Comparison of high speed steel and tungsten carbide

What is tungsten carbide? Tungsten carbide is a chemical compound containing
equal parts of tungsten and carbon atoms. High-speed steel (HSS or HS) is a
subset of tool steels. According to the chemical composition, high-speed steel
can be divided into tungsten and molybdenum steel. According to the cutting
performance, it can also divided into high performance high speed steel and
common high speed steel.

Properties comparison of high speed steel and tungsten carbide:

Tungsten carbide is approximately two times stiffer than high speed steel, with
a Young’s modulus of approximately 550 GPa, and is much denser than steel or titanium.

tungsten carbide

High speed steel must be strengthened by The heat treatment. Under the condition
of quenching, chromium, iron and carbon forming a extremely hard carbide. The
extremely carbide can improve the wear resistance of steel.

high speed steel

Sintered tungsten carbide cutting tools are very abrasion resistant and can also
withstand higher temperatures than standard high speed steel tools. Carbide cutting
surfaces are often used for machining through materials such as carbon steel or
stainless steel, as well as in situations where other tools would wear away, such
as high-quantity production runs.

Application comparison of high speed steel and tungsten carbide:

High speed steel is commonly used in tool bits and cutting tools. It is often used
in power-saw blades and drill bits.  It is superior to the older high-carbon steel
tools used extensively through the 1940s in that it can withstand higher temperatures
without losing its temper (hardness). This property allows HSS to cut faster than
high carbon steel, hence the name high-speed steel.

Tungsten carbide has been applied in numerous important industries including aerospace,
oil and gas, automotive, semiconductor and marine as mining and cutting tools, mould
and die, wear parts, etc., which also has a promising future particularly due to
enabling to resist high temperature and are extremely hard.

In conclusion, the comparison of high speed steel and tungsten carbide are obvious. You
must choose the right one according to your requirement.

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How to choose tungsten carbide round saw blade?

Tungsten carbide round saw blade is a kind of round saw blade made of tungsten carbide. The main material composition is 65Mn,50Mn2V,SK5,SKS51 and 75Cr1 etc.

tungsten-carbide-round-saw-blade

The quality of tungsten carbide round saw blade depends on carbide tips material and manufacturing process. The steel substrate material is required to remain unchanged under high speed rotary cutting operation,high impact force and frictional heating condition. A reliable supplier of tungsten carbide round saw blade adopt the reasonable manufacturing process to delivery good quality products.

In conclusion, you need to find a reliable supplier and give them the application and technical requests of tungsten carbide round saw blade. In this way, they can help you choose the quality tungsten carbide round saw blade for you.

The sintering process of tungsten carbide

What is the sintering process of tungsten carbide? Briefly speaking,
tungsten carbide powder is gathered and then heated to a certain
temperature in the sintering furnace; after that, keeping it for a
period of time; finally, the powder is cooled down to become the
desired tungsten carbide materials. This is the hole sintering process
of tungsten carbide.

sintering process of tungsten carbide

During the sintering process of tungsten carbide, the changes of materials
are as follows:

One change is that, with the increase of temperature in the initial stage,
the components of tungsten carbide powder are gradually boiled away. At
the same time, the components give carbon to the sintering parts to some
degree. The amount of increased carbon determined by the type and number
of components, it can also influenced by the sintering process of tungsten
carbide.

Another important change of materials can also be seen, in the sintering
process of tungsten carbide, oxide of the powder surface is reduced. If
the sintering process is occured in the vacuum environment, chemical reaction
between carbon and oxide will not be so strong. During the process, contact
stress between powder particles is also gradually decreased, which will leads to
the metal powders begin to recovery and recrystallize.

In conclusion, sintering process of tungsten carbide is the main method of
manufacturing technology of hard alloy. It is hard to controll and operate,
as you must guarantee the components of the desired tungsten carbide materials.

