Boloc - Duroc AB

09-09-05
Boloc
Cold rolled annealed Boron steel
for hardening in water or oil
Definition
The Boloc Steel Grades are a group of hardenable, fine grained
weldable steel. The Boloc Steel Grades are precision rolled
and Open Coil Annealed giving fine tolerances and extra even
properties throughout the band. It may well replace grades
with medium high and high carbon content for applications
where high strength, hardness, toughness and wear resistance
are required.
Welding
Boron Steel Grades are usually welded in the same way as conventional
high strength steels. Welding methods and filler metals
producing low hydrogen contents should be used. The welds
should, if possible, be placed in those areas of the construction,
where the load is the lowest. The transition between weld and
base material should be made as mooth as possible, e.g. by TIGtreatment.
Hardening/Cutting/Punching
See Technical Report MAS 5:1 respectively MAS 5:2
Delivery condition
Unannealed or annealed.
Other information
The Boron Steel Grades are characterized by good formability.
They can be bent to a small radius in the annealed condition.
They also show good toughness and tempering after hardening
can be omitted in most cases. Additional information can be obtained
from Duroc Special Steel AB, Technical customer service.
Chemical composition
Steel grade C Si Mn P S Cr B
% % % % % % %
min–max min–max min–max max max min–max min–max
Boloc 02 0.20 – 0.25 0.20 – 0.35 1.00 – 1.30 0.030 0.010 0.140 – 0.260 0.0015 – 0.0050
Boloc 03 0.25 – 0.30 0.20 – 0.35 1.00 – 1.30 0.030 0.010 0.150 – 0.250 0.0015 – 0.0050
Boloc 04* 0.25 – 0.30 0.20 – 0.35 1.00 – 1.30 0.030 0.010 0.400 – 0.600 0.0015 – 0.0050
*Calcium treated (gives equally good cold forming properies in all directions).
Mechanical properties
Steel grade Condition Yield strength Tensile strength Elongation Hardness
R e
N/mm 2 ca R m
N/mm 2 ca A 80
% ca HV ca
Boloc 02 Annealed 340 480 28 140
Boloc 03 Annealed 360 500 27 150
Boloc 04 Annealed 370 510 26 155
Steel grade Condition Cooling media Tensile strength Elongation Hardness
R m
N/mm 2 ca A 80
% ca HV ca
Boloc 02 Hardened Oil 1 370 8 450
Water 1 590 6 520
Boloc 03 Hardened Oil 1 410 6 480
Water 1 650 4 540
Boloc 04 Hardened Oil 1 430 6 490
Water 1 675 4 560
Duroc Special Steel AB · 971 88 Luleå · Tel +46 920 43 22 00 · Fax +46 920 255 856 · www.duroc.se/specialsteel

September 2009
The particulars in this data sheet are correct at the time of going
to print and are intended to give general guidance for the use of
the product. Subject to changes arising from continual product
development. The information and data must not be regarded as
guaranteed values, unless specially confirmed in writing.