Alloy VT20

Designation

Name The value
Designation GOST Cyrillic ВТ20
Designation GOST Latin BT20
Transliteration VT20
By chemical elements ВTe20

Description

Alloy VT20 is used: for the manufacture of semi-finished products (sheets, strips, foils, strips, plates, bars, rods, profiles, pipe shells and pipe, forgings and forged blanks with a thickness up to 250 mm) by the deformation and bars; welded rings from hot rolled and extruded sections and rolled ring; corrosion-resistant parts, long operating at temperatures up to +500 °C; for the manufacture of the aircraft wing panels, parts, and welded assemblies, continuously operating at temperatures from -70 to +450 °C (6000 h), to +500 °C (3000 hrs.).

Note

A pseudo-alloy VT20 belong to the system Ti-Al-Zr-Mo-V. a Fairly high aluminum content provides significant strength and heat resistance of this alloy. Its ductility and workability during processing pressure lower than that of alloys OT4. However, it is well deformed in the hot state. In the sheet embodiment, this heat-resistant alloy in the second alloy ВТ18У. The alloy is well welded by all welding processes used for titanium alloys. Mechanical properties of welded joints are not inferior to the properties of the base metal. The VT20 alloy can be welded with a titanium alloy VTZ-1, OT4, OT4−1, VT5−1, VT6, VT14, ВТ5Л, ВТ21Л. This alloy is supplied in the form of shaped castings under the brand name ВТ20Л.

Standards

Name Code Standards
Non-ferrous metals, including rare, and their alloys В51 GOST 19807-91, OST 1 90000-70, OST 1 90013-81, OST 1 90002-86
Sheets and strips В53 GOST 22178-76, GOST 23755-79, OST 1 90218-76, OST 1 90024-94
Bars В55 GOST 26492-85, OST 1 90266-86, OST 1 90173-75, OST 1 90107-73, OST 1 90006-86
Blanks. Of the workpiece. Slabs В31 OST 1 90426-92
Bars and shapes В52 OST 1 92039-75, OST 1 92051-76, OST 1 92064-77, OST 1 90105-73, OST 1 90313-81, OST 1 90320-82, OST 1 90325-82, OST 1 90328-82
Tubes of non-ferrous metals and alloys В64 TU 1-5-127-73

Chemical composition

Standard C Si Fe N Al V Ti Mo O Zr H
GOST 19807-91 ≤0.1 ≤0.15 ≤0.25 ≤0.05 5.5-7 0.8-2.5 Rest 0.5-2 ≤0.15 1.5-2.5 ≤0.015
OST 1 90013-81 ≤0.1 ≤0.13 ≤0.25 ≤0.05 5.5-7 0.8-2.5 Rest 0.5-2 ≤0.15 1.5-2.5 ≤0.015
Ti is the basis.
According to GOST 19807-91 and OST 1 90013-81 the total content of other impurities is ≤ 0.30%. The mass fraction of hydrogen is indicated for ingots. In the alloy, a partial replacement of molybdenum by tungsten in an amount not exceeding 0.3% is allowed. The total mass fraction of molybdenum and tungsten should not exceed the norms specified in the table for molybdenum. The mass fraction of chromium and manganese should not exceed 0.15% (in total). The mass fraction of copper and nickel should not be more than 0.10% (in total), including nickel not more than 0.08%.

