Cemented Carbide, Sandvik new developments and applications
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A key feature of the material is the
potential to vary its composition so that the
resulting physical and chemical properties
ensure maximum resistance to wear,
deformation, fracture, corrosion, and
oxidation. In addition, the wide variety of
shapes and sizes that can be produced
using modern powder metallurgical
processing offers tremendous scope to
design cost effective solutions to many of
the problems of component wear and
failure encountered in both the engineering
and domestic environment.
Engineering MaterialsThe most commonly used materials are
shown schematically relative to their
hardness and toughness properties.
Diamond (PCD) is the hardest, of all,
followed by Cubic Boron Nitride (CBN) and
the Ceramics (Al2O3, SiC, SIALON etc). The
superhard materials all suffer from lower
toughness and poor resistance to sudden
fracture, the Cemented Carbides have a
unique combination of high hardness and
good toughness within a wide range and
thus constitute the most versatile hard
materials group for engineering and
tooling applications.
A unique materialCemented Carbide is one of the most successful compositeengineering materials ever produced. Its unique combinationof strength, hardness and toughness satisfies the mostdemanding applications.
This brochure has been produced to give
engineers a basic understanding of the
unique properties of cemented carbide.
Experience shows that the most effective
product design results from close cooperation
among engineers representing all the
disciplines related to the particular
application.
This approach is especially recommended
when Cemented Carbide is to be used.
The data and graphs shown in this brochure
represent typical values from laboratory
tests and provide an insight into the design
characteristics of the material. Specific
recommendations regarding the selection
of actual grades for any new application
can be made only on the basis of tests and
experience.
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The proportion of carbide phase is normally
70 % to 97 % of the total weight of the
composite and its grain size averages
between 0.2 µm and 20 µm. Tungsten
Carbide (WC), is the most common hard
phase, and Cobalt (Co) alloy, the most
common binder phase. These two materials
The Cemented Carbides are a range of compositematerials, which consist of hard carbide particles bondedtogether by a metallic binder.
Types of Cemented Carbide
form the basic cemented carbide structure
and grades based on this concept are often
referred to in simplified terms as Straight
grades. From this basic concept, many
other types of Cemented Carbide have
been developed. Thus, in addition to these
simple WC-Co compositions, Cemented
Carbide may contain varying proportions
of Titanium Carbide (TiC), Tantalum
Carbide (TaC) or Niobium Carbide (NbC)
and others. These carbides are mutually
soluble and can also dissolve a high
proportion of Tungsten Carbide. In addition,
Cemented Carbides are produced that
have the Cobalt binder phase alloyed with,
WC
-gra
in s
ize,
μm
Cobalt content, % by weight
Oil&Gas drillingand mining,
Mineral andground tools
Rolls
Metal formingand Can Tooling
WoodWorking
WireDrawing
CompositeMachining
MetalCutting
5 10 15 20 25 30
0.5
1
2
3
4
5
10
20
Hardness, Hv3 (HRA)
22002000(94)
1800(93)
1600(92)
1400(90)
1200(88)
1000(86)
800
The application range of straightgrade Cemented Carbides.
or completely replaced by, other metals
such as Nickel (Ni), Chromium (Cr), Iron
(Fe), Molybdenum (Mo), or alloys of these
elements.
Thus, three individual phases may make
up a Cemented Carbide. In metallurgical
terms, the Tungsten Carbide phase (WC) is
referred to as the �-phase (alpha), the
binder phase (i.e. Co, Ni etc.) is the �-phase
(beta), and any single or combination of
other carbide phases (i.e. TiC, Ta/NbC etc)
is the �-phase (gamma).
The Cemented Carbide grades developed
by Sandvik fall into three main groups, as
described on the following pages.
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Types of Cemented Carbide
WC-Co gradesThe grades in this group contain WC and
Co as the main elements, although small
additions or trace levels of other elements
are often added to optimize properties.
