The properties of tungsten carbide wear parts:
Strength - Tungsten carbide has very high strength for a material so hard and rigid. Compressive strength is higher than virtually all melted and cast or forged metals and alloys.
Rigidity - Tungsten carbide compositions range from two to three times as rigid as steel and four to six times as rigid as cast iron and brass. Young’s Modulus is up to 94,800,000 psi.
High resistance to deformation and deflection is very valuable in those many applications where a combination of minimum deflection and good ultimate strength merits first consideration. These include spindles for precision grinding and roll for strip or sheet metal.
Impact Resistant - For such a hard material with very high rigidity, the impact resistance is high. It is in the range of hardened tool steels of lower hardness and compressive strength.
Heat and oxidation resistance - Tungsten-base carbides perform well up to about 1000°F in oxidizing atmospheres and to 1500°F in non-oxidizing atmospheres
Low temperature resistance (cryogenic properties) - Tungsten carbide retains toughness and impact strength in the cryogenic temperature ranges. (-453°F)
Thermal Conductivity - Tungsten carbide is in the range of twice that of tool steel and carbon steel.
Electrical Conductivity - Tungsten carbide is in the same range as tool steel and carbon steel.
Specific Heat - Tungsten carbide ranges from about 50% to 70% as high as carbon steel.
Weight - The specific gravity of tungsten carbide is from 1-1/2 to 2 times that of carbon steel.
Hot Hardness - With temperature increase to 1400°F, tungsten carbide retains much of its room temperature hardness. At 1400°F, some grades equal the hardness of steels at room temperature.
Tolerances - Many surfaces of even complete parts can be used the way they come from the furnace, “as sintered”, such as mining or drilling compacts. In those parts requiring precision ground accuracy, such as stamping dies, close-tolerance performs are provided for grinding or EDM.
Methods of Fastening - Tungsten carbide can be fastened to other materials by any of three methods; brazing, epoxy cementing, or mechanical means. Tungsten carbide’s low thermal expansion rate must be carefully considered when performs are provided for grinding or EDM.
Coefficient of Friction - Tungsten carbide compositions exhibit low dry coefficient of friction values as compared to steels.
Galling - Tungsten carbide compositions have exceptional resistance to galling and welding at the surface.
Corrosion-Wear Resistance - Specific grades are available with corrosion resistance approaching that of noble metals. Conventional grades have sufficient resistance to corrosion-wear conditions for many applications.
Wear-Resistance - Tungsten carbide wears up to 100 times longer than steel in conditions including abrasion, erosion and galling. Wear resistance of tungsten carbide is better than that of wear-resistance tool steels.
Surface Finishes - Finish of an as-sintered part will be about 50 micro inches. Surface, cylindrical, or internal grinding with diamond wheel will produce 18 micro inches or better and can produce as low as 4 to 8 micro inches. Diamond lapping and honing can produce 2 micro inches and with polishing as low as ½ micro inches.
Dimensional Stability - Tungsten carbide undergoes no phase changes during heating and cooling and retains its stability indefinitely. No heat treating is required.
2013年5月22日星期三
Tungsten Carbide Wear Parts
Tungsten Carbide Wear Parts
Tungsten carbide is widely used in industry because of its extraordinary properties. Because of its wear resistance and hardness (9.8 Moe's scale), tungsten carbide is ideally suited for wear parts, other machine parts and dies which are subject to severe service conditions, such as high temperatures, corrosion and abrasion. In recent years, tungsten carbide has emerged as a superior alternative to steel in many industrial applications.
A large portion of the tungsten volume in cemented carbide is today used in wear part applications, where there is a wide range of products from the very small (such as balls for ball-point pens) to large and heavy products, such as punches, dies or hot rolls for rolling mills in the steel industry.
Most of this tungsten carbide wears parts and the mining tools are made of straight WC-Co hard metals without any addition of other carbides.
Fine and ultrafine grained WC hard metals have become more and more important today in the field of wear parts, tools for chinless forming and cutting tools for cast iron, non ferrous alloys and wood.
The first submicron hard metals were launched on the market in the late 1970s and, since this time, the micro-structures of such hard metals have become finer and finer. The main interest in hard metals with such finer grain sizes derives from the understanding that hardness and wear resistance increase with decreasing WC grain size.
Tungsten carbide is widely used in industry because of its extraordinary properties. Because of its wear resistance and hardness (9.8 Moe's scale), tungsten carbide is ideally suited for wear parts, other machine parts and dies which are subject to severe service conditions, such as high temperatures, corrosion and abrasion. In recent years, tungsten carbide has emerged as a superior alternative to steel in many industrial applications.
A large portion of the tungsten volume in cemented carbide is today used in wear part applications, where there is a wide range of products from the very small (such as balls for ball-point pens) to large and heavy products, such as punches, dies or hot rolls for rolling mills in the steel industry.