Mechanical properties

Section, mm sT|s0,2, MPa σU, MPa d5, % d y, % KCU, kJ/m2 HB, MPa HRC
Ring welded at OST 1 90320-82
5-10 - 930-1130 ≥8 - - ≥392 - -
Sheet metal in delivery condition (the samples across the direction of rolling)
- - ≥638 - - - - - -
Ring welded at OST 1 90320-82
10-20 - 930-1130 ≥6 - - ≥392 - -
Forgings weighing up to 200 kg after annealing
- - ≥638 - - - - - -
Ring welded at OST 1 90320-82
5-10 - 880-1130 ≥6 - - ≥245 - -
Bars and rods, hot-rolled. Annealing
- - ≥687 - - - - - -
Ring welded at OST 1 90320-82
10-20 - 880-1130 ≥4.5 - - ≥245 - -
Bars and rods, hot-rolled. Annealing
- - ≥569 - - - - - -
Ring welded at OST 1 90325-82
- - 930-1180 ≥10 - ≥25 ≥343 - -
- - 880-1180 ≥5 - ≥12 ≥245 - -
Ring welded at OST 1 90328-82
5-10 - 930-1130 ≥8 - - - - -
10-20 - 930-1130 ≥6 - - ≥392 - -
5-10 - 880-1130 ≥4 - - - - -
10-20 - 880-1130 ≥3 - - ≥196 - -
Sheet metal in delivery condition (the samples across the direction of rolling)
0.8-4 - 980-1180 ≥9 - - - - -
4-10.5 - 980-1180 ≥6 - - - - -
Rolled sheet after annealing (samples across the direction of rolling)
0.8-1.8 - 930-1130 ≥12 - - - - -
1.8-4 - 930-1180 ≥10 - - - - -
4-10.5 - 930-1180 ≥8 - - - - -
The blades of aircraft engines is made by forging, by forging with the use of thermo-mechanical processing and the method of forging in isothermal conditions, including the conditions of superplasticity after annealing (compact (M) - the projected area cm2 20-250, medium (C) - 250-550 cm2, bulk (K) - 550-1500 cm 2)
М, С, К - 930-1130 ≥10 - ≥25 ≥392 255-341 28-38.5
Plate in the delivery condition according to GOST 23755-79. Annealing (samples transverse)
11-60 - 900-1130 - ≥6 ≥12 ≥294 - -
60-100 - 880-1130 - ≥5 ≥10 ≥294 - -
Plate on OST 1 90024-94 in the delivery condition. The annealed samples (transverse)
11-60 - 930-1130 - ≥6 ≥12 ≥294 - -
60-100 - 885-1130 - ≥5 ≥10 ≥294 - -
Forgings weighing up to 200 kg after annealing
101-250 - 883-1128 ≥8 - ≥20 ≥294 255-341 -
100 - 932-1128 ≥10 - ≥25 ≥392 255-341 -
Bars hot rolled autogenie ordinary quality GOST 26492-85 (longitudinal samples)
10-12 - ≥885 ≥8 - ≥20 - - -
100-150 - ≥885 ≥8 - ≥20 ≥245 - -
12-100 - ≥885 ≥7 - ≥20 ≥294 - -
Bars hot rolled autogenie high-quality according to GOST 26492-85 (longitudinal samples)
10-12 - 930-1130 ≥10 - ≥25 - - -
100-150 - 885-1130 ≥8 - ≥20 ≥294 - -
12-25 - 930-1130 ≥10 - ≥25 ≥294 - -
25-100 - 930-1130 ≥10 - ≥25 ≥392 - -
Forged square bars and round after annealing
140-250 - 883-1128 ≥8 - ≥20 ≥294 255-341 -
- 932-1128 ≥9 - ≥25 ≥392 255-341 -
The bar in the state of delivery
≥840 950-1150 ≥10 - ≥25 ≥450 255-341 -
The tubular billet. Annealing
15х15 ≥736 932-1128 ≥10 - ≥25 ≥392 - -

Description mechanical marks

Name Description
sT|s0,2 Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2%
σU Limit short-term strength
d5 Elongation after rupture
d Elongation after rupture
y The relative narrowing
KCU Toughness
HB Brinell hardness number
HRC Rockwell hardness (indenter diamond spheroconical)

Physical characteristics

Temperature Е, HPa r, kg/m3 l, W/(m · °C) R, Mr. · m a, 10-6 1/°C С, J/(kg · °C)
20 112 4450 8 1110 - -
100 - - 88 - 83 -
200 - - 102 - 83 587
300 - - 109 - 9 628
400 - - 122 - 92 67
500 - - 138 - 93 712
600 - - 151 - 95 -

A description of the physical symbols

Name Description
Е The normal elasticity modulus
r Density
l Coefficient of thermal conductivity
R UD. the resistivity
С Specific heat

Technological properties

Name The value
Weldability without restrictions