These grades are classified according to
their Cobalt content and WC grain size and
are often called the "straight grades". They
have the widest range of strength and
toughness of all the Cemented Carbide
types and this is in combination with
excellent wear resistance. This range of
Cemented Carbides can be subdivided into
its major application areas as follows:
Nano, Ultrafine and Submicron gradesGrades with binder content in the range of
3-10 wt% and grain sizes below 1 µm have
the highest hardness and compressive
strengths, combined with exceptionally
high wear resistance and high reliability
against breakage. These grades are used in
a wide range of wear parts applications
and in cutting tools designed for metallic
and nonmetallic machining for which a
combination of high strength, high wear
resistance and sharp cutting edges are
essential.
Fine and Medium gradesThe grades with binder contents between 6-
30% and grain sizes of 1-3 µm are used in
wear parts and cutting tools when an
element of improved strength and shock
resistance is required.
Medium Coarse, Coarse andExtra Coarse gradesGrades with binder contents between 6-15
wt% and grain sizes above 3µm are used in
oil & gas and mining applications where
resistance to high impact stresses and to
abrasive wear are required.
Nano Ultra Fine Submicron Fine Medium Medium Coarse Coarse Extra Coarse< 0.2 µm 0.2 - 0.5 µm 0.5 - 0.9 µm 1.0 - 1.3 µm 1.4 - 2.0 µm 2.1 - 3.4 µm 3.5 - 5.0 µm > 5.0 µm
Sandvik has a sub-micron WC grain size. It is thebenchmark for leading edge wet drawing of tirecord wire.
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Ultrafine GradesWhen reliability is the king – at 300.000 rpm
– Sandvik Hard Materials has supplied high
performance Cemented Carbide Blanks to
toolmakers in the printed circuit board (PCB)
industry since 1983. During 1986-88 the ultra-
fine grades (UF grades) were developed and
introduced in the market. The ultra-fine
grade family boosted our customers’
productivity and became the market-
leading material for tools in the PCB industry.
Today the trend is towards miniaturization:
digital cameras, lap-tops and mobile phones
are becoming even smaller and are
expected to include more features. This has
resulted in more complex printed circuit
boards with a greater number of
components per surface area. To meet this
demand, PCB manufacturers are compelled
to drill more and smaller holes.
This shift in drill size has increased the
demands on tool material. The smallest drill-
diameter today is only 10-20 µm. To facilitate
the use of tiny drills and raise productivity,
spindles with increasing rpm are being
developed. It is now possible to purchase a
standard PCB NC-machine with a maximum
speed of 300,000 rpm.
To satisfy this new demand from customers,
Sandvik Hard Materials decided to develop
and introduce three new grades for PCB
tooling during 2004.
Ultrafine GradesToday the trend is towards miniaturization: digital cameras, lap-tops and mobilephones are becoming even smaller. To meet this demand, Printing Circuit Boardmanufacturers are compelled to drill more and smaller holes.
Sandvik S870 and S880 are a new
generation of grades that have been
specifically developed for PCB drilling
applications. These grades have been
developed through an extensive research
program, that utilizes an entirely new
patented Cemented Carbide processing
technology. The new process optimizes
reliability, toughness and wear resistance.
Sandvik S870 and S880 exhibit exceptional
performance when sharp edge profiles plus
high wear resistance, toughness and
stiffness are required.
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Leading edge carbide technology for rottary cutting applications
Reliability is often a question of wear resistance, and this is the most outstanding feature of
Cemented Carbide. When the tool must also withstand deformation and high pressure,
Cemented Carbide materials are the only alternatives capable of meeting these
requirements.
Since the performance of a cutting edge depends considerably on these properties,
Sandvik designed the new CRC concept (Carbide Rotary Cutters) with a grade tailored to
fulfill the specific requirements. In order to get sharp cutting edges after grinding and no
chips during use, a controlled fine grain size of the hard phase was developed. The binder
(composition and amount) was also optimized to give that excellent micro toughness
required for this applications.
The combination of the hard phase and binder phase results in a grade with the
appropriate properties. This primarily entails high hardness (to lower the wear of the
cutting edge), high micro toughness (to maintain edge-line integrity and perfect cutting),
very high stiffness (to lower the bending of the cutter and flattening of the cutting edge)
and good thermal conductivity (to reduce temperatures during processing).
The leader in Submicron Cemented Carbides
Sandvik has a long standing leadership in
Submicron Cemented Carbide grades. This is
best exemplified by our grade H10F which
has been the leading grade for a wide range
of cutting applications such as end milling,
drilling, band sawing and paper cutting.
