for the manufacture of power structural elements, such as brackets, beams and other parts and components of aerospace engineering.

The disadvantages of the alloy are low performance when working in high temperatures.

The disadvantage of the products is the low operational reliability. Known alloy based on titanium having a chemical composition, wt.%:

aluminum 2.0-6.8 molybdenum 0.5-3.8 vanadium 2.0-9.0 chromium 0.4-1.6 iron 0.2-1.2 zirconium 0.02-0.3 oxygen 0.04-0.14 carbon 0.02-0.09 hydrogen 0.003-0.014 nitrogen 0.008-0.04 silicon 0.04-0.14 titanium rest

(RF patent No. 1131234).

Structures of aerospace and rocket technology (such as engine mounts) are made of alloy.

The disadvantages of the alloy and its products are reduced characteristics of short-term and long-term strength at high temperatures.

Also known is an alloy based on titanium of the following chemical composition, wt.%:

aluminum 4.3-6.0 molybdenum 4.0-5.6 vanadium 4.0-5.6 chromium 0.5-1.5 iron 0.5-1.5 zirconium 0.03-0.5 oxygen 0.02-0.2 carbon 0.01-0.2 hydrogen 0.003-0.03 nitrogen 0.01-0.05 copper 0.003-0.15 nickel 0.003-0.15 titanium rest

(RF patent No. 2082802).

Parts and components of aerospace and rocket technology are made from this alloy.

The disadvantages of the alloy and its products are reduced strength characteristics at high temperature and low endurance.

The closest analogue taken as a prototype is an alloy based on titanium of the following chemical composition, wt.%:

aluminum 4.0-6.5 molybdenum 1.5-2.5 vanadium 4.0-5.0 chromium 0.8-1.4 iron 0.4-1.2 tungsten 0.01-0.3 zirconium 0.02-0.3 copper 0.003-0.1 nickel 0.003-0.1 titanium rest

(RF patent No. 1695696).

Parts and components of rocket and space technology are made from this prototype alloy.

The disadvantages of the alloy and its products are reduced characteristics: tensile strength at 400 ° C (σ _B ⁴⁰⁰ ) and 450 ° C (σ _B ⁴⁵⁰ ); long-term strength for 100 h at 400 ° С (σ ₁₀₀ ⁴⁰⁰ ) and 450 ° С (σ ₁₀₀ ⁴⁵⁰ ) and endurance limit based on 10 ⁷ cycles of a smooth specimen (σ- ₁ ) and a notched specimen (σ ⁿ - ₁ ).

An object of the invention is the creation of an alloy and products from it having enhanced strength characteristics at high temperature and endurance limit.

The stated technical problem is achieved by the fact that the proposed alloy based on titanium containing aluminum, molybdenum, chromium, iron, zirconium, tungsten, which additionally contains silicon and oxygen in the following ratio of components, wt.%:

aluminum 3.0-7.0 molybdenum 1.5-3.0 chromium 0.8-2.3 iron 0.2-0.7 zirconium 0.001-0.095 tungsten 0.001-0.095 silicon 0.16-0.6 oxygen 0.03-0.2 titanium rest

and an article made from it.

The authors found that the introduction of the proposed alloy of a large amount of silicon (0.16-0.6 wt.%) And the introduction of oxygen at the stated content of the remaining components provides an increase in strength characteristics at elevated temperatures and endurance.

In addition, the proposed alloy is cheaper, because does not contain expensive and deficient vanadium.

Examples of specific implementation

In a vacuum-arc method, ingots of the proposed alloy and prototype alloy were smelted. The ingots were forged on presses in several stages after preheating and bars of 25 mm diameter were obtained. Test rods were made from the obtained rods.

Table 1 shows the compositions, and in table 2 the properties of the proposed alloy and alloy prototype. As can be seen from table 2, in the proposed alloy, the tensile strength at 400-450 ° C (σ _B ⁴⁰⁰ , σ _B ⁵⁰⁰ ) increased by 24-28%, the limit of long-term (over 100 hours) strength (σ ₁₀₀ ⁴⁰⁰ , σ ₁₀₀ ⁵⁰⁰ ) increased by 23-27%, endurance limit (σ- ₁ , σ ⁿ - ₁ ) increased by 15%.

Thus, the use of the proposed alloy will reduce the mass of parts and assemblies by 20-25% by increasing the level of strength characteristics at high temperature and increasing the life of structures by increasing the endurance limit.

Table 1 No. Chemical composition, wt.% Al Mo Cr Fe Zr W Si O ₂ Ni V Cu Ti one 3.0 1,5 0.8 0.2 0.001 0.001 0.16 0,03 DOS 2 5.5 2.0 1,5 0.4 0,03 0.1 0.3 0.1 '' - '' 3 7.0 3.0 2,3 0.7 0,095 0,095 0.6 0.2 '' - '' four 5,0 2.2 one 0.7 0.1 0.15 0.02 4,5 0.02 '' - ''

table 2 No. p / p σ _V ⁴⁰⁰ , MPa σ _B ⁴⁵⁰ , MPa σ ₁₀₀ ⁴⁰⁰ , MPa σ ₁₀₀ ⁴⁵⁰ , MPa σ _-1 , MPa σ ⁿ _-1 , MPa; r = 0.75 one 1020 950 990 910 646 450 2 1027 954 995 916 647 470 3 1034 960 998 917 652 490 4 - prototype 820 740 806 715 568 260 σ _B ⁴⁰⁰ and σ _B ⁴⁵⁰ - tensile strengths at 400 and 450 ° C;
σ ₁₀₀ ⁴⁰⁰ and σ ₁₀₀ ⁴⁵⁰ are the limits of long-term (for 100 h) strength at 400 and 450 ° С;
σ _-1 is the endurance limit of a smooth sample based on 10 ⁷ cycles;
σ ⁿ _-1 is the endurance limit of the notched specimen based on 10 ⁷ cycles with a notch radius r = 0.75 mm.

Claims (2)

1. An alloy based on titanium containing aluminum, molybdenum, chromium, iron, zirconium, tungsten, characterized in that it additionally contains silicon and oxygen in the following ratio, wt.%:
aluminum 3.0-7.0 molybdenum 1.5-3.0 chromium 0.8-2.3 iron 0.2-0.7 zirconium 0.001-0.095 tungsten 0.001-0.095 silicon 0.16-0.6 oxygen 0.03-0.2 titanium rest 2. A titanium-based alloy product, characterized in that it is made of an alloy according to claim 1.