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Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
Molybdenum Market Overview of Current & Future Supply
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Molybdenum Market Overview of Current & Future Supply

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olybdenum Market Overview of Current & Future Supply

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  • 1. Molybdenum: UsesPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 2. Uses of MolybdenumPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 3. Uses of MolybdenumPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 4. Uses of MolybdenumPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 5. Molybdenum In Stainless SteelPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 6. Why Molybdenum Stainless Steels Molybdenum Increases Stainless Steel Pitting Resistance Pitting Resistance Equivalent Number (PREN) is a measure of the relative pitting corrosion resistance of stainless steel in a chloride-containing environment. Higher PREN values indicate greater corrosion resistance. The formula for PREN is: PREN = %Cr + 3.3*%Mo + 16*%N This formula suggests that molybdenum is 3.3 times more effective than chromium at improving pitting resistance, which is true within limits. Chromium must always be present in stainless steel to provide basic corrosion resistance. Molybdenum cannot provide this basic resistance, but it significantly enhances a stainless steels corrosion resistance, as the formula showsPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 7. Why Molybdenum Stainless Steels Comparison of PREN values for different ferritic, austenitic and duplex stainless steelsPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 8. Metallurgy of Mo in Stainless Steel Molybdenum adds corrosion resistance and high temperature strength. Corrosion Resistance Molybdenum primarily increases the corrosion resistance of stainless steels. Molybdenum containing stainless steels are thus used in applications that are more corrosive, such as chemical processing plants or in marine applications. Elevated Temperature Strength As a large atom, molybdenum increases the elevated temperature strength of stainless steels through solid solution hardening. Mo Stainless steels are used in heat exchangers and other elevated temperature equipment such as in automotive exhaust systems.Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 9. Metallurgy of Mo in Stainless Steel Molybdenum is a ferrite former Thus when molybdenum is added to improve the corrosion resistance of an austenitic stainless steel, there has to be an austenite former such as nickel or nitrogen added in order to keep the structure austenitic. Duplex stainless steels have a mixture of austenitic and ferritic grains in their microstructure; hence they have a “duplex” structure. This effect is achieved by adding less nickel than would be necessary for making a fully austenitic stainless steel. In austenitic stainless steels between two and seven percent are added, in duplex stainless steels, between three and five percent. The addition of one or two percent molybdenum to ferritic stainless steels also significantly increases the corrosion resistance and the elevated temperature strength of these stainless steels.Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 10. Molybdenum Stainless Steels Common ferritic, austenitic and duplex stainless steels AISI Cr Mo Ni N PREN Ferritic grades 409 11.5 11.5 430 16.5 16.5 434 16.5 1 19.8 436 17.5 1.25 21.6 444 17.7 2.1 24.6 Austenitic grades 304 18.1 8.3 18.1 316 17.2 2.1 10.2 24.1 317L 18.2 3.1 13.7 28.4 317LMN 17.8 4.1 12.7 0.14 33.6 904L 20 4.3 25 34.2 (6%Mo) 20 6.1 18-24 0.2 43.3 Duplex grades 2304 23 0.3 4.8 0.1 25.6 2205 22 3.1 5.7 0.17 35.0 2507 25 4 7 0.27 42.5Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 11. Molybdenum In Alloy Steel & Cast IronsPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 12. Molybdenum In Alloy Steel & Cast Irons Molybdenum in alloy steel & cast iron improves : • hardenability • reduce temper embrittlement • resist hydrogen attack & sulphide stress cracking • increase elevated temperature strength • improve weldability, especially in high strength low alloy steels (HSLA) End uses of Moly containing alloy steels and cast irons include : • Automotive, shipbuilding, aircraft and aerospace • Drilling, mining, processing • Energy generation, including boilers, steam turbines and electricity generators • Vessels, tanks, heat exchangers • Chemical & Petrochemical processing Typical % Mo content • Offshore; Oil Country Tubular Goods (OCTG) Heat Treatable Engineering Steel 0.25 - 0.5 Case Hardened Steel 0.15 - 0.5 High Temperature Steel 0.3 - 1.2 Oil Country Tubular Goods (OCTG) 0.3 - 1.0 HSLA Steel 0.15 - 0.25 Maraging Steels 4.0 - 5.0 Tool & High Speed Steel 0.5 - 9.0 Cast Iron 1.0 -3.0Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 13. Metallurgy of Mo in Alloy Steel & Iron The classic methods of strengthening low alloy steels are • solution hardening • quenching and tempering • precipitation hardening • controlled rolling Molybdenum is an effective strengthener in all cases. The large majority of low alloy steels are quenched and tempered. Mo helps reduce Hydrogen embrittlement and sulphide stress cracking through solid solution strengthening and the formation of complex carbides together with other elements such as chromium and niobium. The capability of molybdenum to provide resistance to sulphide stress cracking has been the key to the development of a broad range of steel grades used for Oil Country Tubular Goods and in chemical and petrochemical plants.Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 14. Heat Treatable Engineering Mo - Steel Demand of higher strength and toughness require increasing alloy content for improved hardenability by increasing : •Carbon content ( 0.22% to 0.55%) •1% Cr and 1% Cr / 0.25% Mo grades C from 0.25% to 0.55%. •Higher stressed components CrNiMo steels Ni, Cr: 1% and 2% and Mo 0.25% •Thru hardening steels (generator shafts etc) : NiCrMo steels Ni upto 4% and Mo upto 0.7% • CrMoV steels for good weldability or extra high toughness. C partly replaced by 0.9% Mo Molybdenum’s most important role in these grades is to increase the hardenability and to promote a uniformly hardened microstructure across the full cross section. Application include: • Automotive parts such as crankshafts, axle shafts, steering components, • Shafts in locomotive construction, shipbuilding and heavy engines • Parts for machine tools and general mechanical engineering • Turbine and generator shafts in power stations • Components and accessories for the oil and gas industry • Fastening elements such as high strength bolts • Landing gear and control elements in aviation • Tools in oil and gas explorationPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 15. Heat Treatable Engineering Mo - Steel GRADE C Cr Ni Mo APPLICATION 1% Cr and CrMo Steel 28Cr4 0.25 1 Driving wheels and shafts 25CrMo4 0.25 1 0.25 Axle arbors, turbine components 34Cr4 Popular Tata 0.34 1 Axle, axle arms 34CrMo4 Steel Grade 0.34 1 0.25 High toughness components, incl. crank shafts, axle arbors 41Cr4 upto ‘99 0.41 1 Axles, control components 42CrMo4 0.41 1 0.25 High toughness components for automobiles and aircraft 48CrMo4 0.5 1 0.25 Steel for induction hardening up to 250 mm Diameter 50CrMo4 0.5 1 0.25 High toughness components for automobiles and aircraft CrNiMo Steel 36CrNiMo4 0.36 1 1 0.25 Highly charged components for automobiles and aircraft 34CrNiMo6 0.34 1.5 1.5 0.25 Crank shafts, eccentric shafts, gear components 30CrNiMo8 0.3 2 2 0.4 Structural components for heavy demands NiCrMo Steel 28NiCrMo4 0.28 1 1 0.25 Structural components for very heavy demands 33NiCrMoV14-5 0.33 1.3 3.5 0.5 Generator shafts, high strengt & toughness components 36NiCrMo16 0.36 1.8 4 0.7 High strength mechanical engineering components CrMoV Steel 14CrMoV6-9 0.14 1.5 0.9 High strength welded components 30CrMoV9 0.3 2.25 0.25 High toughness crank shafts, screws, bolts All grades with Mn between 0.5 and 0.9%Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 16. See Annexure For More On Molybdenum ApplicationsPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 17. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 18. Molybdenum Mines - RegionsPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 19. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 20. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 21. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 22. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 23. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 24. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 25. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 26. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 27. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 28. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 29. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 30. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 31. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 32. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 33. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 34. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 35. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 36. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 37. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 38. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 39. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 40. Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 41. Back Up : Stainless Steel PropertiesPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 42. Stainless Steel Properties Select properties of austenitic and ferritic stainless steels Properties Austenitic Ferritic Toughness Very high Moderate Ductility Very high Moderate Weldability Good Limited Thermal expansion High Moderate Stress corrosion cracking resistance Low Very high Magnetic properties Non-magnetic Ferro magneticPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 43. Stainless Steel Properties Ferrite formers Austenite formers Iron Nickel Chromium Nitrogen Molybdenum Carbon Silicon Manganese CopperPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 44. Duplex Stainless Steel Duplex stainless steels are called “duplex” because they have a two-phase microstructure consisting of grains of ferritic and austenitic stainless steel. The duplex structure gives this family of stainless steels a combination of attractive properties: Strength: Duplex stainless steels are about twice as strong as regular austenitic or ferritic stainless steels. Toughness & Ductility: Duplex stainless steels have significantly better toughness and ductility than ferritic grades; however, they do not reach the excellent values of austenitic grades. Corrosion Resistance: For chloride pitting and crevice corrosion resistance, their chromium, molybdenum and nitrogen content are most important. Duplex stainless steel grades have a range of corrosion resistance, similar to the range for austenitic stainless steels, i.e from Type 304 or 316 (e.g. LDX 2101©) to 6% molybdenum (e.g. SAF 2507©) stainless steels.Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 45. Duplex Stainless Steel Stress corrosion cracking resistance: Duplex stainless steels show very good stress corrosion cracking (SCC) resistance, a property they have “inherited” from the ferritic side. SCC can be a problem under certain circumstances (chlorides, humidity, elevated temperature) for standard austenitics such as Types 304 and 316. Cost: Duplex stainless steels have lower nickel and molybdenum contents than their austenitic counterparts of similar corrosion resistance. Due to the lower alloying content, duplex stainless steels can be lower in cost, especially in times of high alloy surcharges. Additionally, it may often be possible to reduce the section thickness of duplex stainless steel, due to its increased yield strength compared to austenitic stainless steel. The combination can lead to significant cost and weight savings compared to a solution in austenitic stainless steels. Molybdenum improves pitting and crevice corrosion resistance, which is particularly helpful in preventing salt and corrosive pollution damage.Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 46. Alloy Steels – Case Hardening Mo Steels Case hardening Steel Tough core and a hard case are the target properties of components made of case hardened steel. That combination of wear resistance and fatigue strength in the surface and impact strength in the core zone is achieved by carburizing the surface layer of the component, which is subsequently quenched and tempered. Components produced that way with optimized properties between core and case include gear components of all kind, camshafts, cardan joints, driving pinions, link components, axles and arbors. Applications include: Transportation: Case hardened components are needed in any engine driven vehicle, whether its a small car, a race car, a truck or an ocean vessel. Energy generation: Gear wheels and components in large dimensions have to withstand both stress and wear in equipment such as hydroelectric power stations, wind turbine generators, propeller drives of drilling rigs or steam turbine gears of power stations. General mechanical engineering: forging presses, steel rolling equipment, machine tools; drivelines of mining equipment and heavy duty transmissions; earth moving equipment and heavy duty construction cranes. The combination of wear resiastance and fatigue strength is always a key characteristic of the case hardened steels used for these applications. For carburisation the steel is heated in a carbon releasing medium to a temperature where the base material is completely transformed into austenite (here the solubility for carbon is much higher than in the ferritic structure). This way the surface layer is carburised up to 0.7% carbon, while the carbon content of the core material is limited to about 0.25%. Quenching and tempering following the carburisation produces a high carbon martensitic structure near the surface, with great hardness and wear resistance, while the core retains its original strength and toughness properties.Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 47. Alloy Steels – Case Hardening Mo Steels Case hardening Steel Molybdenum (0.15 - 0.50%) is used in carburising steels to simultaneously increase the hardenability of the low carbon core and toughen the high carbon case. It is especially effective in large cross sections, such as in gears. Molybdenum is not oxidised during carburisation, making it an effective hardening agent which does not cause increased surface cracking and spalling. Standard case hardening Steels SAE % Alloy content DIN - EN /ASTM C Cr Mo Other MnCr Steel 20MnCr5 5120 0.2 1.2 1.3 Mn CrMo Steel 20MoCr4 0.2 0.4 0.5 20CrMo5 8620 0.2 1.2 0.25 NiCrMo Steel 20NiCrMo2-2 0.2 0.5 0.25 0.5 Ni 18CrNiMo7-6 0.18 1.7 0.3 1.5 NiPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 48. Alloy Steels – Case Hardening Mo Steels High Temperature Steel Molybdenum has been the key element to develop ferritic steels with good creep strength for service temperatures up to 530 °C. Products and components made of high temperature steels include • seamless tubes for water boilers and superheaters, boiler drums,collectors, pumps and pressure vessels for elevated temperature service • heavy steam turbine shafts with the diameter exceeding 2 meters, weighing more than 100 mt. •Molybdenum in solid solution is very efficient in reducing the creep rate of steel at elevated temperatures. Molybdenum slows the coagulation of carbides during high temperature service. The best results in terms of elevated temperature strength are obtained in quenched and tempered condition with an upper bainitic microstructure. •The family of Mo, CrMo and CrMoV steels continues to be the materials of choice for the worldwide installations of power plants, oil refineries and petrochemical plants In recent years, worldwide efforts to increase efficiency in power plants have created a demand for steels that can withstand higher pressure and higher service temperatures. A promising development is grade P/T91 – X10CrMoVNb9-1, which is a modification of the existing 9% Cr 1% Mo grade with additions of vanadium and niobiumPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 49. Mo Steels – Oil Country Tubular Goods (OCTG) OCTG include three types of seamless tubes, delivered in quenched and tempered condition: •Drill pipe – heavy seamless tubes that rotate the drill bit and circulate the drilling fluid. Joints of pipe 30 ft (9m) long are coupled together with tool joints •Casing pipe is used to line the hole. •Tubing – a pipe through which the oil or gas is produced from the wellbore. Tubing joints are generally around 30 ft [9 m] long with a thread connection on each end. Traditionally the grades used for for OCTG applications were carbon manganese steels (up to the 55 ksi strength level) or Mo containing grades up to 0.4% Mo. In recent years deep well drilling and reservoirs with contaminants causing corrosive attack have created strong demand for higher strength materials resistant to hydrogen embrittlement and sulphide stress cracking (SCC). Highly tempered martensite has been identified as the structure which is most resistant to SCC at higher strength levels, and 0.75% has been found to be the Mo concentration to obtain the optimum combination of yield strength and resistance to SCC (1). This is reflected in the list of Mo containing low alloy API standard grades. For the 75 ksi strength level 0.4% Mo is sufficient, while each of the the higher strength grades up to 125 ksi show the optimum Mo level of 0.75 or 0.80 % For higher strength up to 140 ksi (yield strength 965-1171 MPa) dispersion has been introduced as an additional strengthening mechanism by the addition of niobium. A non API specialized grade with 0.05% niobium; the molybdenum range is extended to 1.1% is used. For service in oil and gas fields with more aggressive corrosion environments stainless API grades are standardized with 9% Cr, 1% Mo and 13% Cr (without Mo). However, the 2% Mo grade can be used in lower pH and higher H2S environments.Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 50. Mo Steels – Oil Country Tubular Goods (OCTG) Country Tubular Good (OTCG) Steel Grades Low Alloy Grades Yield strength API Yield Strength Tensile Strength % Alloy content (ksi) Grade (0,2% proof stress) min (N/mm2) Code C Mn Ni Cr Mo Cu (N/mm2) 40 H40 0.5 1.5 276-552 410 55 K55 0.5 1.5 379~552 655 75 C75-1 0.5 1.7 0.5 0.5 0.4 0.5 517~620 665 90 C90-1 0.35 1.9 0.9 1.2 0.75 620~724 690 95 T95-1 0.35 1.2 0.9 1.5 0.85 655~758 724 125 Q125 0.35 1 0.9 1.2 0.75 860~1035 930 140 0.3 1 1.6 1.1 0.05 965~1171 1034 Country Tubular Good (OTCG) Steel Grades Stainless Steels Yield strength API Yield Strength Tensile Strength % Alloy content (ksi) Grade (0,2% proof stress) min (N/mm2) Code C Mn Ni Cr Mo Cu (N/mm2) 9% Chromium Stainless 75 C75-9Cr 0.15 0.6 0.5 9 1 0.25 517~620 665 13% Chromium Stainless 80 L80-13Cr 0.22 16 0.5 13 0.25 552~655 655 95/110 0.04 max 0.6 4 13 1.5 95/111 0.04 max 0.6 5 13 2.5Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 51. Mo Steels – High Strength Low Alloy Steel High strength low alloy (HSLA) steels have been developed since the 1960s originally for large diameter oil- and gas pipelines. The requirement was high strength as compared to mild carbon steel, combined with improved toughness and good weldability. HSLA steel typically contains 0.07 to 0.12% carbon, up to 2% manganese and small additions of niobium, vanadium and titanium in (usually max. 0.1%). in various combinations. The material is preferrably produced by a thermomechanical rolling process, which maximizes grain refinement as a basis for improved mechanical properties. Molybdenum has played an important role in the initial development. The addition of 0.1-0.2% molybdenum produces a fine grain structure of acicular ferrite and substantially enhances the precipitation hardening effects achieved with the other alloying elements. Consequently, an estimated 2 million tons of Mo containing HSLA steels for pipelines have been produced worldwide during the 1970s. During the following years developments of the rolling and cooling techniques resulted in improvements of the as rolled microstructure to the extent, that API X70- (70ksi yield strength) requirements can largely be met without the addition of molybdenum. However, for oil and gas transmission pipelines through regions with extreme climate conditions substantial quantities of molybdenum continue to be used to meet the low temperature toughness requirements of the steel. Likewise, for applications where the wall thickness exceeds 20 mm the addition of molybdenum is common to obtain a uniform structure with the desired combination of strength and toughness and good weldability properties. Presently, there is a strong trend towards increasing the operating pressure of the future long distance gas pipelines. This will take the required steel properties to X80 and higher. Steel producers are making good progress to meet this challenge, and it is not unlikely, that molybdenum will see a comeback in HSLA steels in that the present base formula ( e.g. 0.08 C, Nb, Ti) will be upgraded again with 0.1 to 0.2% Mo.Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 52. Mo Steels – High Strength Low Alloy Steel Composition range of HSLA steels (%) C Mn Nb V Mo 0.06 - 0.12 1.4 - 1.8 0.02 - 0.05 0 - 0.06 0.2 - 0.35Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 53. Mo Steels – Maraging Steels Maraging steels are carbon free iron-nickel alloys with additions of cobalt, molybdenum, titanium and aluminium. The term maraging is derived from the strengthening mechanism, which is transforming the alloy to martensite with subsequent age hardening. Air cooling the alloy to room temperature from 820°C creates a soft iron nickel martensite, which contains molybdenum and cobalt in supersaturated solid solution. Tempering at 480 to 500°C results in strong hardening due to the precipitation of a number of intermetallic phases, including, nickel-molybdenum, iron-molybdenum and iron-nickel varieties. With yield strength between 1400 and 2400 MPa maraging steels belong to the category of ultra-high-strength materials. The high strength is combined with excellent toughness properties and weldability. Typical applications areas include: •aerospace, e.g. undercarriage parts and wing fittings, •tooling & machinery , e.g. extrusion press rams and mandrels in tube production, gears •Ordnance components and fasteners. Maraging Steels Yield Strength % Alloy content Type (0,2% proof stress) (MPa) Ni Co Mo Ti Al 18Ni1400 1400 18 8.5 3 0.2 0.1 18Ni1700 1700 18 8 5 0.4 0.1 18Ni1900 1900 18 9 5 0.6 0.1 18Ni2400 