H10F is also our example of Sandvik’s
philosophy of continuous improvement. Raw
materials, powder processing and sintering
conditions have been developed to further
improve H10F’s leading performance.
Submicron gradesSharpness and toughness
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Coarse gradesSandvik manufactures a large variety of inserts usedin extreme drilling and percussion conditions
In today's competitive oil & gas drilling
environment, the pursuit of faster,
economical and superior wells has
conjured a host of technological advances.
However, in the end, it all comes down to
the drilling bit.
Cemented carbide is an ideal material for
drilling inserts due to its high hardness,
compressive strength and thermal
conductivity. R&D within Sandvik Hard
Materials has taken these properties and
used novel techniques to improve the
toughness and impact resistance, whilst
reducing the risk of thermal effects of the
inserts during drilling.
The variety of material that Sandvik can
supply, gives a good coverage of all type of
application needs, for soft rock/heat
generation formations, generally go for the
extra coarse and high binder content. This
results in high fracture toughness and
prolonged insert bit life. For hard formations
is generally use medium coarse and low
binder content grades. This results in high
hardness (better abrasion resistance), but
low fracture toughness has a higher
penetration rate but is more likely to
fracture.
Sandvik manufactures a large variety of
inserts used in rotary & percussion rockbits
for oil & gas and mining industries. Extreme
drilling conditions, whether rotary or
percussion or down the hole require novel
solutions and Sandvik has the technology
to supply the customers with inserts that
perform every time.
Compressive strength rises with decreasing binder content and
smaller grain size. A carbide grade with a small WC grain size and
a low binder content has a typical compressive strength
approaching 7,000 N/mm2.
Like all engineering materials the mechanical strength of Cemented
Carbide is reduced at elevated temperatures. This drop in strength
becomes more significant at temperatures above 600 ºC.
For use at elevated temperatures, grades with cubic carbides and/or
alloyed binder are recomended.
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One of the most useful properties of Cemented Carbide is its extremely high compressive strength.
Mechanical properties of straight WC-Co grades
Relative transverse rupture strength as a function of the temperaturefor an 11% Co, medium WC grain size cemented carbide.
Relative hardness at different temperatures.
Compressive strength as a function of the Co content for different WC grain sizes.
Compressive strength as a function of the temperature for13% Co, coarse grain size carbide.
The main properties used to characterizes, the mechanical properties
of cemended carbide are hardness, transverse rupture strength and
fracture toughness.
The graphs on this page show that hardness increases with
decreasing grain size and binder content. Unfortunately, this will
always be at the expense of reduced toughness. In truly abrasive
applications, hardness is a good measure of wear resistance.
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Hardness as a function of the Co content for various WC grain sizes. Wear resistance as a function of hardness (ASTM B611-85).
Fracture toughness as a function of the Co content for different WC grain sizes.
Wear resistance as a function of the Co content with differentWC grain sizes according to the ASTM B611-85 test method.
Corrosion resistant grades
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This group contains CementedCarbide grades in which thebinder phase has beenspecifically designed to raisecorrosion resistance to a levelexceeding that of the gradesthat contain Co alone as thebinder phase.This is achieved by alloying Cowith elements such as Nickel(Ni) and Chromium (Cr), orcompletely replacing it with amore corrosion-resistant alloy.
The susceptibility of the binder phase of
Cemented Carbides to wet corrosion can
result in wear problems. Corrosion
mechanisms give rise to surface depletion
of the binder phase, permitting the carbide
grains to become detached relatively
easily by the wear process. Awareness of
this situation is important to the selection of
the correct Cemented Carbide for a
particular application.
Cobalt is unsuitable as a binder phase in
wet corrosion conditions. Sandvik has
developed a series of highly corrosion-
resistant grades for these applications.
As illustrated, straight WC-Co grades are
corrosion resistant down to pH 7. This is also
valid for WC-Co grades containing �-phase
(i.e. TiC, TaC and NbC). The highest
corrosion resistance is obtained for the TiC-
Ni grades, which are resistant down to pH1.
