Black material alloy steel, stainless steel, tool steel and cast iron is the main application field of molybdenum, which determines the demand for production of molybdenum, molybdenum role in the above steel are as follows:
1. Decreasing the cooling rate to an appropriate value to obtain a hard martensite structure, thereby improving the strength, hardness and toughness of the large-section member;
2. Reduce temper brittleness;
3. Anti-hydrogen embrittlement;
4. Stress cracking caused by sulfide resistance;
5. Improve high temperature strength;
6. Improve the corrosion resistance of stainless steel, especially against chloride pitting;
7. Improve the welding performance of high strength low alloy steel.
Non-ferrous alloys Molybdenum is an important additive in most superalloys and many nickel -based and titanium -based alloys. At high temperatures, molybdenum can effectively accelerate solid strengthening, prevent pitting of chlorides, and improve corrosion resistance in reducing liquids.
Molybdenum-based alloys Molybdenum and molybdenum alloys are widely used because of their many properties, such as high strength (2000 ° C), low thermal expansion coefficient, excellent thermal and electrical conductivity, and melting glass, molten salt and molten metal. High corrosion resistance and improved wear resistance of thin coatings.
Molybdenum Steel Molybdenum is a special steel alloying element. Molybdenum not only brings many of its excellent properties into steel, but it is also easily added to molten metals. Adding molybdenum oxide, ferromolybdenum or molybdenum-containing scrap to the steel can greatly reduce the smelting loss.
Carburized steel molybdenum (0.15% to 0.30%) is used in carburized steel to improve the hardenability of the low carbon portion of the core and to increase the toughness of the high carbon portion. It is especially effective for parts with large cross sections, such as gears. Molybdenum is not oxidized during carburizing, and as an effective hardener, molybdenum does not cause cracks and flaking on the surface.
High temperature steel has a large molybdenum atom relative to other alloying elements. Therefore, it is a very effective strengthening agent that increases the creep strength of steel to a level that can be used at around 600 °C. Its size effectively prevents the migration of arsenic atoms to the grain boundaries, thereby preventing temper brittleness. Hydrogen diffusion is also prevented and the degree of hydrogen induced cracking is reduced to a minimum. [next]
The earliest type of high temperature steel to which these characteristics of molybdenum were applied was 0.50% C-Mo steel. It has been replaced by a Cr-Mo series steel containing 0.50% to 2.0% molybdenum. 2.25Cr-1.0%Mo steel is a main alloy steel widely used in equipment of petroleum refineries, power plants and petrochemical plants.
High-strength low-alloy (HSLA) steel molybdenum plays an important role in the development of low-carbon microalloyed HSLA steel. The addition of 0.1% to 0.3% of molybdenum refines the acicular ferrite grain structure and enhances the precipitation hardening effect obtained from other alloying elements. Without the intensive heat treatment, HSLA steel can achieve a high yield strength of 450 to 600 MPa (65 to 85 ksi). Due to the plastic brittle transition temperature as low as -60 °C, these materials are used in large quantities to build pipelines to distant Arctic oil and gas fields. Thinner-sized molybdenum-containing HSLA steels have good formability, and their high strength/weight ratio makes them ideal automotive component materials.
The continuous exploration of new sources of petroleum in petroleum industry pipes has made the development and development of deep oil layers necessary, and the deep oil layers are often contaminated by corrosive hydrogen disulfide, carbon dioxide and high chloride brine, thus containing 0.15% to 0.25% molybdenum. The AISI 4100 series Cr-Mo steel is widely used. The improved 4140 series containing 0.4% to 0.6% molybdenum is the most resistant low alloy steel for sulfide stress cracking (SCC) and can be used in sour wells. As drilling depths deepen and conditions of use deteriorate, the use of high-moisture stainless steel and nickel-based alloys such as alloy C-22 (13% Mo) and alloy C-276 (16% Mo) will continue to increase.
Stainless steel has corrosion resistance due to the fact that chromium can naturally form a thin protective film on the steel surface. Molybdenum makes this passivation film stronger and allows it to be rapidly regenerated when the passivation film is destroyed by chloride. An increase in the molybdenum content increases the corrosion resistance of the pitting and cracks on the stainless steel.