2400 17.5 12.5 3.75 1.8 0.15 17Ni1600 (cast) 1600 17 10 4.6 0.3 0.05Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 54. Mo Steels – Tool & High Speed Steel One of the earliest applications of molybdenum was as an efficient and cost effective replacement for tungsten in tool steels and high- speed steels. The atomic weight of molybdenum is roughly half that of tungsten and therefore 1% Mo is roughly equivalent to 2% tungsten. Because these highly alloyed steels are used in the working, cutting and forming of metal components, they must possess high hardness and strength, combined with good toughness, over a broad temperature range. Tool Steels Molybdenum in tool steels increases their hardness and wear resistance. By reducing the critical cooling rate molybdenum promotes the formation of an optimal martensitic matrix, even in massive and intricate moulds which cannot be cooled rapidly without distortion or cracking. Molybdenum also acts in conjunction with elements like chromium to produce substantial volumes of extremely hard and abrasion resistant carbides. As the physical demands placed on tool steels increase, so too does the molybdenum content. High speed steels When tool steels contain a combination of more than 7% molybdenum, tungsten and vanadium, and more than 0.60% carbon, they are referred to as high speed steels. This term is descriptive of their ability to cut metals at high speeds. Until the 1950s, T-1 with 18% tungsten, was the preferred machining steel but the development of controlled atmosphere heat treating furnaces made it practical and cost effective to substitute part or all of the tungsten with molybdenum. Additions of 5-10% Mo effectively maximize the hardness and toughness of high-speed steels and maintain these properties at the high temperatures generated when cutting metals. Molybdenum provides another advantage: at high temperature, steels soften and become embrittled if the primary carbides of iron and chromium grow rapidly in size. Molybdenum, especially in combination with vanadium, minimizes this by causing the carbides to reform as tiny secondary carbides which are more stable at high temperatures. The largest use of high-speed steels is in the manufacture of various cutting tools: drills, milling cutters, gear cutters, saw blades, etc. Typical Compositions of Selected High-Speed Steels (%) % Molybdenum content in tool steels Grade C Cr Mo W V Steel type Mo T-1 0.75 - - 18 1.1 Plastic Moulding steels up to 0.5 M-2 0.95 4.2 5 6 2 Cold work steels 0.5 - 1.0 M-7 1 3.8 8.7 1.6 2 Hot work steels up to 3.0 M-42 1.1 3.8 9.5 1.5 1.2Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 55. Molybdenum Grade Cast Irons Molybdenum increases the strength and hardness of cast irons by depressing the pearlite transformation temperature. It also increases elevated temperature strength and creep resistance. High chromium irons, containing 2-3% molybdenum exhibit significantly greater impact toughness than Mo-free grades and are ideal for severe abrasive conditions like those encountered in mining, milling, crushing etc. These cast irons have acceptable properties as cast. This eliminates the need for a costly heat treatment and makes them a cost effective alternative to other grinding materials. Reduced levels of austenite formers, such as nickel and manganese, also minimize the retention of low temperature austenite - a potential cause of premature failures. There has been growing interest in the use of high silicon-molybdenum ductile irons with up to 4% Si and 1% Mo. Their good strength up to 600°C makes them a viable and cost effective replacement for more highly alloyed irons and steels in elevated temperature applications such as turbocharger housings, engine exhaust manifolds and furnace components. The austempered nodular irons develop a unique microstructure capable of strengths in excess of 1000 MPa (145 ksi) with good impact toughness. Their exceptional properties are ideal for critical applications such as the large gears and crankshafts required for power generation, ship propulsion and large mining equipment.Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 56. Other Molybdenum Alloys 1. Super Alloys 2. Molybdenum Metal & Alloys made by Power Metallurgy Techniques Other Applications Of mo Compounds 1. Catalysts - MoS2 in crude refining, Mo-based catalysts in coal liquification 2. Pigments - Molybdenum oranges, Zn-Mo White, Molybdophosphoric acid dyes 3. Corrosion inhibitors - Sodium molybdate as a substitute for chromates 4. Smoke suppressants - Ammonium octamolybdate is used with PVC 5. Lubricants - Molybdenum disulfide 6. Molybdenum chemicals in agriculture, pharmaceuticalsPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 57. Other Molybdenum Alloys & Chemicals 1. Super Alloys 2. Molybdenum Metal & Alloys made by Power Metallurgy Techniques Other Applications Of Mo Compounds 1. Catalysts - MoS2 in crude refining, Mo-based catalysts in coal liquification 2. Pigments - Molybdenum oranges, Zn-Mo White, Molybdophosphoric acid dyes 3. Corrosion inhibitors - Sodium molybdate as a substitute for chromates 4. Smoke suppressants - Ammonium octamolybdate is used with PVC 5. Lubricants - Molybdenum disulfide 6. Molybdenum chemicals in agriculture, pharmaceuticals Molybdenum-99 is a parent radioisotope to the daughter radioisotope technetium-99m, which is used in many medical procedures. Molybdenum disulfide (MoS2) is used as a solid lubricant and a high-pressure high-temperature (HPHT) antiwear agent. It forms strong films on metallic surfaces and is a common additive to HPHT greases—in case of a catastrophic grease failure, thin layer of molybdenum prevents contact of the lubricated parts. Molybdenum disilicide (MoSi2) is an electrically conducting ceramic with primary use in heating elements operating at temperatures above 1500 °C in air. Molybdenum trioxide (MoO3) is used as an adhesive between enamels and metals.] Lead molybdate (wulfenite) co- precipitated with lead chromate and lead sulfate is a bright-orange pigment used with ceramics and plastics. Molybdenum powder is used as a fertilizer for some plants, such as cauliflower.Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 58. Molybdenum Chemicals Aq NaOH, aq Na2MoO4 H2 NH3 (NH4)2Mo2O7 S (NH4)2MoS4 MoO3 Calcine/subli (NH4)6Mo7O24 me roast RS2 air MoCl5 H2 H2/CO NH3 [(RS2)2Mo2OxSy] 1000 1000 1000 C C C MoS2 CO 70 Cl bar 2 EtMgBr Mo2C Mo2N ice NH3 C+H2 1100 Mo 1500 C Mo(CO)6 CPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 59. Molybdenum Compounds Applications Application Partner C N O Si P S Mo2C Mo2N MoO3 MoSi2 MoP MoS2 molybdate Catalysis Lubrication Corrosion inhibition Pigments Smoke suppression Ceramics NanomaterialsPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 60. Molybdenum Catalysts Hydrotreatment of petroleum Remove S = hydrodesulfurisation = HDS Remove N, O compounds Selective oxidation Methanol to formaldehyde Propene to acrolein and acrylontrile For polymers and plasticsPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 61. Molybdenum Lubricants Molybdenum―sulfur Compounds in Lubrication 61 Molybdenum disulfide Dry lubricant Used in e.g. greases, dispersions, friction materials and bonded coatings. Molybdenum complexes soluble in petroleum oils Anti-wear and and other organic solvents extreme pressure additives Decompose at friction modifiers hot metal surface in lubricating oils and greases. Protective film MoS2 layerPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 62. Molybdenum Corrosion Inhibitors and Pigments Application Steel, Al, Cu Central heating Sodium molybdate systems Automobile engine coolant Paints Zinc, calcium, strontium molybdate plastics Molybdenum orange: lead molybdate + lead chromate rubber Phosphomolybdates ceramicsPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 63. Molybdenum Calcium Zinc Phosphomolybdate CorrosionPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 64. Molybdenum Calcium Zinc Phosphomolybdate Corrosion Mechanism of Protective Action of Molybdate Interacts with the metallic substrate ― adsorption. Fills gaps and promotes the formation of an adherent oxide layer. Prevents corrosion of the underlying substrate ― passivation.Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 65. Mechanism of Smoke Suppression by Molybdate Plasticizers ― greatly enhance the polymer combustibility. Molybdate reduces smoke from burning PVC. The char produced from the AOM containing compound was MoO2. Cross-links the plastic to form a surface char..Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 66. Molybdenum Carbide Catalyst NanotubesPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 67. Molybdenum Carbide Catalyst Nanotubes Series on Neutron Techniques and Applications – Vol. 3 Vibrational Spectroscopy with Neutrons With Applications in Chemistry, Biology, Materials Science and CatalysisPrabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation
  • 68. Why Molybdenum ? WHY USE MOLYBDENUM? Chemical versatility Low toxicity ALWAYS WORTH THINKING MOLYBDENUM Cr Can FAMD Get Into Mn Molybdenum ? next ?Prabhash Gokarn Head M&BD, Tata Steel Molybdenum Presentation

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