Molybdenum Market Overview of Current & Future Supply

Prabhash Gokarn Head M&BD, Tata SteelPrabhash Gokarn Head M&BD, Tata Steel Molybdenum PresentationMolybdenum Presentation

Molybdenum: UsesMolybdenum: Uses


Uses of Molybdenum


Uses of MolybdenumUses of Molybdenum


Uses of MolybdenumUses of Molybdenum


Molybdenum In Stainless SteelMolybdenum In Stainless Steel


Why Molybdenum Stainless SteelsWhy 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*%NPREN = %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 steel's

corrosion resistance, as the formula shows


Why Molybdenum Stainless SteelsWhy Molybdenum Stainless Steels

Comparison of PREN values for different ferritic, austenitic and duplex stainless steels


Metallurgy of Mo in Stainless SteelMetallurgy 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.


Metallurgy of Mo in Stainless SteelMetallurgy 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.


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 42.5

Molybdenum Stainless SteelsMolybdenum Stainless Steels


Molybdenum In Alloy Steel & Cast IronsMolybdenum In Alloy Steel & Cast Irons


Molybdenum In Alloy Steel & Cast IronsMolybdenum 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

• Offshore; Oil Country Tubular Goods (OCTG)Typical % Mo content

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 -3.0


Metallurgy of Mo in Alloy Steel & IronMetallurgy of Mo in Alloy Steel & Iron

The classic methods of strengthening low alloy steels are• solution hardening• quenching and tempering• precipitation hardening• controlled rollingMolybdenum is an effective strengthener in all cases. The large majority of low alloysteels are quenched and tempered.

Mo helps reduce Hydrogen embrittlement and sulphide stress cracking through solidsolution strengthening and the formation of complex carbides together with otherelements such as chromium and niobium.

The capability of molybdenum to provide resistanceto sulphide stress cracking has been the key to thedevelopment of a broad range of steel grades used forOil Country Tubular Goods and in chemical andpetrochemical plants.


Heat Treatable Engineering Mo Heat Treatable Engineering Mo -- SteelSteel

Demand of higher strength and toughness require increasing alloy content for improvedhardenability 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% MoMolybdenum’s most important role in these grades is to increase the hardenability and topromote 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 exploration


Heat Treatable Engineering Mo Heat Treatable Engineering Mo -- SteelSteel

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 0.34 1 Axle, axle arms

34CrMo4 0.34 1 0.25 High toughness components, incl. crank shafts, axle arbors

41Cr4 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%

Popular Tata

Steel Grade

upto ‘99


See Annexure For More On Molybdenum See Annexure For More On Molybdenum ApplicationsApplications



Molybdenum Mines - Regions
























Back Up : Stainless Steel PropertiesBack Up : 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 magnetic

Stainless Steel PropertiesStainless Steel Properties


Stainless Steel PropertiesStainless Steel Properties

Ferrite formers Austenite formers

Iron Nickel

Chromium Nitrogen

Molybdenum Carbon

Silicon Manganese

Copper


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.


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.


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 it's 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.



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

DIN - ENSAE

/ASTM

% Alloy content

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 Ni



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

niobium


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.


Mo Steels – Oil Country Tubular Goods (OCTG)

Country Tubular Good (OTCG) Steel GradesLow Alloy Grades

Yield strength API Grade Code

% Alloy contentYield Strength Tensile Strength

(ksi) (0,2% proof stress) min (N/mm2)C Mn Ni Cr Mo Cu (N/mm2)

40 H40 0.5 1.5 276-552 41055 K55 0.5 1.5 379~552 65575 C75-1 0.5 1.7 0.5 0.5 0.4 0.5 517~620 66590 C90-1 0.35 1.9 0.9 1.2 0.75 620~724 69095 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 930140 0.3 1 1.6 1.1 0.05 965~1171 1034

Country Tubular Good (OTCG) Steel GradesStainless Steels

Yield strength API Grade Code

% Alloy contentYield Strength Tensile Strength

(ksi) (0,2% proof stress) min (N/mm2)C Mn Ni Cr Mo Cu (N/mm2)

9% Chromium Stainless75 C75-9Cr 0.15 0.6 0.5 9 1 0.25 517~620 665

13% Chromium Stainless80 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 2.5


Mo Steels – High Strength Low Alloy SteelHigh 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.


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 - 0.35


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

Type

Yield Strength% Alloy content

(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 0.05


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 1950's, 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.

% Molybdenum content in tool steels

Steel type Mo

Plastic Moulding steels up to 0.5

Cold work steels 0.5 - 1.0

Hot work steels up to 3.0

Typical Compositions of

Selected High-Speed Steels (%)

Grade C Cr Mo W V

T-1 0.75 - - 18 1.1

M-2 0.95 4.2 5 6 2

M-7 1 3.8 8.7 1.6 2

M-42 1.1 3.8 9.5 1.5 1.2


Molybdenum Grade Cast Irons

Molybdenum increases the strength and hardness of cast irons by depressing the pearlite transformationtemperature. 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 areideal for severe abrasive conditions like those encountered in mining, milling, crushing etc. These cast ironshave acceptable properties as cast. This eliminates the need for a costly heat treatment and makes them acost effective alternative to other grinding materials. Reduced levels of austenite formers, such as nickel andmanganese, also minimize the retention of low temperature austenite - a potential cause of prematurefailures.