Model 316 (2% to 3% Mo) is the most widely used molybdenum-containing stainless steel. It is designated as a tank, pipe and heat exchanger material for food processing and processing and pharmaceutical production. Increased molybdenum content enhances resistance to chlorides in the air, so Type 316 can be used as a material of choice for offshore and coastal buildings. Model 316 is used to cover the Canary Wharf building in London and the tallest building in the world - the outer layer of the Petronas Tower in Kuala Lumpur, Malaysia.
Duplex stainless steel (3% to 4% Mo) has high strength and excellent resistance to chloride stress corrosion cracking. Multipurpose stainless steel, originally used as a transfer tube in the oil and gas industry, is now used more in the chemical processing and petrochemical industries and as a digester for the pulp and paper industry.
The most corrosion resistant stainless steel contains 6% to 7.3% Mo. Such alloy steels are used as power plant condensers, subsea pipelines, and key components of nuclear power plants, such as industrial water pipelines. In 1996, in a thermal power plant in South Korea, stainless steel containing 6% of Mo was used for the absorption tower containing more than 20 flue gas desulfurization scrubbers. [next]
Pitting/interstitial corrosion The passive chromium oxide layer is very sensitive near the grain boundaries and near non-metallic inclusions, forming microbatteries and rapidly producing pitting. Anoxic areas, such as under gaskets or lap joints, are very sensitive to similar corrosion and are often referred to as interstitial corrosion.
Molybdenum is the most effective and cheapest alloying element to prevent pitting corrosion and interstitial corrosion. Stainless steel in corrosive media exposed to high temperatures, especially in corrosive media containing chlorides and sulfides, where stress corrosion cracking (SCC) occurs if additional or residual tensile stresses are present. Increasing the molybdenum content is one of the most effective ways to improve the stress corrosion cracking of steel.
In scrubbers, pulp and paper, and chemical processing equipment in power plants operating in extremely harsh operating environments, alloys with very high molybdenum content are required. Alloys containing very high molybdenum include typical alloys containing 6% to 8% Mo and nickel-based alloys containing 10% to 16% Mo.
One of the earliest applications of tool steel and high-speed steel molybdenum is the use of tungsten as a substitute for tool steel and high-speed steel, which is effective and low-cost. The atomic weight of molybdenum is about half that of tungsten, so 1% of molybdenum is roughly equivalent to 2% of tungsten. Since these high-alloy steels are used for machining, cutting, and forming metal parts, they must have high hardness, high strength, and high toughness over a wide temperature range.
Cast Iron <br> Molybdenum increases the strength and hardness of cast iron by lowering the pearlite transformation temperature. It also increases the strength and creep resistance at high temperatures. High chromium cast iron containing 2% to 3% molybdenum exhibits greater impact toughness than high chromium cast iron without molybdenum and is ideal for use in harsh abrasive conditions, such as mining, milling, crushing, etc. Applications. These cast irons have acceptable performance, which eliminates the need for costly heat treatments, making them an inexpensive alternative to other abrasive materials. Reducing the austenite forming elements such as nickel and manganese also reduces the potential for premature failure of low temperature austenite retention.
The application of high Si-Mo plastic iron with a silicon content of 4% and a molybdenum content of 1% has attracted more and more interest. Their good strength at 600 ° C makes them an effective and inexpensive alternative to iron and steel with high alloy content in high temperature applications, such as in turbocharger housings, engine exhaust manifolds and furnace components. In the application. The austenitic quenched ductile iron has a unique microstructure with a strength exceeding 1000 MPa (145 ksi) and good impact toughness. Their specificity makes them ideal for special applications such as power transmission, ship engines and large gears and crankshafts required for large mining equipment. [next]
The most important limitation of powder metallurgy to improve the alloy content of high alloy ingot materials such as high speed steel is the tendency to segregate during slow cooling. Powder metallurgy technology atomizes the molten steel into droplets, and the droplets are cooled extremely quickly, preventing internal segregation. The steel produced by the coagulation of these particles has a fairly uniform microstructure and has numerous advantages over comparable conventional brand steels. Many powder metallurgy (PM) high speed steels, stainless steels and nickel based alloys have been put on the market, and this technology foreshadows the possibility of producing a new generation of high alloy steels in the future.
In the superalloy industry, powder metallurgy (PM) technology produces key parts with high alloy content, such as gas turbine components. Mo/Cu and W/Cu heat sinks for heat treatment in microelectronic devices.
