Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
WO 2021/251892 PCT/SE2021/050562
1
HOT WORK TOOL STEEL
TECHNICAL FIELD
The invention relates to a matrix type hot work tool steel.
BACKGROUND OF THE INVENTION
Vanadium alloyed matrix tool steels have been on the market for decades and
attained a
considerable interest because of the fact, that they combine a high wear
resistance with
an excellent dimensional stability as well as a good toughness. A matrix tool
steel is a
steel which does not contain any primary carbides or only an extremely low
content of
small primary carbides and which has a matrix consisting of tempered
martensite.
US 3117863 is probably the first patent directed to a matrix steel. The basic
idea in the
US 3117863 was to create a steel having the composition of the matrix of a
known high
speed steel (HS S). The structure of this type of steel was developed in order
to improve
the toughness and the fatigue strength of the steel by refining the
microstructure.
WO 03/106727 Al of the present applicant discloses a hot work matrix steel
having an
excellent toughness and ductility as well as a good hot strength and wear
resistance. The
material is known in the market under the name UN1MAX .
EP1 300 482 Al discloses another matrix steel having a high hardness and wear
resistance in combination with a very high toughness and is therefore
particularly suited
for tools that are stressed at elevated temperatures such as tools for hot and
warm
forming. This steel is known in the market under the name W360 ISOBLOC and
has a
nominal composition of 0.50 %C, 0.20 %Si, 0.25 %Mn, 4.5 %Cr, 3.00 %Mo and 0.60
%V.
Matrix steels are normally produced by vacuum arc re-melting (VAR) or electro
slag re-
melting (ESR) in order to improve the chemical homogeneity and the micro-
cleanliness.
CA 03182089 2022- 12- 8
WO 2021/251892 PCT/SE2021/050562
2
Further examples of hot work tool matrix steels are given in JP2003226939A,
EP3050986A1, US2004/0187972 Al and US2005/0161125A1.
Modern matrix steels are being developed with the aid of software for the
calculation of
phase diagrams and equilibrium phase balances as a function of temperature.
Themo-
Calc (TC) is a user-friendly and frequently used software for this purpose in
order to
find out compositions resulting in a large austenitic single phase area at
soaking
temperatures, because of the fact that the dissolution of possibly existing MC
carbides
formed by segregation during casting is of prima importance.
Hot work matrix steels have a wide range of applications such as die casting
and
forging. The steels are generally produced by conventional metallurgy followed
by
Electro Slag Remelting (ESR). However, a drawback of the known steels is the
limited
wear resistance. In particular, the abrasive wear resistance may limit the
life of the
known steels in demanding hot work operations such as hot forging, extrusion
and press
hardening. These tools are expensive and often need to be welded for repair.
Accordingly, the weldability is of importance. However, the weldability of
tool steel
with high carbon contents is usually considered to be poor and requiring
special
measures such as high preheating temperatures. It would therefore be useful if
the steel
could be welded with standard welding consumables, preferable without
preheating.
DISCLOSURE OF THE INVENTION
The object of the present invention is to provide a matrix type hot work tool
steel, in use
having an improved abrasive wear resistance in demanding applications. In
particular,
the steel should be suited for applications in hot forging, die casting or hot
extrusion. It
should also be suitable for press hardening, in particular for press hardening
of
Advanced High Strength Steel (AHSS). For these applications, the hot wear
resistance
needs to be high.
CA 03182089 2022- 12- 8
WO 2021/251892 PCT/SE2021/050562
3
The tempering resistance is an important property, because in use the steel
may be
subjected to high temperatures for long times. Accordingly, it is preferred
that the steel
not only has a high hardness after hardening but also that the hardness
decrease is small.
Further important properties include high ductility and toughness, which
implies that
the steel should have a high cleanliness with respect to micro-slag, a
complete freedom
from grain boundary carbides as well as a uniform hardness for thicknesses up
to 300
mm.
It should be possible to adjust the hardness over a large interval in order to
optimize the
steel for the intended use. It should also be possible to obtain a high
tensile strength and
yield strength in combination with a sufficient ductility.
The foregoing objects, as well as additional advantages are achieved to a
significant
measure by providing a hot work tool steel having a composition as set out in
the
claims.
The invention is defined in the claims.