Most of this tungsten carbide wears parts and the mining tools are made of straight WC-Co hard metals without any addition of other carbides.
Fine and ultrafine grained WC hard metals have become more and more important today in the field of wear parts, tools for chinless forming and cutting tools for cast iron, non ferrous alloys and wood.
The first submicron hard metals were launched on the market in the late 1970s and, since this time, the micro-structures of such hard metals have become finer and finer. The main interest in hard metals with such finer grain sizes derives from the understanding that hardness and wear resistance increase with decreasing WC grain size.
Tungsten carbide
Tungsten carbide
Tungsten carbide is an inorganic chemical compound which contains equal numbers of tungsten and carbon atoms. It is sometimes colloquially referred to as simply "carbide." In its most basic form, it is a fine gray powder, but it can be pressed and formed into shapes for use in industrial machinery, tools, abrasives, as well as men's jewelry.
It is important to note that tungsten carbide is made in many different grades, which have different properties depending on what each will be used for. There are nearly two dozen different grades of carbide, but they are almost all variations of just a few parameters: grain size, hardness, and the degree to which a binder is used. Generally, the higher the percentage of the finished product that is composed of binding materials like nickel, the softer it will be and the more it will wear. The size of the original powder grains makes slightly less difference, but can affect the amount of shock that the product will be able to withstand.
Tungsten carbide is an inorganic chemical compound which contains equal numbers of tungsten and carbon atoms. It is sometimes colloquially referred to as simply "carbide." In its most basic form, it is a fine gray powder, but it can be pressed and formed into shapes for use in industrial machinery, tools, abrasives, as well as men's jewelry.
It is important to note that tungsten carbide is made in many different grades, which have different properties depending on what each will be used for. There are nearly two dozen different grades of carbide, but they are almost all variations of just a few parameters: grain size, hardness, and the degree to which a binder is used. Generally, the higher the percentage of the finished product that is composed of binding materials like nickel, the softer it will be and the more it will wear. The size of the original powder grains makes slightly less difference, but can affect the amount of shock that the product will be able to withstand.
Advantages of tungsten carbide snowplow blade
The advantages of tungsten carbide snowplow blade:
Carbide insert snow plow blades feature inserts of tungsten carbide. The wear and abrasion resistant carbide inserts wear longer than any other type of blade in applications requiring long runs and high speeds, such as plowing interstate highways and airports. They can outlast standard steel edges 20 to 1.
Tungsten carbide-tipped snowplow and motor grader blades feature permanent inserts of virgin tungsten carbide, the most durable material in the world. The inserts resist wear and abrasion like no other material to dramatically reduce the need for blade changes. Downtime is turned into work time. Carbide tipped blades are available for nearly any machine, even smaller plows such as Meyer and Western. Snowplow blades are FSE(flat square edge) Grader blades are FSB(flat single bevel) to fit grader moldboard.
Equipped with genuine tungsten carbide inserts, which are secured firmly to the blade with our superior brazing technique, these snowplow blades offer unparalleled fracture and wear resistance. In fact, our tungsten carbide-edged snowplow blades are field and proven to have a life span 20 times greater than competitive all-steel blades, which can stand up against the ravages of winter, snow-packed roads, performing optimally in these conditions.
Carbide insert snow plow blades feature inserts of tungsten carbide. The wear and abrasion resistant carbide inserts wear longer than any other type of blade in applications requiring long runs and high speeds, such as plowing interstate highways and airports. They can outlast standard steel edges 20 to 1.
Tungsten carbide-tipped snowplow and motor grader blades feature permanent inserts of virgin tungsten carbide, the most durable material in the world. The inserts resist wear and abrasion like no other material to dramatically reduce the need for blade changes. Downtime is turned into work time. Carbide tipped blades are available for nearly any machine, even smaller plows such as Meyer and Western. Snowplow blades are FSE(flat square edge) Grader blades are FSB(flat single bevel) to fit grader moldboard.
Equipped with genuine tungsten carbide inserts, which are secured firmly to the blade with our superior brazing technique, these snowplow blades offer unparalleled fracture and wear resistance. In fact, our tungsten carbide-edged snowplow blades are field and proven to have a life span 20 times greater than competitive all-steel blades, which can stand up against the ravages of winter, snow-packed roads, performing optimally in these conditions.
Tungsten Carbide Snowplow Blade
Tungsten Carbide Snowplow Blade
About tungsten carbide:
Tungsten carbide is a very hard material produced from powder metal, it is normally referred to as hard metal in Europe. It’s combine the followings: hardness, good wear resistance of carbide phase, sufficient mechanical property, shock resistance of metal binging phase and it has been widely used in many aspects.
Tungsten carbide in its pure form is second only to diamond in hardness. It is alloyed with titanium, tantalum, and cobalt. All this in combination provides a material that resists impact and provides extraordinary wear resistance.
