RU2210612C2 - Titanium-based alloy and product prepared therefrom - Google Patents

Abstract

FIELD: nonferrous metallurgy. SUBSTANCE: invention provides titanium-based alloy containing, wt %: aluminum 10-12, niobium 38-42, molybdenum 0.5-1.0, zirconium 1-1.5, silicon 0.1-0.25, and additionally vanadium 1-1.5, and carbon 0.05-0.08. EFFECT: increased low-temperature specific strength and plasticity and high-temperature specific instant and long-term (100 h at 650 C) strength. 3 cl, 2 tbl

Description

 The invention relates to the field of metallurgy, in particular to titanium-based alloys operating at elevated temperatures.

Known alloy based on titanium [1], having the following composition, wt.%:
Al - 9.3 - 14.2
Nb - 32 - 60.5
V - 0.24 - 6.2
Ti - Else
Elements of engine structures operating at temperatures of 550-650 ^o C. are made from a known alloy.

The disadvantage of the alloy is low heat resistance - long-term strength for 100 hours at temperatures up to 650 ^o C. Products made from a well-known alloy have a limited service life at operating temperatures.

The closest analogue taken as a prototype is an alloy based on titanium [2] having a chemical composition, wt.%:
Al - 8.2 - 11.81
Nb - 31.7 - 43.8
Mo - 0 - 3.23
Ta - 0 - 6.1
Zr - 0 - 3.0
Si - 0 - 0.38
Ti - Else
The prototype alloy does not have sufficiently high values of the specific tensile strength, ductility (relative elongation) at room temperature and specific short-term and long-term strength for 100 hours at temperatures up to 650 ^o C. Structural elements made of the prototype alloy have a limited resource.

An object of the invention is to increase the specific strength and plastic characteristics at a temperature of 20 ^o C and specific short-term and long-term strength for 100 hours at a temperature of 650 ^o C.

To achieve the technical task, an alloy based on titanium is proposed, including aluminum, niobium, molybdenum, zirconium, silicon, which additionally contains vanadium and carbon in the following ratio of components, wt.%:
Al - 10 - 12
Nb - 38 - 42
Mo - 0.5 - 1.0
Zr - 1 - 1.5
Si - 0.1 - 0.25
V - 1 - 1.5
C - 0.05 - 0.08
Ti - Else
and an article made from it.

From the proposed alloy can be made engine parts (for example, blades, disks and compressor rings), long-term operating at temperatures of 550-650 ^o C.

The authors found that additionally introduced into the titanium-based alloy with the stated ratio of components V and C form complex carbosilicides [(Ti, Zr, V) ₅ (Si, C) ₃ and (Ti, Zr, V) ₃ (Si, C) ₂ ], which in the form of dispersed precipitates strengthen the alloy, increasing it both low-temperature specific strength and ductility, and high-temperature specific short-term and long-term strength for 100 hours at a temperature of 650 ^o C.

 Examples of implementation.

 The ingots of the proposed alloys were made according to the production technology of titanium alloys, which included the manufacture of a consumable electrode from charge materials and the smelting of ingots by multiple vacuum-arc remelting.

 The compositions of the proposed alloy (1-3) and alloy prototype 4 are shown in table 1.

 Machined cast billets were forged and rolled in order to obtain 2 mm thick semi-finished products. Semi-finished sheet products were subjected to heat treatment, cutting into billets, from which test samples were made. The properties of the proposed alloy (1-3) and alloy prototype 4 are shown in table 2.

As can be seen from table 2, the proposed alloy is superior at a temperature of 20 ^o With in specific short-term strength by 16.3-18.3%, in ductility by 13-21%, and at a temperature of 650 ^o With in specific short-term strength by 14-17 , 1% and specific long-term strength in 100 hours by 43.4-50% alloy prototype.

 Using the proposed alloy will reduce the weight of the structure, increase the technical resource and ensure the reliability of the structure.

Literature
1. US patent 5205984.

 2. Patent EP 0924308.5

Claims (1)

1. An alloy based on titanium, including aluminum, niobium, molybdenum, zirconium, silicon, characterized in that it additionally contains vanadium and carbon in the following ratio of components, wt. %:
Al - 10-12
Nb - 38-42
Mo - 0.5-1.0
Zr - 1-1.5
Si - 0.1-0.25
V - 1-1.5
C - 0.05-0.08
Ti - Else
2. The product is made of an alloy based on titanium, characterized in that it is made of an alloy of the following chemical composition, wt. %:
Al - 10-12
Nb - 38-42
Mo - 0.5-1.0
Zr - 1-1.5
Si - 0.1-0.25
V - 1-1.5
C - 0.05-0.08
Ti - Else

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