DETAILED DESCRIPTION
The importance of the separate elements and their interaction with each other
as well as
the limitations of the chemical ingredients of the claimed alloy are briefly
explained in
the following. All percentages for the chemical composition of the steel are
given in
weight % (wt. %) throughout the description. The amount of the hard phases is
given in
volume % (vol. %). Upper and lower limits of the individual elements can be
combined
freely within the limits set out in the claims. The arithmetic precision of
the numerical
values can be increased by one or two digits. Hence, a value given as e.g. 0.1
% can also
be expressed as 0.10% or 0.100%.
Carbon (0.5 ¨ 0.9 %)
is to be present in a minimum content of 0.5 9/0, preferably at least 0.55,
0.60, 0.66, 0.67,
or 0.68 %. The upper limit for carbon is 0.9 % and may be set to 0.85, 0.80,
0.75, 0.74,
CA 03182089 2022- 12- 8
WO 2021/251892 PCT/SE2021/050562
4
0.73 or 0.72 %. Preferred ranges are 0.6 ¨ 0.8 % and 0.65 ¨ 0.75 %. In any
case, the
amount of carbon should be controlled such that the amount of primary carbides
of the
type M93C6, M7C3 and M6C in the steel is limited, preferably the steel is free
from such
primary carbides.
Silicon (0.03 ¨ 0.8 %)
Silicon is used for deoxidation. Si is present in the steel in a dissolved
form. Si is a
strong ferrite former and increases the carbon activity and therefore the risk
for the
formation of undesired carbides, which negatively affects the impact strength.
Silicon is
also prone to interfacial segregation, which may result in decreased toughness
and
thermal fatigue resistance Si is therefore limited to 08 % The upper limit may
be 07,
0.6, 0.5, 0.40, 0.35, 0.30, 0.28, 0.27, 0.26, 0.25, 0.24, 0.23 and 0.22 %. The
lower limit
may be 0.05, 0.10, 0.11, 0.12, 0.13, 0.14 or 0.15%.
Manganese (0.1 ¨ 1.8 %)
Manganese contributes to improving the hardenability of the steel and together
with
sulphur manganese contributes to improving the machinability by forming
manganese
sulphides. Manganese shall therefore be present in a minimum content of 0.1 %,
preferably at least 0.2, 0.3, 0.35 or 0.4 %. At higher sulphur contents
manganese
prevents red brittleness in the steel. Mn may also cause undesirable micro-
segregation
resulting in a banded structure. The steel shall contain maximum 1.8 %,
preferably
maximum 0.8, 0.75, 0.7, 0.6, 0.55 or 0.5 A.
Chromium (4.0 ¨ 6.6 %)
Chromium is to be present in a content of at least 4 % in order to provide a
good
hardenability in larger cross sections during heat treatment. If the chromium
content is
too high, this may lead to the formation of high-temperature ferrite, which
reduces the
hot-workability. The lower limit may be 4.5, 4.6, 4.7, 4.8 or 4.9 %. The upper
limit may
be 6.0, 5.9, 5.8, 5.7, 5.6, 5.5, 5.4, 5.3, 5.2 or 5.1 %.
Molybdenum (1.8 ¨ 3.5 %)
CA 03182089 2022- 12- 8
WO 2021/251892 PCT/SE2021/050562
MO is known to have a very favourable effect on the hardenability. Molybdenum
is
essential for attaining a good secondary hardening response. The minimum
content is
1.8%, and may be set to 1.9, 2.0, 2.1, 2.15 or 2.2 ?43. Molybdenum is a strong
carbide
forming element and also a strong ferrite former. The maximum content of
5 molybdenum is therefore 3.5 %. Mo may be limited to 2.9, 2.7,
2.6, 2.5, 2.4 or 2.3 %.
Tungsten (W < 0.5 %)
Tungsten is not an essential element in the present invention. The upper limit
is 0. 5 %
may be set to 0.4, 0.3, 0.2 or 0.1 /0.
Nickel (< 1%)
Nickel is not an essential element in the present invention. The upper limit
may be set to
0.5, 0.4, 0.3 or 0.25 %.