Tomb-sweeping Day: we have to work overtime

What is Tomb-sweeping day?
Tomb-sweeping day is a very important festival in china. At that day ,
people have one day holiday , and they always go home and sacrifice to
ancestor. But this year, we have to work overtime at Tomb-sweeping day
to do some order handing.

work overtime

Why people choose work overtime at Tomb-sweeping day?
In fact, work overtime is quite normal. On the one hand, for many young
people, work is very important and interesting. On the other hand, some
people are hard to get back home to sacrifice to ancestor at Tomb-sweeping
day, because their hometown may be far from their working and living place.

Why we choose work overtime at this Tomb-sweeping day?
At this Tomb-sweeping day, our business are pretty good. That is the main
reason for working overtime. By the way, we are the manufacturer of tungsten
carbide, we have been in this field for more than 12 years.

Are you working overtime at Tomb-sweeping day? What is your idea about
work overtime? If you do not need to work overtime at that day, just enjoy it!

Surface pretreatment techniques of thermal spraying

Surface pretreatment of thermal spraying is generally divided into three steps, surface prefinishing, surface cleaning and surface roughening.

Surface prefinishing

Firstly,surface prefinishing can make the surface of the workpiece suit for deposition; secendly, it is do good to overcome the shrinkage stress of coating. Doing some surface prefinishing can disperse the local stress of some parts and increase the shear strength of the coating.

The method always used is cutting round corner. Making coarse thread on the workpiece surface is also a commonly used method, especially in the process of spraying large workpiece. Thread turning is commonly used to increase the bonding area. We should pay attention to two questions when turning thread: not only screw thread section should be suitable for spraying, that is to say, rectangular section or semi – circular cross section are both not suitable for combination of coating and workpiece; but also the thread can not be too deep, otherwise, the coating will be too thick. Another way to prefinish the surface is called knurling.

Surface cleaning

Solvent cleaning, alkali washing and heating degreasing are always use for surface cleaning to remove the oil and impurity on the surface of workpiece. Commonly used cleaning agent: Gasoline, acetone, carbon tetrachloride and trichloroethylene. Alkali cleaning is commonly used for major repairing, alkali liquor usually prepared with sodium hydroxide and sodium carbonate, which is a relatively cheap way.

Roughening treatment

In order to facilitate the mechanical bonding of the coating, sand blasting is always used to form uniform and uneven surface. Abrasive used for sand blasting can be pure alumina, brown fused alumina and silica sand, etc. Pure alumina is of high hardness, low broken rate and good effect for sand blasting. Brown fused alumina is of midium price. Silica sand has high hardness and high broken rate. Particle size of the sand should be chosen according to the shape of the workpiece.

During the process of sand blasting operation, attention should be paid to blasting distance and angle. Distance is generally in the range of 100_300mm section while angle should be between 45°-70°. Strong sand blasting can not be used on thin walled workpiece and flexible workpiece. The resulting surface after sand blasting has higher activity, which is easy to be oxidized in the atmosphere. You need to do the thermal spray process after sand blasting assoon as possible.

cemented carbide alloy application in weapons

I have shown you the jewelry and watch band made by hard alloy. Today I will show you the application of tungsten carbide alloy in military weapons: armor-piercing bullets(hard corn bullet).

images images1 index

The reason of armor-piercing bullet could shot through the thick armored target is the head of the bullet. It is made of tungsten carbide alloy. But at early stage. It is made of casted iron mostly.

The early 1850’s the wrought iron was considered thick armor, but a Major Sir W. Palliser found a solution to it. He invented a method of hardening the head of the pointed cast-iron shot. This allowed the metal to cool slowly and the body of the shot to be made tough.

Then it is 1880s. Forged steel rounds with points hardened by water took the place of the cast-iron shot.. At first, these forged-steel rounds were made of ordinary carbon steel. But as the armor improved fast. It need new method to keep up with.

Time comes to 1890s. Cemented steel armor became more and more common. A steel contains chromium and nickel became the new material to make the hard corn bullet. A Russian admiral introduce a soft metal cap over the point of shell. This made the bullet increased the penetration by cushioning the impact and avoid the bullet be damaged.