Lubricating molybdenum disulfide is the most common form of molybdenum, which is used directly as a lubricant after extraction and purification from ore. Since molybdenum disulfide is a layered structure, it is a very effective lubricant. These delaminations can slide against each other, allowing free flow on steel and other metal surfaces, even under heavy pressure, such as bearing surfaces. Since molybdenum disulfide is formed by geothermal action, it has chemical stability against hot pressing. A small amount of sulfur reacts with the iron and forms a sulfide layer which is compatible with the molybdenum sulfide and maintains a lubricating film. Molybdenum disulfide is inert to many chemicals and will perform its lubrication under vacuum, while graphite does not.
Molybdenum disulfide has many unique properties compared to other solid lubricants, including:
1. Molybdenum disulfide is different from graphite, its friction coefficient is low (0.03 ~ 0.06), not caused by adsorption film or gas, lubricity is inherent in itself;
2. Strong affinity with metals;
3. having a film forming structure;
4. Yield strength up to 3450 MPa (500 psi);
5. Stability in most solvents;
6. Excellent air performance in air at 350 ° C (under 1200 ° C inert or vacuum conditions)
The molybdenum compound and the water-soluble sulfur compound solution are mixed to have lubricity and corrosion inhibition properties in the cutting fluid and the metal forming material. Oil-soluble molybdenum sulfur compounds, such as phosphates and thio thiocarbamates, can avoid wear, oxidation and corrosion of the engine. Several lubricant manufacturers have produced these lubricant additives.
1. Decreasing the cooling rate to an appropriate value to obtain a hard martensite structure, thereby improving the strength, hardness and toughness of the large-section member;
2. Reduce temper brittleness;
3. Anti-hydrogen embrittlement;
4. Stress cracking caused by sulfide resistance;
5. Improve high temperature strength;
6. Improve the corrosion resistance of stainless steel, especially against chloride pitting;
7. Improve the welding performance of high strength low alloy steel.
Non-ferrous alloys Molybdenum is an important additive in most superalloys and many nickel -based and titanium -based alloys. At high temperatures, molybdenum can effectively accelerate solid strengthening, prevent pitting of chlorides, and improve corrosion resistance in reducing liquids.
Molybdenum-based alloys Molybdenum and molybdenum alloys are widely used because of their many properties, such as high strength (2000 ° C), low thermal expansion coefficient, excellent thermal and electrical conductivity, and melting glass, molten salt and molten metal. High corrosion resistance and improved wear resistance of thin coatings.
Molybdenum Steel Molybdenum is a special steel alloying element. Molybdenum not only brings many of its excellent properties into steel, but it is also easily added to molten metals. Adding molybdenum oxide, ferromolybdenum or molybdenum-containing scrap to the steel can greatly reduce the smelting loss.
Carburized steel molybdenum (0.15% to 0.30%) is used in carburized steel to improve the hardenability of the low carbon portion of the core and to increase the toughness of the high carbon portion. It is especially effective for parts with large cross sections, such as gears. Molybdenum is not oxidized during carburizing, and as an effective hardener, molybdenum does not cause cracks and flaking on the surface.
High temperature steel has a large molybdenum atom relative to other alloying elements. Therefore, it is a very effective strengthening agent that increases the creep strength of steel to a level that can be used at around 600 °C. Its size effectively prevents the migration of arsenic atoms to the grain boundaries, thereby preventing temper brittleness. Hydrogen diffusion is also prevented and the degree of hydrogen induced cracking is reduced to a minimum. [next]
The earliest type of high temperature steel to which these characteristics of molybdenum were applied was 0.50% C-Mo steel. It has been replaced by a Cr-Mo series steel containing 0.50% to 2.0% molybdenum. 2.25Cr-1.0%Mo steel is a main alloy steel widely used in equipment of petroleum refineries, power plants and petrochemical plants.
High-strength low-alloy (HSLA) steel molybdenum plays an important role in the development of low-carbon microalloyed HSLA steel. The addition of 0.1% to 0.3% of molybdenum refines the acicular ferrite grain structure and enhances the precipitation hardening effect obtained from other alloying elements. Without the intensive heat treatment, HSLA steel can achieve a high yield strength of 450 to 600 MPa (65 to 85 ksi). Due to the plastic brittle transition temperature as low as -60 °C, these materials are used in large quantities to build pipelines to distant Arctic oil and gas fields. Thinner-sized molybdenum-containing HSLA steels have good formability, and their high strength/weight ratio makes them ideal automotive component materials.