However, compared with the straight WC-
Co grades, they have low strength and
inferior thermal conductivity. In addition,
they are difficult to grind and have poor
brazeability, and thus they are used only
when corrosion resistance requirements are
high, combined with low demands in terms
of mechanical strength and thermal shock
resistance.
In most corrosion-wear situations, an
optimum choice are the WC-Ni grades,
which are resistant down to pH 2-3. These
grades retain WC as the hard phase, and
substitute Co for Ni; thus they exhibit
mechanical and thermal properties similar
to the WC-Co grades.
PH value is the most important parameter
when determining the corrosivity of the
environment. However, other factors have
an influence, such as the temperature and
electrical conductivity of the medium. The
latter is dependent on the ion concentration,
meaning the amount of dissolved salts in
the solution. Thus, the ranking of the
corrosivity of an environment is never
certain and, accordingly, general rules are
not valid for all situations.
The Sandvik datasheet “Cemented Carbide
Selection for Corrosion Resistance” is
available as a guide.
It is always recommended that tests be
carried out under actual working conditions
before final selection is made.
Corrosion resistance gradesThe binder phase has been specifically designedto raise corrosion resistance
Corrosion rate as a function of the pH value fordifferent types of cemented carbide tested inbuffered solutions. These tests include a finalsurface wear treatment by tumbling in order toobtain a true value of the depth of the corrodedsurface zone.
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Much of the equipment used in the Oil
& Gas industry is subject to an
aggressive environment that must
not only resist erosion from high
velocity fluids containing sand
particles and other abrasive
media, but it must also be resistant
to corrosion damage. The
combination of these two factors has
caused this industry to migrate
towards using more components that
are made from Cemented Carbide. These
components have natural properties that
tend to resist such wear mechanisms;
however, Sandvik Hard Materials has
dramatically improved the resistance to
erosion and corrosion by focusing on the
binder phase of grades used in this field.
In order to improve the wear characteristics
of the Cemented Carbide grades used
specifically for choke valves in this
industry, multi binder (Ni, Cr, Mo, and Co)
corrosion-erosion resistant materials were
introduced. Today, there are more than
100 choke control valves in service using
Corrosion resistant gradesHave contributed to an improvement of up to 5 timesservice life compared to conventional grades
The first choice material in hostile environments
these Cemented Carbide grades operating
in sub-sea and other extreme environments.
These materials have contributed to an
improvement of up to 5 times service life
when compared to conventional grades.
Sandvik Hard Materials has now taken this
performance increase to another level.
Based on feedback gained from the field
and the experiences of equipment design
engineers working with these grades,
Sandvik has carried out development work
focused on improving material toughness
and strength. Success has been achieved
by carefully optimizing the relationship
between wear (material hardness) and
toughness for the multi-binder materials
without any loss of resistance to corrosion-
erosion.
As a result, Sandvik has developed the next
generation of multi-binder grades, such as
AM12.
As always, tests have been carried out with
an industry partner to verify the increased
performance.
DZ10An outstanding performance compared to standard grades to produce both aluminium and steel cans
Failure mechanism of classical WC-Co
carbide punches used for production of two
piece beverage cans by Draw and Wall
Ironing is mainly due to leaching of the
binder phase. DZ family grade (sub-micron
carbide grains combined with the
appropriate binder) has been tailored to
fulfill the specific requirements of the can
tooling industry. This means a material
with very high wear and corrosion
resistance. The shift from the classical
grade used in the field to the specific DZ10
grade has brought many valuable
improvements. Life times have been tripled
and wear reduced, allowing more regrinds
per punch.
After 19 million cans a wear of 0,002 mm
(.0000079") was found for the DZ10 punch
while 0.007 mm (.0000275") was found for
standard grades after only 14 million cans.
Another example of profitable cooperation
between Sandvik and our key customers.
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Cubic and Cermet grades
Cubic and cermet grades are one of the
latest developments for Sandvik Hard
Materials. This group consists of grades
containing a significant proportion of
�-phase, (i.e. TiC, TaC, NbC etc.) together
with WC and Co.
The main features of the �-phase are good
thermal stability, resistance to oxidation
and high temperature wear. These grades
are designed to provide a favorable
balance of wear resistance and toughness
in applications that generate high
temperatures and entail close contact with
ferrous materials. These conditions arise in
metal cutting or high-pressure sliding
contact situations involving the welding
and galling of surfaces.
