Alloy VT20
Designation
Name |
The value |
Designation GOST Cyrillic |
ВТ20 |
Designation GOST Latin |
BT20 |
Transliteration |
VT20 |
The 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 metals, and their alloys |
В51 |
GOST 19807-91, OST 1 90000-70, OST 1 90013-81, OST 1 90002-86 |
Sheets and stripes |
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 |
Bulls. Blanks. Slabs |
В31 |
OST 1 90426-92 |
Sectional and shaped rolling |
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 |
Pipes from 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 |
The 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 |
The 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 characteristics
Section, mm |
sT|s0,2, MPa |
σB, MPa |
d5, % |
d |
y, % |
kJ/m2, кДж/м2 |
Brinell hardness number, 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 |
Section |
Section |
sT|s0,2 |
Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2% |
σB |
Limit short-term strength |
d5 |
Elongation after rupture |
d |
Elongation after rupture |
y |
The relative narrowing |
kJ/m2 |
Toughness |
HRC |
Rockwell hardness (indenter diamond spheroconical) |
Physical characteristics
Temperature |
Е, ГПа |
r, кг/м3 |
l, Вт/(м · °С) |
R, НОм · м |
a, 10-6 1/°С |
С, Дж/(кг · °С) |
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 |