The continuous exploration of new sources of petroleum in petroleum industry pipes has made the development and development of deep oil layers necessary, and the deep oil layers are often contaminated by corrosive hydrogen disulfide, carbon dioxide and high chloride brine, thus containing 0.15% to 0.25% molybdenum. The AISI 4100 series Cr-Mo steel is widely used. The improved 4140 series containing 0.4% to 0.6% molybdenum is the most resistant low alloy steel for sulfide stress cracking (SCC) and can be used in sour wells. As drilling depths deepen and conditions of use deteriorate, the use of high-moisture stainless steel and nickel-based alloys such as alloy C-22 (13% Mo) and alloy C-276 (16% Mo) will continue to increase.
Stainless steel has corrosion resistance due to the fact that chromium can naturally form a thin protective film on the steel surface. Molybdenum makes this passivation film stronger and allows it to be rapidly regenerated when the passivation film is destroyed by chloride. An increase in the molybdenum content increases the corrosion resistance of the pitting and cracks on the stainless steel.
Model 316 (2% to 3% Mo) is the most widely used molybdenum-containing stainless steel. It is designated as a tank, pipe and heat exchanger material for food processing and processing and pharmaceutical production. Increased molybdenum content enhances resistance to chlorides in the air, so Type 316 can be used as a material of choice for offshore and coastal buildings. Model 316 is used to cover the Canary Wharf building in London and the tallest building in the world - the outer layer of the Petronas Tower in Kuala Lumpur, Malaysia.
Duplex stainless steel (3% to 4% Mo) has high strength and excellent resistance to chloride stress corrosion cracking. Multipurpose stainless steel, originally used as a transfer tube in the oil and gas industry, is now used more in the chemical processing and petrochemical industries and as a digester for the pulp and paper industry.
The most corrosion resistant stainless steel contains 6% to 7.3% Mo. Such alloy steels are used as power plant condensers, subsea pipelines, and key components of nuclear power plants, such as industrial water pipelines. In 1996, in a thermal power plant in South Korea, stainless steel containing 6% of Mo was used for the absorption tower containing more than 20 flue gas desulfurization scrubbers. [next]
Pitting/interstitial corrosion The passive chromium oxide layer is very sensitive near the grain boundaries and near non-metallic inclusions, forming microbatteries and rapidly producing pitting. Anoxic areas, such as under gaskets or lap joints, are very sensitive to similar corrosion and are often referred to as interstitial corrosion.
Molybdenum is the most effective and cheapest alloying element to prevent pitting corrosion and interstitial corrosion. Stainless steel in corrosive media exposed to high temperatures, especially in corrosive media containing chlorides and sulfides, where stress corrosion cracking (SCC) occurs if additional or residual tensile stresses are present. Increasing the molybdenum content is one of the most effective ways to improve the stress corrosion cracking of steel.
In scrubbers, pulp and paper, and chemical processing equipment in power plants operating in extremely harsh operating environments, alloys with very high molybdenum content are required. Alloys containing very high molybdenum include typical alloys containing 6% to 8% Mo and nickel-based alloys containing 10% to 16% Mo.
One of the earliest applications of tool steel and high-speed steel molybdenum is the use of tungsten as a substitute for tool steel and high-speed steel, which is effective and low-cost. The atomic weight of molybdenum is about half that of tungsten, so 1% of molybdenum is roughly equivalent to 2% of tungsten. Since these high-alloy steels are used for machining, cutting, and forming metal parts, they must have high hardness, high strength, and high toughness over a wide temperature range.
Cast Iron <br> Molybdenum increases the strength and hardness of cast iron by lowering the pearlite transformation temperature. It also increases the strength and creep resistance at high temperatures. High chromium cast iron containing 2% to 3% molybdenum exhibits greater impact toughness than high chromium cast iron without molybdenum and is ideal for use in harsh abrasive conditions, such as mining, milling, crushing, etc. Applications. These cast irons have acceptable performance, which eliminates the need for costly heat treatments, making them an inexpensive alternative to other abrasive materials. Reducing the austenite forming elements such as nickel and manganese also reduces the potential for premature failure of low temperature austenite retention.
