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VRN
500 Abrasion Resistant Steel Plate
VRN 500 is a quenched and tempered high-strength alloy steel which has
superior abrasion resistance, micro-cleanliness, and toughness. This
steel is an advancement on VRN 360 and VRN 400 grades.
The superiority of VRN 500 is due to desulpherisation and inclusion shape
control characteristics.
| 1.
CHEMICAL COMPOSITION (TYPICAL) |
C.
0.35
(Max.) |
Mn.
1.60
(Max.) |
Si.
0.55
(Max.) |
P.
0.03
(Max.) |
S.
0.03
(Max.) |
Cr.
0.4-
1.2 |
Mo.
0.1-
0.5 |
V
0.1
(Max.) |
Ti.
0.02
(Max.) |
B.
0.004
(Max.) |
2.
MECHANICAL PROPERTIES. (TYPICAL VALUES)
2.1
Hardness.
The hardness range is as follows:
Brinell H.N.
Rockwell C
V.H.N. |
477 - 550
49 - 54
523 - 610 |
2.2 Tensile Strength.
VRN 500 is produced to meet specific minimum surface hardness requirements
and not tensile requirements, however typical stress strain data is as
follows:
Tensile Strength
1 880 MPa max.
Yield Strength
1 650 MPa max.
Elongation (50 mm)
14 %
R.A. at point of fracture
35%
2.3
Charpy V. Notch Impact Resistance Tests.
(Typical Value)
50-60 Joules at Ambiant
Temperature.
3.
FABRICATION
3.1
Cold Forming.
Limited Cold forming may be performed on VRN 500.
Edge preparation by grinding is advised.
Flame cut edges should be tempered at 200oC max. prior to
grinding the edges if difficult radii are to be encountered.
N.B.
Major forming should be done transverse to the rolling direction and not
parallel to it.
3.2
Flame Cutting.
Modern flame cutting practice may be employed, however it is advisable to
pre-head from 65 to 120 degrees C immediately ahead of the torch.
3.3
Hot-working.
VRN 500 is tempered at a temperature of 200-400 degrees C and to ensure
that full hardness is retained, the steel should therefore not be hot
worked at temperatures exceeding 250 degrees C.
3.4
Drilling.
Alternative attachment methods such as hole fabrication with oxy-fuel
process or stud welding should be considered. Drilling of this plate
is difficult and costly.
4.
Welding
When welding the wear and
abrasion resistant steels the risk of hydrogen induced cracking (delayed
cracking or cold cracking) must be minimised. The presence of hydrogen,
combined with stresses in the welded joint, are the main cause of this
type of cracking.
The risk of cracking can be
minimised by:
* ensuring that the
surfaces to be welded are dry and free of any contamination.
* applying the correct
preheat. Preheating is most important in tack welding and in welding the
root run. The recommendations as laid out in EN1011 should be applied
while considering the higher hardness and strength of these steels
* minimising the shrinkage
stresses caused by welding. This can be achieved by ensuring a good fit
between the workpieces and a well planned sequence of
weld runs (balanced welding).
* selecting a filler metal
with a low hydrogen content. HD ≤ 5ml / 100g.
5. Applications
VRN 500 steel plate is one of the hardest known rolled quenched and
tempered plates. This steel will reduce material handling costs to a
minimum for earth moving, mining and other similar industries in which a
combination of toughness and abrasion resistance is required. Wear
plates for truck bodies, chute liners and storage-bin liners are typical
applications. When working with these steels it is important that the
fabricator is fully aware of their properties and understands the
necessary fabrication techniques.
Please
contact the Technical Department at Macsteel VRN if
there are any queries.
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