SPECIFICATIONS:

The name of the knife: NOSFERATU collector's exclusive folding knife, handmade by the master of the ANDROSHCHUK KNIVES studio, buy to order in Ukraine (CPM® REX 121™ steel covered with weather-resistant Damascus 67 HRC)
Knife type: Folding blade
Brand: Studio of exclusive handmade knives ANDROSHCHUK KNIVES 

Steel brand: Blade - steel of the CPM REX 121 brand in a coating of weather-resistant Damascus - a tool powder fast-cutting alloy of the American company Crucible Industries LLC
Steel sheet: One-piece, folds into a handle
Blade Sharpening Angle: 36 Degree Pointed
Descents: Direct
Pitch: 0.25mm
Blade hardness: 67 HRC
Total length: 260 mm
Blade length: 110mm
Blade width: 32 mm
Blade thickness: 0.4 mm
Length of the handle: 150 mm
Handle thickness: 17mm
Total weight: 273 grams
Grinding of the blade: Finish - mirror polished, false blade - machine polished satin
Bolster and back material: Stainless steel
Handle material: VT20 titanium frame, pins, spacer, timaskus clip (titanium damascus). Linings - carbon. In the axial unit there are ceramic bearings, the detector ball is ceramic, hardened nuts made of N690 steel, in the lock there is a hardened nut with a ceramic detent ball.
Handle color: Grey-turquoise-titanium
Handle Impregnation: None
Handle cover: None
Hole for a shoelace (for a lanyard): None
Temlyak: Absent
Vagina: Yes

Model: NOSFERATU collector's exclusive folding knife, handmade by the master of the ANDROSHCHUK KNIVES studio, buy to order in Ukraine (CPM® REX 121™ steel covered with weather-resistant Damascus 67 HRC)
Model number: 057
Country of birth: Ukraine
Craftsman: Master Grigory Androshchuk (Androshchuk Knives), m.Vinnytsia, Ukraine Studio of exclusive handmade knives ANDROSHCHUK KNIVES
Best use: Multi-purpose: hunting, fishing, cutting, slicing, etc
Knife condition: new
The price is indicated with the sheath.

A sharpened knife is not a cold weapon.

Our knives are very sharp, so open and use very carefully. We are not responsible for injuries related to the use of our knives.
Our products are intended for legal use only by responsible buyers. We will not sell our products to anyone under the age of 18.

Availability changes regularly, upon confirmation of your order, we will inform you about the availability or when the product will be ready. The product may differ slightly from the one shown in the photo.

Crucible CPM® Rex® 121® Powder Steel

CPM® REX® 121 (Crucible Industries LLC) is a high-vanadium-cobalt tool steel designed to achieve the high wear resistance, hardness and red-hardness characteristics of high-speed steel. Its excellent red resistance ( red resistance is a characteristic of the heat resistance of steel, indicating the ability of steel to retain high hardness and wear resistance obtained as a result of heat treatment when heated to red-hot temperatures ) provides a higher cutting speed compared to other high-speed cutters. Excellent wear resistance (due to high vanadium content) helps maintain a sharp edge at higher cutting speeds.

Powder high-speed steel was developed in the late 60s of the last century in Sweden. The powder metallurgy method makes it possible to introduce more alloying elements into steel without reducing strength and workability.

Powdered steel, unlike ordinary steel, is fed in molten form through a special nozzle through a stream of liquid nitrogen. The steel quickly hardens into small particles. The result is a powder with a uniform arrangement of carbides (the place where carbides accumulate is the place where cracks nucleate). Carbides perform the same function in steel as cobblestones on the street: they (carbides) are harder than the steel surrounding them and help increase its wear resistance.

The resulting powder is sifted and placed in a steel container, in which a vacuum is created. Next, the contents of the container are sintered at high temperature and pressure, thereby achieving uniformity of the material. This process is called hot isostatic pressing. After this, the steel is pressure treated. The result is a high-speed steel with very small carbide particles evenly distributed in the steel base. The resulting steel can be rolled in the traditional way, just like commercial steel grades, resulting in increased strength.

Differences in the wear resistance of different grades of powder steel are explained by the presence of different carbides in their composition in different proportions and with different uniformity of distribution throughout the entire volume of steel. Of two steels that have approximately the same hardness, the one that contains more carbides or is harder will be more wear-resistant.

CPM REX 121 bridges the gap between high-alloy tool steels and carbide materials ( tungsten carbide, which is second only to diamond in hardness ) . Can be used in cutting tools where high cutting speeds require higher heat resistance but carbide tools are too brittle, or in high wear resistant tools (dies) where carbide tools are also too brittle.

CPM Rex 121 was developed in 1998. In terms of hardness, this is truly a champion, capable of achieving a hardness of 70-72 HRC. For information, officially the Rockwell C scale has a maximum value of 70 HRC.

Also extremely high wear resistance. Difficult to grind and therefore difficult to sharpen. Sharpening this alloy can be a nightmare even at 68HRC, and it will be exponentially harder at higher hardnesses. With so many alloying elements, steel has a lot of carbides, and some of them are not very small. Steel works better with coarse sharpening (the photo below shows a comparison of the microstructures of popular steel grades and the microstructure of CPM Rex 121).