Vanadium (1.3 ¨2.3 %)
Vanadium forms evenly distributed primary precipitated carbides and
carbonitrides of
the type VC and V(C,N) in the matrix of the steel. These carbides and
carbonitrides may
also be denoted MX, wherein M is mainly V but Cr and Mo may be present and X
is
one or more of C, N and B. However, in the following only VC will be used with
the
same meaning as MX. Vanadium is used in order to form a controlled amount of
relatively large VC and shall therefore be present in an amount of 1.3 ¨ 2.3
%. The
lower limit may be set to 1.35, 1.4, 1.45, 1.5 or 1.55%. The upper limit may
be set to
2.2, 2.1, 2.0, 1.9, 1.8, 1.7 or 1.65%.
Aluminium (<0.1 %)
Aluminium may be used for deoxidation in combination with Si and Mn. The lower
limit is set to 0.001, 0.003, 0.005 or 0.007% in order to ensure a good
deoxidation. The
upper limit is restricted to 0.1 % for avoiding precipitation of undesired
phases such as
AN. The upper limit may be 0.05, 0.04 or 0.31)/6.
Nitrogen (< 0.12%)
CA 03182089 2022- 12- 8
WO 2021/251892 PCT/SE2021/050562
6
Nitrogen is an optional element. N is restricted 0.12 % in order to avoid too
high an
amount of hard phases, in particular V(C,N). However, the nitrogen content may
be
balanced against the vanadium content in order to form primarily precipitated
vanadium
rich carbonitrides. These will partly be dissolved during the austenitizing
step and then
precipitated during the tempering step as particles of nanometer size. The
thermal
stability of vanadium carbonitrides is considered to be better than that of
vanadium
carbides, hence the tempering resistance of the tool steel may be improved and
the
resistance against grain growth at high austenitizing temperatures may be
enhanced. If
the nitrogen content is deliberately controlled for the above reason then the
lower limit
may be set to 0.006, 0.007, 0.08, 0.09, 0.01, 0.012, 0.013, 0.014 or 0.015%.
The upper
limit may be 0.11, 0.10, 0.09, 0.08, 0.07, 0.06, 0.05, 0.04 or 0.03 %
Copper (< 1%)
Cu is an optional element, which may contribute to increase the hardness and
the
corrosion resistance of the steel. However, it is not possible to extract
copper from the
steel once it has been added. This drastically makes the scrap handling more
difficult.
For this reason, copper is normally not deliberately added. The upper limit
may be
restricted to 0.5, 0.4, 0.3, 0.2 or 0.15 %.
Cobalt (< 5 %)
Co is an optional element. Co causes the solidus temperature to increase and
therefore
provides an opportunity to raise the hardening temperature. During
austenitization it is
therefore possible to dissolve larger fraction of carbides and thereby enhance
the
hardenability. However, Co is expensive and a large amount of Co may also
result in a
decreased toughness and wear resistance. The maximum amount is therefore 5
9/0.
However, a deliberate addition of Co is generally not made. The maximum
content may
be set to 2, 1,0.5 or 0.2%.
Niobium (< 0.1 %)
Niobium is similar to vanadium in that it forms carbonitrides of the type
M(N,C).
However, Nb results in a more angular shape of the M(N,C) and may reduce the
hardenability at high contents. The maximum amount is therefore 0.1 %,
preferably 0.05
CA 03182089 2022- 12- 8
WO 2021/251892 PCT/SE2021/050562
7
A. Nb precipitates are more stable than V precipitates and may therefore be
used for
grain refinement, since the fine dispersion of NbC plays the role of pinning
the grain
boundaries leading to grain refinement and improved toughness as well as
improved
resistance to softening at high temperatures. For this reason, Nb is an
optional element
and may be present in an amount of < 0.1 %. The upper limit may be set to
0.06, 0.05,
0.04, 0.03 0.01 or 0.005 %. The lower limit may be set to 0.005, 0.006, 0.007,
0.008,
0.009 or 0.01 %.
Ti, Zr and Ta
These elements are carbide formers and may be present in the alloy in the
claimed
ranges for altering the composition of the hard phases However, normally none
of these
elements are added. The amount of each element is preferable < 0.5 % 0 . 1 %
or < 0.05
A, more preferably 0.01 % or 0.005 %.
Boron (<0.01 A)
B may be used in order to further increase the hardness of the steel. The
amount is
limited to 0.01 %, preferably < 0.006 % more preferably 0.005 A..
