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Page 1: Synthesis of Ti-Al-V alloys by Aluminothermic Reduction to Produce Pressed ... · M e t a l l u r g i e P r o z e s s t e c h n i k Recycling Synthesis of Ti-Al-V alloys by Aluminothermic

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Recycling

Synthesis of Ti-Al-V alloys by Aluminothermic Reduction

to Produce Pressed Electrodes for ESR

Dipl.-Ing Siran Hassan Pour

IME Process Metallurgy and Metal Recycling

RWTH Aachen University, 52056 Aachen, Germany

Prof. A.D. Ryabtsev, Prof. A.A. Troyansky

Department of Electrometallurgy

Donetsk National Technical University, Ukraine

3223

2

3

4OAlTiAlTiO

32526

5

3

5

2

1OAlVAlOV

3243

4

3

8OAlKClAlKClO

Booster reaction

Vanadium oxide reduction

Titanium dioxide reduction

Text

ATR - production ESR - refining

Pressing

Electrodes ATR Master Alloy Electroslag Remelting 1 2 3

Motivation

reactor lining based on Al2O3

charged material as powder

electrical ignition from

mixture surface

self-propagating reaction

through entire mixture

settling of metal phase at

reactor bottom

due to high material and production costs alternative production processes

are highly demanded

aluminothermic reduction offers a least expensive process through:

high temperatures

short reaction times

self-propagating reaction behavior

direct synthesis of titanium alloy by co-reduction of alloying element oxides

reduced production costs via decreasing amount of Titanium sponge

reactor

reaction front propagation

slag

metal

reactor

metal slag separation

ATR Process

determination of β

for master alloy

Ti-6βAl-4βV

definition of process

window by adjusting

adiabatic reaction

temperature

reaction enthalpy

phys. properties of

input material

TiO2

Al

CaO

ATR product

metal cross section

chrushed ATR metal

Titanium sponge

Ti-6Al-4V compact

Process Idea

kJH R

Ti 1,184

kJH R

OV 1,62152

kJH R

KClO 3,22414

0

2

4

6

8

10

0

10

20

30

40

50

0,8 1,2 1,6 2 2,4 2,8

O in

wt.

-%

Al in

wt%

Al/TiO2 (molar ratio)

AlO

Al-O-interaction in TiO2 reduction

Vanadium decreases

oxygen content in ATR

metal to 2900 ppm

ESR slag system

CaF2-CaO-Ca

V2O5

KClO4

adding Ti-sponge

to obtain

Ti-6Al-4V

Ti-sponge acts as

binder

high binder

content required

high ATR metal

input favored

lab-scale ESR unit

power supply: 724 kW

electrode weight: 1,0 kg

protective argon atmosphere

used slag system CaF2-CaO-Ca

monitoring of metal droplet

transfer during remelting

process

deoxidation target < 500ppm

β = 4: Ti-26Al-16V

β = 5: Ti-30Al-20V

TiAl produced

via ATR 0

5000

10000

15000

20000

4 5

O in

wt.

%

β in Ti-6βAl-4βV

TiAl

β

107

TiAl

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