There are many hard steels in the world, but according to renowned knife maker Gary Creely, the REX 121 takes it to the next level. “The steel has a low Rockwell hardness of 40 even after annealing, and after heat treatment it is close to 70 HRC.” The steel is described as Crucible's answer to rival Carpenter CTS steel, Maxamet Micro-Melt Alloy. Although they are very similar in chemical composition, REX 121 contains 1% more carbon and 3% more vanadium. The practical result of this hardness value is unprecedented edge retention. Knives made from REX 121 will significantly outperform even other high-quality steels such as M4 and S35VN. 

Steel is not highly impact resistant and can break if abused, but Creely believes that excellent edge retention is more useful than high strength in the small knives we carry every day. “This steel is best suited for smaller knives. If REX 121 finds its way to a larger blade, the chances of it being misused will increase dramatically."

The disadvantage of REX 121 is that it is so hard that it can damage conventional abrasives. “In short, you need to use diamond abrasives to sharpen this type of steel,” notes Creeley. “If you choose your favorite Japanese water stone, there is a good chance that the steel will cut your water stone harder than the stone will sharpen the steel.”

Steel composition:

C 3.4% - the carbon content in the alloy is 3.4%. Carbon is the most important element in steel; it increases its strength and gives the metal good hardness.

Cr 4.0% - chromium content in the alloy is 4.0%. Chrome is a grayish-white, shiny, hard metal. Chromium affects the ability of steel to harden, gives the alloy anti-corrosion properties and increases its wear resistance. Contained in stainless steel of any grade.

Mo 5.0% - the molybdenum content in the alloy is 5.0%. Molybdenum is a silvery-white metal. Molybdenum is a hard-melting element; it prevents the blade from becoming brittle and brittle, giving it the necessary rigidity and making it quite resistant to high temperatures.

V 9.5% - the vanadium content in the alloy is 9.5%. Vanadium is a greyish-white shiny metal with great hardness. It is responsible for elasticity and enhances the properties of chromium, making the metal inert to aggressive chemical environments.

W 10.0%  C tungsten content in the alloy is 10.0%. Tungsten is a light gray metal. The most refractory metal, has a melting point tmelt = 3380 °C. Used to create alloys with high strength. Tungsten is used as one of the main components or alloying elements in the production of high-speed steels.

Co 9.0%   - the cobalt content in the alloy is 9.0%. Cobalt is a silvery-white, slightly yellowish metal with a pinkish or bluish tint. Increases heat resistance, improves mechanical properties. Processing tools are created from alloys using cobalt: drills, cutters, etc. etc.

S 0.03 - 0.12% - sulfur content in the alloy - 0.03 - 0.12%. Sulfur, like phosphorus, is a harmful technological impurity in steels and alloys. An increase in sulfur content significantly reduces the mechanical and physicochemical properties of steels, in particular, ductility, impact strength, abrasion resistance and corrosion resistance. The limits for sulfur content as a technological impurity are 0.035...0.06%. Due to the extremely fine and uniform microstructure of CPM (Crucible Particle Metallurgy's proprietary powder metallurgy process), sulfur can be added if desired to improve machinability. Higher sulfur content benefits the tool manufacturer by making it easier to manufacture and the tool user by making re-sharpening easier. The CPM process ensures that additional sulfur does not have a detrimental effect on tool strength.

It is worth remembering that when using a knife for its intended purpose and with careful handling, the knife will serve you for a very, very long time.

CARBON - KNIFE HANDLES FROM THIS PREMIUM MATERIAL

One of the most prestigious and expensive materials for knife handles, in addition to titanium and expensive woods, is a type of carbon fiber, the so-called "carbon". The material is valued for its exceptional lightness, strength and aesthetic beauty.

Carbon (from the English carbon - carbon) is a polymer material with a composite composition, made from interlaced carbon fiber filaments (carbon fibers). These threads are made using epoxy resins. Average material density from 1450 kg/m³ to 2000 kg/m³. The main difference between carbon fiber and other polymers used in the manufacture of knives is its very low weight. It is the weight combined with exceptional strength that gives carbon an advantage over other handle materials: G10 polymer, Micarta, FRN plastic, etc. At the same time, carbon fiber surpasses structural steels in terms of specific strength characteristics. The main qualities of carbon are: high tensile strength, resistance to high temperatures, aggressive environments, slight expansion when heated, high electrical conductivity. Another important feature of carbon fiber is its natural black color obtained during production, which gives it a noble and elite appearance.