Ca, Mg and REM (Rare Earth Metals)
These elements may be added to the steel in the claimed amounts for modifying
the
non-metallic inclusion and/or in order to further improve the machinability,
hot
workability and/or weldability. The amount of Ca and Mg is preferably < 0.01
%, more
preferably < 0.005 A. The amount of REM is preferably < 0.2 %, more
preferably < 0.1
A or even 0.05 %.
Impurity elements
Impurity elements cannot be avoided during the manufacturing of the steel.
Impurity
elements are therefore included in the balance and the level of said elements
is not
essential to the definition of the present invention.
CA 03182089 2022- 12- 8
WO 2021/251892 PCT/SE2021/050562
8
P, S and 0 are the main impurities, which generally have a negative effect on
the
mechanical properties of the steel. These elements are unavoidable and may
occur in in
the steel at common impurity contents. However, since these elements may have
a
negative effect on the properties in steel, the impurity contents thereof may
be further
limited. Preferred limitations are set out as follows. P may be limited to
0.1, 0.05 or
0.03%. S may be limited to 0.5, 0.1 0.05 0.0015, 0.0010, 0.0008, 0.0005 or
even
0.0001%. 0 may be limited to 0.01, 0.003, 0.0015, 0.0012, 0.0010, 0.0008,
0.0006 or
0.0005 %.
Steel production
The tool steel having the claimed chemical composition can be produced by
conventional metallurgy including melting in an Electric Arc Furnace (EAF) and
further
refining in a ladle, optionally followed by a vacuum treatment before casting.
The
ingots may also be subjected to Electro Slag Remelting (ESR) in order to
further
improve the cleanliness and the microstructural homogeneity of the ingots. In
addition
the steel may also be subjected to Vacuum Induction Melting (VIM) and/or
Vacuum
Arc Remelting (VAR). An alternate processing route for the claimed steel is
gas
atomizing followed by hot isostatic pressing (HIP) to form a HIPed ingot,
which also
may be used in the condition as-HIPed. The ingots may be subjected to further
hot
working to final dimension as well as to soft annealing to a Brinell hardness
of < 360
HBW, preferably < 300 HBW. The Brinell hardness is measured with a 10 mm
diameter tungsten carbide ball and a load of 3000 kgf (29400N) and may also be
denoted HBW10/3000. The steel may be subjected to hardening and tempering
before
being used.
The steel is normally delivered to the customer in the soft annealed condition
having a
ferritic matrix with an even distribution of carbides therein. The soft
annealed steel has
uniform properties also for large dimensions and according to a preferred
embodiment
the uniformity in hardness should have a mean hardness of < 360 HBW and for a
thickness of at least 100 mm and the maximum deviation from the mean Brinell
hardness value in the thickness direction measured in accordance with ASTM E10-
01 is
CA 03182089 2022- 12- 8
WO 2021/251892 PCT/SE2021/050562
9
less than 10 %, preferably less than 5 %, and wherein the minimum distance of
the
centre of the indentation from the edge of the specimen or edge of another
indentation
shall be at least two and a half times the diameter of the indentation and the
maximum
distance shall be no more than 4 times the diameter of the indentation.
The atomized powder may also be used for additive manufacturing.
Hereinafter, the present invention will be described in more detail.
The hot work steel according to the present invention consists of in weight %
(wt.%):
0.5 - 0.9
Si 0.03 - 0.8
Mn 0.1 - 1.8
Cr 4.0 ¨ 6.6
Mo 1.8 ¨ 3.5
V 1.3 - 2.3
Al < 0.1
< 0.12
Ni < 1
< 1
Co < 5
Cu < 1
Nb < 0.1
Ti < 0.05
Zr <0.05
Ta <0.05
< 0.01
Ca <0.01
Mg < 0.01
REM < 0.2
balance Fe and impurities.