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 highlyalloyed irons and steels in elevated temperature applications such as turbocharger housings, engine exhaustmanifolds and furnace components. The austempered nodular irons develop a unique microstructurecapable of strengths in excess of 1000 MPa (145 ksi) with good impact toughness. Their exceptionalproperties are ideal for critical applications such as the large gears and crankshafts required for powergeneration, ship propulsion and large mining equipment.


Other Molybdenum Alloys

1. Super Alloys2. Molybdenum Metal & Alloys made by Power Metallurgy Techniques

Other Applications Of mo Compounds

1. Catalysts - MoS2 in crude refining, Mo-based catalysts in coal liquification2. Pigments - Molybdenum oranges, Zn-Mo White, Molybdophosphoric acid dyes3. Corrosion inhibitors - Sodium molybdate as a substitute for chromates4. Smoke suppressants - Ammonium octamolybdate is used with PVC5. Lubricants - Molybdenum disulfide6. Molybdenum chemicals in agriculture, pharmaceuticals


Other Molybdenum Alloys & Chemicals

1. Super Alloys2. Molybdenum Metal & Alloys made by Power Metallurgy Techniques

Other Applications Of Mo Compounds

1. Catalysts - MoS2 in crude refining, Mo-based catalysts in coal liquification2. Pigments - Molybdenum oranges, Zn-Mo White, Molybdophosphoric acid dyes3. Corrosion inhibitors - Sodium molybdate as a substitute for chromates4. Smoke suppressants - Ammonium octamolybdate is used with PVC5. Lubricants - Molybdenum disulfide6. Molybdenum chemicals in agriculture, pharmaceuticals

Molybdenum-99 is a parent radioisotope to the daughter radioisotope technetium-99m, which is used inmany medical procedures. Molybdenum disulfide (MoS2) is used as a solid lubricant and a high-pressurehigh-temperature (HPHT) antiwear agent. It forms strong films on metallic surfaces and is a commonadditive to HPHT greases—in case of a catastrophic grease failure, thin layer of molybdenum preventscontact of the lubricated parts. Molybdenum disilicide (MoSi2) is an electrically conducting ceramic withprimary use in heating elements operating at temperatures above 1500 °C in air. Molybdenumtrioxide (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 andplastics. Molybdenum powder is used as a fertilizer for some plants, such as cauliflower.


Molybdenum Chemicals

MoS2

MoO3

Mo

Mo2C

MoCl5

(NH4)2MoS4

[(RS2)2Mo2OxSy]

Mo2N

Na2MoO4

(NH4)2Mo2O7

(NH4)6Mo7O24

Mo(CO)6

roast air

Aq NaOH, aq NH3

Calcine/sublime

H2/CO 1000 C

H2

1000 C

NH3

1000 C

C+H2

1500 C

NH3

1100 C

Cl

2

CO 70 barEtMgBrice

H2

S

RS2


Molybdenum Compounds Applications

Application Partner

C N O Si P S

Mo2NMoO3

molybdateMoSi2 MoP MoS2

Catalysis

Lubrication

Corrosioninhibition

Pigments

Smoke suppression

Ceramics

Nanomaterials

Mo2C


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 plastics


Molybdenum Lubricants

61Molybdenum―sulfur Compounds in Lubrication

Molybdenum disulfide

Used in e.g. greases, dispersions, friction materials and bonded coatings.

Dry lubricant

Molybdenum complexes

Anti-wear and extreme pressure additives

friction modifiers in lubricating oils and greases.

soluble in petroleum oils and other organic solvents

Decompose at hot metal surface Protective filmMoS2 layer


Molybdenum Corrosion Inhibitors and Pigments

Application

Steel, Al, Cu

Sodium molybdateCentral heating

systems

Automobile engine

coolant

Paints

plastics

rubber

ceramics

Zinc, calcium, strontium molybdate

Molybdenum orange: lead molybdate

+ lead chromate

Phosphomolybdates


Molybdenum Calcium Zinc Phosphomolybdate Corrosion


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.


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..


Molybdenum Carbide Catalyst Nanotubes


Molybdenum Carbide Catalyst Nanotubes

Vibrational Spectroscopy with Neutrons With Applications in Chemistry,

Biology, Materials Science and Catalysis

Series on Neutron Techniques and Applications –

Vol. 3


WHY USE MOLYBDENUM?

Chemical versatility

Low toxicity

ALWAYS WORTH THINKING MOLYBDENUM

Why Molybdenum ?

Can FAMD Get Into Molybdenum ?

Cr Mn

next ?

Date post:	11-May-2015
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Molybdenum Market Overview of Current & Future Supply

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