|
NITROGEN:
ENHANCES VANADIUM STRENGTHENING
In the presence
of vanadium, nitrogen is converted from an impurity into a cost-effective
alloying element. Vanadium and nitrogen combine rapidly, forming
vanadium nitrides that are more stable and more finely dispersed
than vanadium carbides. For that reason, precipitation strengthening
with vanadium is more efficient when nitrogen is present..
Same
Strength with Less Vanadium
By
increasing strength, nitrogen allows steelmakers to use less vanadium,
as shown in the graph above. Here, a 0.07% vanadium addition is
needed to obtain a 110 MPa (16 ksi) increase in yield strength
in a steel containing only 50 parts per million of nitrogen. If
the nitrogen content is increased to 100 parts per million, only
0.04% vanadium is needed to obtain the same yield strength.
Substantial
Savings
Reducing
vanadium additions yields major cost savings. In the example below,
equivalent yield strengths are obtained when either 0.10% vanadium
is added as ferrovanadium or 0.06% vanadium is added as Nitrovan®
vanadium. Using Nitrovan® vanadium reduces vanadium additions
by 0.40 kg (0.90 lbs.) per metric ton of steel.
Equivalent
Yield Strengths with Less Vanadium
| |
VANADIUM
USED
|
VANADIUM
SAVINGS
Per Metric Ton of Steel Using Nitrovan® Vanadium Instead
of Ferrovanadium
|
|
ALLOY
USED
|
VANADIUM
ADDITION
Per Metric Ton
|
VANADIUM
CONTENT
In Steel
|
|
Nitrovan®
Vanadium
|
0.60
kg
(1.35 lbs.)
|
0.06%
|
0.40 kg
(0.90 lbs.)
|
|
80%
Ferrovanadium
|
1.0
kg
(2.25 lbs.)
|
0.10%.
|
|