What is tungsten carbide snowplow blade?
Carbide product is available in two different forms to increase the performance for most of the wear products we offer. Carbide inserted cutting edges are primarily used on the snowplow and grader cutting edges. Carbide embedded wear edges are used in the loader, scraper, dozer and motor grader application.
We produces tungsten carbide inserts for snow plow blades in various dimensions, snow plow blades is used to cleaning the snow on road. All of these carbide inserts are made from the virgin raw materials and HIP/sintered, be of very high quality and excellent performances. However, the price is very competitive.
Carbide inserted-virgin tungsten carbide inserts are placed into milled grooves along the bottom wear surface of the edge giving it unmatched wear resistant properties and making this blade ideal for high speed highway or airport runway plowing.
About tungsten carbide:
Tungsten carbide is a very hard material produced from powder metal, it is normally referred to as hard metal in Europe. It’s combine the followings: hardness, good wear resistance of carbide phase, sufficient mechanical property, shock resistance of metal binging phase and it has been widely used in many aspects.
Tungsten carbide in its pure form is second only to diamond in hardness. It is alloyed with titanium, tantalum, and cobalt. All this in combination provides a material that resists impact and provides extraordinary wear resistance.
What is tungsten carbide snowplow blade?
Carbide product is available in two different forms to increase the performance for most of the wear products we offer. Carbide inserted cutting edges are primarily used on the snowplow and grader cutting edges. Carbide embedded wear edges are used in the loader, scraper, dozer and motor grader application.
We produces tungsten carbide inserts for snow plow blades in various dimensions, snow plow blades is used to cleaning the snow on road. All of these carbide inserts are made from the virgin raw materials and HIP/sintered, be of very high quality and excellent performances. However, the price is very competitive.
Carbide inserted-virgin tungsten carbide inserts are placed into milled grooves along the bottom wear surface of the edge giving it unmatched wear resistant properties and making this blade ideal for high speed highway or airport runway plowing.
Tungsten Carbide Seals
Tungsten Carbide Seals
Tungsten carbide is commonly used in mechanical seals, which is extremely tough and stiff and has very good abrasion resistance. Two common metal binders, cobalt and nickel, are used. Typically 6% binder materials are used in mechanical seals, although a wide range is available. Nickel-bonded tungsten carbides are more prevalent in the wastewater pump market due to their improved corrosion resistance compared with cobalt bound materials。
Seal face components made from solid silicon carbide are particularly well suited to abrasive and corrosive applications and can handle a wide range of temperature extremes. These components are excellent thermal conductors and can be specified where high strength and stiffness are required. Reaction bonded Silicone Carbide is also satisfactory for sealing faces, while it has excellent wear characteristics.
Tungsten carbide is commonly used in mechanical seals, which is extremely tough and stiff and has very good abrasion resistance. Two common metal binders, cobalt and nickel, are used. Typically 6% binder materials are used in mechanical seals, although a wide range is available. Nickel-bonded tungsten carbides are more prevalent in the wastewater pump market due to their improved corrosion resistance compared with cobalt bound materials。
Seal face components made from solid silicon carbide are particularly well suited to abrasive and corrosive applications and can handle a wide range of temperature extremes. These components are excellent thermal conductors and can be specified where high strength and stiffness are required. Reaction bonded Silicone Carbide is also satisfactory for sealing faces, while it has excellent wear characteristics.
Tungsten Carbide Sleeve
Product Description
1. Used for water pump, oil pump and other pumps, especially used for high pressure or corrosion resistance pumps.
2. Has a good wear resistance
3. Keeping operation precision, prolong the lifetime of rolling axletree.
4. Good materials, perfect performance, high machining accuracy, have high reputation all over the world.
5. Various types and grades, supplied as required
1. Used for water pump, oil pump and other pumps, especially used for high pressure or corrosion resistance pumps.
2. Has a good wear resistance
3. Keeping operation precision, prolong the lifetime of rolling axletree.
4. Good materials, perfect performance, high machining accuracy, have high reputation all over the world.
5. Various types and grades, supplied as required
Solid Carbide Cutting Tools
Solid Carbide Cutting Tools
The cutting edge hardness of carbide ranges from 77 to 81 HRC. Solid carbide cutting tools, such as drills and end mills, are thermally stable and offer high resistance to abrasive wear. Carbide is brittle, however, and rough handling, misuse, or misalignment can lead to broken tools and/or poor tool life. Rigid setups and accurate spindles are necessary for peak performance. Carbide is more expensive then steel so larger solid carbide tools tend to be more expensive.
The cutting edge hardness of carbide ranges from 77 to 81 HRC. Solid carbide cutting tools, such as drills and end mills, are thermally stable and offer high resistance to abrasive wear. Carbide is brittle, however, and rough handling, misuse, or misalignment can lead to broken tools and/or poor tool life. Rigid setups and accurate spindles are necessary for peak performance. Carbide is more expensive then steel so larger solid carbide tools tend to be more expensive.