CA 03182089 2022- 12- 8
WO 2021/251892
PCT/SE2021/050562
Preferably, the hot work tool steel fulfils at least one of the following
requirements:
0.6 - 0.8
5 Si 0.05 - 0.6
Mn 0.2 - 0.8
Cr 4.4 - 5.6
Mo 2.0 - 2.5
V 1.5 - 1.9
10 Al < 0.05
Ni < 0.5
< 0.5
Co < 2
Cu <0.5
Nb < 0.05
Ti < 0.01
Zr <0.01
Ta <0.01
B 0.006
Ca <0.005
Mg < 0.005
REM < 0.1
More preferably the composition of the steel fulfils one or more of the
following
requirements:
0.65 - 0.75
Si 0.15 - 0.5
Mn 0.4 - 0.5
Cr 4.9 - 5.1
Mo 2.2 - 2.3
CA 03182089 2022- 12- 8
WO 2021/251892 PCT/SE2021/050562
11
V 1.5 - 1.7
Al < 0.03
< 0.05
Ni 0.25
W 0.2
Co <1
Cu <0.2
Nb < 0.005
Ti < 0.005
Zr <0.005
Ta < 0 005
REM < 0.05
Preferably the steel fulfils at least one of the following requirements:
0.66 - 0.75
Si 0.15 -0.25
V 1.52 - 1.68
Al 0.001 - 0.03
N 0.05
< 0.1
Cu < 0.15
In a particular preferred embodiment all of these requirements are fulfilled.
In order to enhance the resistance against abrasive wear the composition can
be adjusted
such that the steel in the hardened and tempered condition contains a small
and
controlled amount of vanadium carbides having a size of larger than or equal
to 1 m.
The size is given as Equivalent Circular Diameter (ECD), which is calculated
from the
image area (A) obtained in an image analysis. The ECD has the same projected
area as
the particle and it is equal to 2-AA/TO.
CA 03182089 2022- 12- 8
WO 2021/251892
PCT/SE2021/050562
12
The steel should preferably contain 0.2 ¨ 4 volume % VC, preferably 0.5 ¨ 3
volume %
and more preferably 1.5 ¨ 2.3 volume %.
The amount of M6C and M7C3 should be restricted to 2 volume %, preferably 0.5
volume %, and more preferably 0.1 volume %, each.
The hardness of the steel can be adjusted by selecting a proper combination of
the
austenitizing time and temperature, the cooling rate expressed as cooling time
in the
temperature interval from 800 C to 500 C (t/8) as well as the tempering
temperature.
Generally, the steel is tempered twice for two hours (2x2h) in order to reduce
the
amount of retained austenite to less than 2 volume %
The mechanical properties of the steel after hardening and tempering to a
hardness of
55-57 HRC should preferably at least one of the following requirements:
Yield strength (Rp0.2): 1700 MPa, preferably 1725MPa, more preferably 1750
lVfPa.
Tensile strength (Rm): 1950 MPa, preferably 2050 MPa, more preferably 2050
MPa, most preferably 2100 MPa.
Elongation (A5)- 3%, preferably 4, more preferably S %, most preferably 6 %
Reduction of area (Z): 5 %, preferably 10, more preferably 15 %, most
preferably
20%.
EXAMPLE 1
Table 1 discloses the hardness in Rockwell C (HRC) as a function of the
hardening
parameters austenitizing time and temperature. It can be seen that the
hardness easily
can be adjusted in the range from 49 to 61 HRC. The composition of the ESR
ingot was
CA 03182089 2022- 12- 8
WO 2021/251892
PCT/SE2021/050562
13
as follows: C 0.71 %, Si 0.22 %, Mn 0.46 %, Cr 5.01 %, Mo, 2.24 %, V 1.62 %,
Al
0.007 %.
Aust.T Time 540 C 560 C 580 C 600 C
610 C
( C) (min)
1050 30 57.3 56.2 54.9 52.4
48.9
1100 30 59.1 58.1 57.5 54.5
52.0
1130 10 60.4 59.1 58.4 55.9
53.7
1150 10 61.2 61.0 59.6 56.7
54.8
Table 1. Hardness (HRC) in the hardened and tempered condition. For all
samples
cooling in vacuum with t8/5 = 300 s and tempering 2x2h.
The temper resistance was examined for the steel austenitized at 1130 C and
tempered
at 580 C and 600 C, respectively. The steel samples were subjected to
heating at 600
C for 10 hours. In the first case the hardness decreased from 58.4 HRC to 53.6
HRC
and for the second sample the hardness decreased from 55.9 HRC to 52.8 HRC.
Hence,
the loss in hardness was 4.8 HRC and 3.1 HRC, respectively.