Since then, the bullet made by more and more tough, high hardness and density material. And thanks to that. It made tungsten carbide more useful. And we will change the world we known by our courage and spirit of innovation.

Related links:

https://thermalspraypowder.wordpress.com/2015/04/13/how-to-choose-tungsten-carbide-round-saw-blade/

http://www.wococarbide.net/news/effects-of-ball-milling-time-on-the-microstructures-and-properties-of-tungsten-carbide.html

about thermal spray powder

When we talk about the cemented carbide alloy knowledge. Thermal Spray We will think that the Thermal spraying is an industrial coating process we normally see. It consists of a heat source (flame or other) and a coating material in a powder or wire form which is literally melted into tiny droplets and sprayed onto surfaces at high velocity. This “spray welding” process is also known by many names including Plasma Spray, HVOF, Arc Spray, Flame Spray, and Metalizing.

 Thermal sprayed coatings are typically applied to metal substrates, but can also be applied to some plastic substrates. Thermal sprayed coatings uniquely enhance and improve the performance of the component. You can visit http://www.wococarbide.net/ to see more product examples. 

Now we will talk about what made the thermal spray can bear the high temperature, why this material can be used in corrosive environment? 

We know carbon is a very common chemical element in the nature environment. The different structure and constitute can determine its hardness, heat conductivity and other behaviors. For instance: the graphite is one of the softness substances, it is also a excellent electrical conductor. But thermal insulator. If we made a material can use the carbon element nature, change the quantity and structure of it. We will made a new substance that can used for us. That is call alloy. Which can help us can fight the disadvantage of the nature. 

Now let’s go further, to continue our topic. 

In our production. We normally use a alloy called Cr3C2. It contains five chemical element: They were Carbon, Cobalt, Chrome, Nickle, and Fe. These different component mixed together by different ratio can made different grade product for welding work.

There is a list made a company called Chengdu Woco Carbide Industry CO.,ltd.

Grade and chemical compositions

Main composition grade Chemical compsitions(%)
C Co Cr Ni Fe O
Cr3C2/Ni/Cr JP25NC 8.5~11.0 / 62.2-70.9 19.0~21.0 <0.5 <0.5
  JP20NC 9.5~11.0 / 73.8~75.6 15.0~17.0 <0.5 <0.5
  JP10NC 11.0~13.0 / 83.0~85.1 7.0~9.0 <0.5 <0.5

 Main grades, particle size and physical properties:

Main composition Grade Particle size Physical properties
Manufacture  Particle shape Hall flow rates s/50g Apparent desity g/cm3
Cr3C2/Ni/Cr JP25NC –45/+15μm -325+800Mesh    Agglomeration sinter    spherical <40 >2.3
JP25NC-1 –53/+15μm -270+800 Mesh <40 >2.3
JP25NC-2 –38/+15μm -400+800 Mesh <40 >2.3
JP20NC –45/+15μm -325+800 Mesh <40 >2.3
JP10NC –45/+15μm -325+800 Mesh <40 >2.3

 So we can get a conclusion:Thermal Spray is versatile and is an effective alternative and Thermal sprayed coatings can be an effective alternative to several surface treatments including: nickel and chrome plating, nitride or heat treat processes, anodizing, and weld overlay. Their” thickness depending on the coating material.

Thermal sprayed coatings offer more versatility

Versatility in SUBSTRATE choice:

Substrates can be most metals including: aluminum, steel, stainless steel, copper and bronze

Some plastics

Versatility in COATING material choice:

tungsten carbides

stainless steels

ceramics, (chrome oxide, aluminum oxide, zirconia, titania)

nickel- chrome carbides

pure metals (aluminum, zinc, copper)

This broad choice of materials give you design flexibility to solve specific performance problems.

Related links:

https://thermalspraypowder.wordpress.com/2015/04/13/how-to-choose-tungsten-carbide-round-saw-blade/

http://www.wococarbide.net/news/effects-of-ball-milling-time-on-the-microstructures-and-properties-of-tungsten-carbide.html