The application of high Si-Mo plastic iron with a silicon content of 4% and a molybdenum content of 1% has attracted more and more interest. Their good strength at 600 ° C makes them an effective and inexpensive alternative to iron and steel with high alloy content in high temperature applications, such as in turbocharger housings, engine exhaust manifolds and furnace components. In the application. The austenitic quenched ductile iron has a unique microstructure with a strength exceeding 1000 MPa (145 ksi) and good impact toughness. Their specificity makes them ideal for special applications such as power transmission, ship engines and large gears and crankshafts required for large mining equipment. [next]
The most important limitation of powder metallurgy to improve the alloy content of high alloy ingot materials such as high speed steel is the tendency to segregate during slow cooling. Powder metallurgy technology atomizes the molten steel into droplets, and the droplets are cooled extremely quickly, preventing internal segregation. The steel produced by the coagulation of these particles has a fairly uniform microstructure and has numerous advantages over comparable conventional brand steels. Many powder metallurgy (PM) high speed steels, stainless steels and nickel based alloys have been put on the market, and this technology foreshadows the possibility of producing a new generation of high alloy steels in the future.
In the superalloy industry, powder metallurgy (PM) technology produces key parts with high alloy content, such as gas turbine components. Mo/Cu and W/Cu heat sinks for heat treatment in microelectronic devices.
Lubricating molybdenum disulfide is the most common form of molybdenum, which is used directly as a lubricant after extraction and purification from ore. Since molybdenum disulfide is a layered structure, it is a very effective lubricant. These delaminations can slide against each other, allowing free flow on steel and other metal surfaces, even under heavy pressure, such as bearing surfaces. Since molybdenum disulfide is formed by geothermal action, it has chemical stability against hot pressing. A small amount of sulfur reacts with the iron and forms a sulfide layer which is compatible with the molybdenum sulfide and maintains a lubricating film. Molybdenum disulfide is inert to many chemicals and will perform its lubrication under vacuum, while graphite does not.
Molybdenum disulfide has many unique properties compared to other solid lubricants, including:
1. Molybdenum disulfide is different from graphite, its friction coefficient is low (0.03 ~ 0.06), not caused by adsorption film or gas, lubricity is inherent in itself;
2. Strong affinity with metals;
3. having a film forming structure;
4. Yield strength up to 3450 MPa (500 psi);
5. Stability in most solvents;
6. Excellent air performance in air at 350 ° C (under 1200 ° C inert or vacuum conditions)
The molybdenum compound and the water-soluble sulfur compound solution are mixed to have lubricity and corrosion inhibition properties in the cutting fluid and the metal forming material. Oil-soluble molybdenum sulfur compounds, such as phosphates and thio thiocarbamates, can avoid wear, oxidation and corrosion of the engine. Several lubricant manufacturers have produced these lubricant additives.
Product introduction
Tire shredder is a professional shredding waste tires of mechanical equipment, using the principle of shear, can tear up the whole waste tires into 5-8cm rubber blocks, so as to smash later reuse or directly use. Tire shredding machine is my factory technical personnel on the basis of introducing and absorbing foreign advanced technology, accumulated many years of manufacturing experience, independent research and development design and production of a green waste recycling renewable shredding equipment, has a uniform discharge, tore up the advantages of high efficiency, large capacity, reliable performance, can be widely used in waste recycling industry.
Principle of equipment
Tire shredding machine tool is made of special alloy steel (high speed steel or tool steel) by special processing technology, with good wear resistance, high strength, can be repaired, etc. The driving part is driven by heavy-duty star gear reducer, which has the characteristics of low speed, large torque and low noise. Strong rotating shaft of large Angle hexagon column, so you can safely input large pieces of raw materials, automatic detection overload protection and reverse and other functions.
Characteristics of the equipment
1. 11 knives are installed on the tire shredding machine, 44 movable knives are installed on the rotating knife shaft, and the movable knives can be used on both sides, remove and change the Angle after being blunt, and then sharpen the knives after being blunt on both sides.
2. As it is claw type moving knife, rotary cutting, and fixed knife and moving knife are the material of SKD11 imported from Japan, the hardness of which reaches HRC60° after heat treatment, so the service life is long, the cutting ability is strong, the productivity is high, the normal use of more than 1000 tons need to sharpen the knife.
3. Equipped with conveyor belt, second-stage crusher, steel wire separator, nylon separator and grinding machine, so as to achieve automation, rationalization and labor-saving.
4. Effectively reduce labor intensity and improve working environment.
Tire Shredding Machine Equipment on Sale,Waste Tire Shredding Machine Equipment,Tire Shredding Machine Equipment
Shuangxing Mechanical Equipment Co.,Ltd , https://www.gyshuangxing.com