The basis of the material is carbon fiber threads, with an average thickness of 0.005-0.010 mm in diameter. Carbon fibers are made through a complex heat treatment process. The main fiber (polyacryl, viscose) is initially oxidized in air at 250°C for 24 hours. As a result of oxidation, ladder structures are formed (polymers whose macromolecules are crosslinked in pairs by regular chemical bonds). Then carbonization takes place (the process of enriching the filaments with carbon), which takes place when the fiber is heated in nitrogen or argon at temperatures from 800 to 1500 °C. As a result of carbonization, graphite-like structures (allotropic modifications of carbon) are formed. The heat treatment process ends with graphitization (the formation of graphite in materials in which carbon is contained in a dissolved state or in the form of carbides), it takes place at a temperature of 1600-3000 ° C, in an inert environment. As a result of graphitization, the amount of carbon in the fiber is brought to 99%. In addition to conventional organic fibers, special fibers from phenolic resins, lignin, coal and petroleum pitches can be used to produce carbon filaments.

Carbon fabrics, in turn, are obtained by weaving threads or ribbons. In the production of these threads, carbon roving is taken as the basis - a bundle of thin continuous carbon fiber filaments with a thickness of 3 microns, formed by carbon atoms. After interlacing, they form a carbon fiber frame. The amount of carbon fiber in a thread is estimated by the number "K" - the number of thousands of elementary carbon fibers. The thinnest and most expensive carbon fiber is 1K, the most common carbon fiber is 3K, there are also carbon fiber threads with K \u003d 6, 12, 24, 48. Fabric made from threads can have a variety of weaving patterns (herringbone, matting, twill weaving, etc.). To give even greater strength to the fabric, carbon threads are laid in layers, each time changing the angle of the direction of weaving. The layers are held together with epoxy resins. This structure of carbon makes it possible to reinforce the fiber with additional elements that strengthen its structure and give it different colors and surface textures. These materials can be various threads, sequins, polymeric materials of different colors.

The main methods for manufacturing carbon plates are:

Pressing, in which the fabric is lined in a form, previously lubricated with a so-called release agent, designed to reduce the adhesion of surfaces to each other. They can be soap, wax, etc. The fabric is then impregnated with resin and the excess is removed under vacuum (vacuum molding) or under pressure. After polymerization of the resin, the product takes on a finished look.

Vacuum infusion allows you to create a laminated bag by superimposing layers of tissue on top of each other and vacuum is applied under the layers. Then, a binder is fed through the valve and, under the action of vacuum, it fills the voids and impregnates the carbon fabric.

Vacuum forming is the bonding of layers at high temperatures and then exposure to vacuum to form the volume of the product. This method is one of the cheapest.

Winding method, which consists in winding the impregnated roving on a pre-prepared form. After winding the required number of layers, the mold with the wound fabric is placed in a heating oven and polymerized.

The SMC/BMC method consists of placing the fabric in a mold heated to operating temperature. The mold closes, as a result of which, under pressure, the material spreads into the mold cavity and hardens. At the end of the cycle, the product is removed from the molds us, and its final machining and coloring is carried out.

Carbon fiber is used in various fields. In particular, in aircraft and rocket building, in the production of body parts for cars and motorcycles, household appliances and high-tech research instruments. And for about 20 years, carbon fiber has been widely used in the manufacture of knife handles in the middle and premium segments. At the same time, on folding knives, carbon can be both in the form of overlays on steel liners, and in the form of the only material of the handle, fixed with screws through the bonks.

The carbon used for the manufacture of knives, in addition to its main strength characteristics, must also have a fairly attractive appearance. It is this factor that increases its cost, complicating the production technology and requiring the highest quality raw materials. For sizing the layers, the most expensive and high-quality resins are used, and more expensive equipment, in particular chemical reactors (autoclaves). In addition, the carbon fiber is sandblasted to improve hand grip, which also increases production costs. It must also be remembered that working with carbon requires mandatory respiratory protection and special rooms with good ventilation, and this also leads to an increase in price.

The color palette and texture of carbon used on knives can be varied. Among the varieties of carbon are used:

Mosaic carbon, which can be both plain and multi-colored. Such carbon is used for radius spacers on knives with complex multi-section handles. Several dyeing technologies can be used in this carbon.

Marble carbon is a chaotic interlacing of carbon fibers, each of which reflects light differently, which makes it possible to shine from different viewing angles.

Carbon Lightning Strike ("lightning strike") with a copper thread in the form of a grid woven into carbon fabric throughout its volume. Outwardly similar to that used in the fuselages of American aircraft to protect against lightning strikes. This is a thin carbon, 3.2 mm thick twill weave. It has a deep and bright pattern.

Like any expensive, and at the same time difficult to manufacture material, carbon has a number of disadvantages. In the production of carbon fiber plastics, it is necessary to strictly adhere to the technological parameters, in violation of which the strength properties of products are sharply reduced. To control the quality of products, ultrasonic flaw detection, X-ray and optical holography, as well as acoustic testing can be used. Without them, the manufacturer works “by touch” and may not notice hidden defects. Another serious drawback of CFRPs is their low impact resistance. It is also necessary to remember that carbon fades over time and can significantly lose its main advantage - an attractive appearance. However, despite these shortcomings, carbon is rightfully the premium material for the best knives.

High-quality and original steel inserts are a wonderful decoration of exclusive and unique knives of the Studio of exclusive handmade knives ANDROSHCHUK KNIVES (Ukraine), which offers to order and buy online store https://knife.net.ua