Molybdenum Wire

Molybdenum is a metal silvery in color with properties that make it one of the most prized industrial metals. It melts at 4,753 degrees Fahrenheit (2,623 degrees Celsius) — one of the highest melting points of any metal — and has the ability to withstand very high pressure and temperature without softening or expanding much. These properties make molybdenum wire useful in various products, like automotive and aircraft components, electric vacuum devices, light bulbs, heating elements, and high-temperature furnaces. Molybdenum wire can also be used for printer needles and other printer parts. Depending on what the molybdenum wire is to be used for, it can be made from pure molybdenum, from a mix of molybdenum and other materials such as potassium silicate, or from alloys of molybdenum and other metals, for example tungsten.

Molybdenum wire is often used to make parts that provide structural support, even at very high temperatures. For example, it is commonly used for various furnace components, like heating elements, outlets and windings. Its high melting point makes molybdenum wire suitable for specialized, high-temperature furnaces featuring hydrogen or vacuum atmospheres.
 

Cleaned Molybdenum Wire

Spray Molybdenum Wire

Black Molybdenum Wire

Another common use for molybdenum wire is as parts for light bulbs. For example, it can be used in the manufacture of supports for lamp filaments made from tungsten, to make leads for halogen lamp bulbs, and to make electrodes for gas discharge lamps and tubes. This type of wire is also used in the windshields of airplanes, where it functions as a heating element, providing defrosting. Molybdenum wire is also used in the manufacture of electron tubes and power tube grids.

The surface of the wire can either be clean or coated. Coated wire is black in color, because it is covered in oxides and lubricants. The tensile strength of wire is often an important consideration in manufacturing, and also affects the appearance of the wire: the more tensile strength, the less straight the wire is.

Molybdenum wire commonly comes in sizes from 0.001 inches (0.025 mm) in diameter, to 0.25 inches (6.35 mm) in diameter. Its size can be measured either in inches, or in mils, with 1 mil being equal to one thousandth of an inch. For very thin wire, the size is expressed in the form of weight of a certain length of wire, rather than by diameter. Molybdenum is similar in appearance to lead, and even received its name from the Greek word for lead, molybdos, because it was often mistaken for lead in ancient times.

Molybdenum Crucible Applications

1、Description of Molybdenum Crucible
* Mo content: Over than 99.95%.
* Density: Over than 9.8g/cm3
* Diameter: 100-220 mm
* Height: 100-400 mm
* Temperature: 1100 C
Packing: Plastic inside and Wooden case outside

Molybdenum Crucibles

2、There are three technologies using in making molybdenum crucible, as following:
(1) pressing --> sintering --> tooling.
(2) pressing --> sintering --> forging --> tooling.
(3) sheets --> deep drawing --> tooling

3、Molybdenum Crucible Applications:
Molybdenum crucible is sintered or forged from the ultimate material—molybdenum powder. Generally speaking, molybdenum crucible is used pure molybdenum, for its purity can prevent melting metal powder from mingling. The density of molybdenum crucible is more than 9.8g/cm3, and its working temperature is among 1100℃. Therefore, it is another ring choice, besides tungsten crucible in metal melting industry.
Molybdenum crucible is widely used in metallurgical industry, rare earth industry, artificial crystal and machinery.
Molybdenum crucible is widely used in metallurgical industry, rare earth industry, artificial crystal, and machinery.

Two Kinds of Molybdenum Electrode Material

1. Molybdenum electrode
Appearance: Silver gray metallic luster
No defects (lose side, lose corner, divide layer, crackle)
To bend or align according to the needs of users
Density: 9.8g/cm3
purity : Mo 99.95%
Dimension : (14-20) * (14-20) * L L max 500mm
Main applications: Molybdenum electrode is used as electro-heat equipment of the glass fiber kiln
The impurity content accords with GB3462-82 standard