These values can be compared with the corresponding values for the steel
UNIMAX(''
mentioned in the beginning. A sample of said steel having the nominal
composition C
0.5 %, Si 0.2%, Mn 0.5 043, Cr 5.0 %, Mo 2.3 % and V 0.5 % was prepared. The
steel
was hardened to 57.8 HRC by austenitizing at 1050 C for 30 min, with t815=
300 s and
tempering 2x2h at 540 C. The initial hardness was 57.8 TIRC and the hardness
after 10
hours at 600 C was 49.4 HRC. Accordingly, the loss in hardness was 8.4 HRC
for the
known steel. It can thus be concluded that the inventive steel has a superior
temper
resistance as compared to the known steel.
The cleanliness of the inventive steel was examined with respect to micro-slag
according to ASTM E45-97, Method A, Plate I-r and the result is given in Table
2.
CA 03182089 2022- 12- 8
WO 2021/251892
PCT/SE2021/050562
14
A A
0.5 0 0.5 1.0 0 0 0.5
1.0
Table 2. Cleanliness according to ASTM E45-97, Method A, Plate I-r.
EXAMPLE 2
The ESR ingot of example 1 was hot rolled to a diameter of 196 mm from which
three
samples were taken in the LC2 direction and subjected examination for
mechanical
properties. This steel sample was hardened to a hardness of 56 I-MC by
austenitizing at
1050 C for 30 minutes cooling in vacuum with t8/5= 300 seconds followed by
tempering twice at 560 C for 2 hours. The following mean value of the
examination
are given below:
Yield strength (Rp0.2): 1761 MPa
Tensile strength (Rm): 2117 MPa
Elongation (A5): 7 %
Reduction of area (Z): 26 %
EXAMPLE 3
In this example an inventive steel was compared to a standard matrix steel
used or
forging tools.
The alloys had the following compositions (in wt. %) was
Inventive steel Comparative steel
0.7 0.5
Si 0.2 0.2
Mn 0.5 0.5
Cr 5.0 4.2
CA 03182089 2022- 12- 8
WO 2021/251892
PCT/SE2021/050562
Mo 2.3 2.0
V 1.6 1.2
0.01 1.6
balance Fe and impurities.
5
The alloys were subjected to standard heat treatment, forging and soft
annealing to a
hardness of about 300 HBW. Both steels were subjected to hardening and
tempering by
heating to 1100 C for 30 minutes, quenching and tempering two times at 540 C
during
two hours (2x2h). The hardness of the inventive steel was 57 HRC and the
hardness of
10 the comparative steel was 56 HRC. The wear resistance of the
steel was examined by
the Pin on Disk method using 800 mesh Al-oxide papers from the same batch The
wear
loss of the inventive steel was found to be 178 mg/min and that of the
comparative steel
was 219 mg/min.
15 A further sample of the inventive steel was prepared in order
to obtain the same
hardness as the comparative steel. This was achieved by heating to 1100 C for
30
minutes and tempering 2x2h at 540 C. The hardness was 56 HRC. As expected,
the
wear loss of this sample was somewhat higher (189 mg/min) as compared to the
steel
having a hardness of 57 HRC but substantially lower than that of the
comparative steel
having the same hardness.
EXAMPLE 4
Samples of a steel of the same composition as in example 1 were prepared for
welding tests. Solid blocks of the steel were milled to have a sharp 90
inside corner,
the samples were to two different hardening treatments. The first heat
treatment
consisted of austenitizing at 1050 C for 30 minutes cooling in vacuum with
t8/5= 300
seconds followed by tempering twice at 560 C for 2 hours. The second heat
treatment
differed therefrom in that the austenitizing was performed at 1130 C for 10
minutes.
The samples were then TIG-welded at room temperature (RT), 80 C, 225 C and
325
C using 1.6 mm diameter rod with three different standard welding consumables.
The
CA 03182089 2022- 12- 8
WO 2021/251892
PCT/SE2021/050562
16
applicants own Caldie TIG and ORO 90 TIG as well as UTP A 696 TIG from UTP
Schweissmaterial GmbH.
Cracking was experienced at all temperatures with the consumable Caldie TIG.
However, surprisingly it was found that the two other consumables could be
used to
produce crack-free welding also at RT without cracking. Accordingly, the
inventive
steel possesses a surprisingly good weldability.
INDUSTRIAL APPLICABILITY
The steel of the present invention is useful for hot work applications where
the tool is
subjected to abrasive wear. In particular, the steel is suitable as a tool for
hot forging,
press hardening, die casting, high pressure die casting or hot extrusion.
CA 03182089 2022- 12- 8