Saw tips made from Sandvik’s Cermet
grade CE01 for metal sawing/ metal
cutting are designed especially for saws
that do not use coolants. The working
material – conventional and low
carbon steels–interacts with the saw tips
in different ways during extreme
working conditions.
The Cermet grade CE01 offers high
oxidation/ corrosion resistance to
maintain edge sharpness. To ensure
edge retention during sawing, high
wear resistance plus high toughness
are of crucial importance for the
Cermet CE01 tips. Brazeability and
grindability also are key properties
when manufacturing saw blades.
Cermet CE01 tips are surface-treated to
maintain optimal surface conditions for
brazing and a high micro-toughness
for good grindability.
Other common terms for these grades are
the “metal-cutting” or “mixed-crystal” grades.
In the extreme case, these grades are
designed without any WC phase. Such
hard metal grades are called cermets and
give a unique combination of high
temperature hardness, chemical wear
resistance and low density. Cermets are
traditionally avoided for wear parts because
of being more brittle than standard WC-Co
grades. New developments have allowed
toughness to be improved significantly
and cermets are now applied in a number
of demanding applications from advanced
engineering components to high perfor-
mance metal sawing blades.
WC-Co Cubic Cermet
Optimized performance at extreme working conditions
Sandvik Hard Materialsexperience Cubic and Cermet grades
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Challenging the futureTailoring solutions to a wide variety ofautomotive applications
Sandvik Hard Materials has been
developing and supplying solutions for the
automotive industry for over two decades.
Our extensive knowledge of cemented
carbide and related cermets allows us to
tailor solutions to a wide variety of
automotive applications. Our components
are incorporated into systems used world-
wide by the leading automotive companies
and suppliers.
One example of how our materials
challenge the conventional thinking is our
unique ability to produce components that
fullfill all technical requirements while
being only a fraction of the size of a similar
component produced in steel.
Cemented carbide is commonly perceived
as a cutting tool or wear part material.
While cemented carbide is ideally suited for
cutting and wear applications limiting your
view to only these areas is far too
restrictive. In reality, cemented carbide
and cermets offer a wide range of
properties making them very well suited for
the new challenges of the automotive
industry.
The four steps toward the final cemented carbideproduct: powder composition, powder compacting,sintering and machining/grinding.
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Research and development in Cemented CarbideFrom raw material to your needs, Sandvik develops Cemented Carbide technology to meet our present and future customer needs.
From atomic engineering of crystal grain
boundaries to the customer-specific design
of a rotary cutting station; Sandvik
Research and Development is dedicated to
advancing the frontiers of cemented
carbide technology in order to meet our
customers’ present and future needs. Every
stage in the manufacture of a cemented
carbide component – from powder
production to finishing – is crucial to
Our peopleSandvik employs around 150 engineers,
technologists and technicians at centres in
Sweden, the UK and France, dedicated to
R&D of hard materials.
These people work closely with our
customers through our global product-
specialist networks to ensure our R&D is
focused on application and customer
requirements. The application know-how
gained through these networks in key
business areas enables us to work together
to create the best materials for each
application.
General Notes/Recommendations:The properties and data listed in this brochure represent average values based on laboratory testsconducted by Sandvik. They are indicative only of the results obtained in these tests and should not beconsidered as guaranteed values. Any statements in this brochure referring to a specific alloy for aparticular application, or to the use of a product, are solely recommendations based on tests or experience.Such statements cannot be considered as warranties/guarantees. Products, and any recommendedpractices, should always be tested by the user, under actual service conditions, in order to confirm theirsuitability for an application.
ensuring optimum performance.
At Sandvik, we take pride in having full
control of each processing step and in
developing proprietary production
processes that further improve our
technological capabilities. Our mission is to
develop new products and new grades
that enhance our customers’ operations
through superior performance and reduced
costs.
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Our performance
Although it is more than 80 years since the
first cemented carbide material was
marketed, the pace of development in the
field remains rapid. Sandvik is at the
forefront of this development, issuing 20 to
30 cemented carbide-related patents and
releasing 5 to 10 new grades with
improved performance every year.
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