2013年5月7日星期二
Tungsten Carbide Physical properties
Tungsten carbide has a high melting point at 2,870 °C (5,200 °F), a boiling point of 6,000 °C (10,830 °F) when under a pressure equivalent to 760mm of Hg,[9] a thermal conductivity of 84.02, and a coefficient of thermal expansion of 5.8 µm.
Tungsten carbide is extremely hard, ranking ~9 on Mohs scale, and with a Vickers number of 1700–2400. It has a Young's modulus of approximately 550 GPa, a bulk modulus of 439 GPa, and a shear modulus of 270 GPa. It has a very high yield stress at 6800 MPa, but a comparatively low ultimate tensile strength of just 35 MPa.
The speed of a longitudinal wave (the speed of sound) through a thin rod of tungsten carbide is 6220 m/s.
With a low electrical resistivity of, tungsten carbide's resistivity is comparable with that of some metals.
WC is readily wetted by both molten nickel and cobalt. Investigation of the phase diagram of the W-C-Co system shows that WC and Co form a pseudo binary eutectic. The phase diagram also shows that there are so-called η-carbides with composition (W,Co)6C that can be formed and the fact that these phases are brittle is the reason why control of the carbon content in WC-Co hard metals is important.
Tungsten Carbide Structure
There are two forms of WC, a hexagonal form, α-WC (hP2, space group P6m2, No. 187),and a cubic high-temperature form, β-WC, which has the rock salt structure.The hexagonal form can be visualized as made up of hexagonally close packed layers of metal atoms with layers lying directly over one another, with carbon atoms filling half the interstices giving both tungsten and carbon a regular trigonal prismatic, 6 coordination. From the unit cell dimensions the following bond lengths can be determined; the distance between the tungsten atoms in a hexagonally packed layer is 291 pm, the shortest distance between tungsten atoms in adjoining layers is 284 pm, and the tungsten carbon bond length is 220 pm. The tungsten-carbon bond length is therefore comparable to the single bond in W(CH3)6 (218 pm) in which there is strongly distorted trigonal prismatic coordination of tungsten.
Molecular tungsten carbide has been investigated and this gas phase species has a bond length of 171 pm for 184W12C.
Molecular tungsten carbide has been investigated and this gas phase species has a bond length of 171 pm for 184W12C.
Tungsten Carbide Chemical properties
Tungsten carbide have two well characterized compounds of tungsten and carbon, WC and tungsten semicarbide, W2C. Both compounds may be present in coatings and the proportions can depend on the coating method.
At high temperatures WC decomposes to tungsten and carbon and this can occur during high-temperature thermal spray, e.g., in high velocity oxygen fuel (HVOF) and high energy plasma (HEP) methods.
Oxidation of WC starts at 500–600 °C. It is resistant to acids and is only attacked by hydrofluoric acid/nitric acid (HF/HNO3) mixtures above room temperature.[3] It reacts with fluorine gas at room temperature and chlorine above 400 °C (752 °F) and is unreactive to dry H2 up to its melting point. WC dissolves readily in diluted hydrogen peroxide.
At high temperatures WC decomposes to tungsten and carbon and this can occur during high-temperature thermal spray, e.g., in high velocity oxygen fuel (HVOF) and high energy plasma (HEP) methods.
Oxidation of WC starts at 500–600 °C. It is resistant to acids and is only attacked by hydrofluoric acid/nitric acid (HF/HNO3) mixtures above room temperature.[3] It reacts with fluorine gas at room temperature and chlorine above 400 °C (752 °F) and is unreactive to dry H2 up to its melting point. WC dissolves readily in diluted hydrogen peroxide.
New Era of Tungsten Carbide as Cutting Material
In recent years,
all kinds of new cutting tools that were launched by the manufacturer of cutters
have caught people’s attention in hardware machine tool exhibition. In order to
reach the goal and lay a foundation for long-term development of “twelfth
five-year”, importance of hardware industries should be attached to product
structure adjustment, diamond cutter innovation and industry restructuring.
Experts believed
that tungsten carbide used as cutting materials would create a new era. Compared
with the high speed steel, tungsten carbide performs better properties and owns
higher cutting efficiency. It is an important guarantee to realize efficient
process of modern cutting technology when it combined with super hard
materials. Now, the proportion of tungsten carbide cutting tool in our country
reaches 40%, far below the level of developed country, which has seriously
restricted the improvement of cutter products? Better cutting materials, more
solid foundation for the adjustment of cutting tools. Without better cutting
materials, the reform of increasing proportion of cutting material would not be
achieved. Therefore, tungsten carbide as cutting material would be catalyst for
the reformation of cutting industries.
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