Molybdenum Electrodes

2. Molybdenum electrode plate
Dark brown , silver gray metallic luster if washed by the alkali (produced according to user's request )
Purity : Mo 99.95%
Density: 10.15g/m3
Dimension : (3 - 25)* (50 -500) *L L max800mm (Unit weight is not more than 40 kgs) special specification should be consulted by both parties
Main applications: Molybdenum electrode plate can be used as various kinds of heating equipment of glass fiber kiln, liquid-flow hole panel, etc.
The impurity content accords with GB3876-83 standard

Molybdenum Electrodes

3. Molybdenum electrode bars
Appearance: Bright silver gray metallic luster . (process according to user's drawing , surface finish is higher)
purity : Mo 99.93%
Density: 10.15g/cm3
Unit weight: The special dimension of various kinds of Molybdenum electrodes under 70kgs is consulted by both parties.
Dimension: produced according to the needs of users : (φ20 - φ100) *L (mm)
Main applications: Molybdenum electrode bar is mainly used as the furnace , electric boosting glass kiln electrode , etc
The impurity content accords with the standard of GB/t17792-1999.

The specification of molybdenum electrode

Description	Code	Density (g/cm3)	Size of finished product (mm)
Molybdenum electrode bar	Mo-4.2	9.3	14*20*(400-520) 17*17*(400-520) 20*20*(530-540)
Molybdenum electrode plated	BMo-4.2	9.9	(60-160)*(160-500)*(3-7)

TZM Alloy

The earliest molybdenum alloy is titanium-zirconium-molybdenum alloy (TZM) in industry. Titanium-zirconium-molybdenum alloy (TZM) is famous for it's properties of higher strength, better electronic and heat conductivity and corrosion resistance, lower ductility and vapor pressure, higher temperature of recrystallization and relatively easier to be processed than other refractory metals. 

TZM with the least content of titanium, zirconium and carbon is in the leader in these alloys. TZM is a kind of alloy with (0.5 titanium, 0.08 zirconium, 0.02 carbon) and the margin of TZM is molybdenum. There are two methods of producing TZM: smelting process and powder-alchemical process.

TZM Rods

Application

TZM is widely used in aviation, aerospace industry, such as: materials used for the nozzle, buried pipes and electronic tubes and so on. TZM also is applied to semiconductor products and medical field，for example, the cathode assembles in X-ray target. TZM can also be used as heating elements in high-temperature furnace, heat shield, light alloy forging etc.

The Molybdenum-Copper Heat Sinks

Molybdenum-Copper Heat Sinks are composites of molybdenum and copper. Similar to W-Cu, CTE of Mo-Cu can also be tailored by adjusting the content of molybdenum. Mo-Cu is much lighter than W-Cu so that it is suitable for aeronautic and astronautic applications.They are widely used in applications such as optoelectronics packages, Microwave Packages, C Packages, Laser Submounts, etc.

1. Advantages:
High thermal conductivity since no sintering additives have been usedExcellent hermeticityRelatively small densityStampable sheets available (Mo content no more than 75 wt%)Semi-finished or finished (Ni/Au plated) parts available.

2. Technical Data:

Type	Molybdenum Content (wt%)	Density (g/cm3)	CTE (ppm/K)	Thermal Conductivity (W/m.K)
Mo70cu	70±1	9.8	9.1	170 - 200
Mo60cu	60±1	9.66	10.3	210 - 250
Mo50cu	50±1	9.54	11.5	230 - 270

The Advantages And Application of Molybdenum Copper

Molybdenum Copper alloy is the composite material of Molybdenum and Copper. It has the similar performances as Tungsten Copper alloy. But its density is less than Tungsten Copper alloy’s, so it is more suitable for spaceflight and navigation industries.

1. Typical Physical and Mechanical Properties:

Material Composition	Density (g/cm3)	Thermal Conductivity W/moK 25°C	Coefficient of Thermal Expansion 10-6/°C
85Mo/15Cu	10.01	195	7.0
80Mo/20Cu	9.96	204	7.6
70Mo/30Cu	9.75	208	8.0
60Mo/40Cu	9.62	223	9.3
50Mo/50Cu	9.51	230	10.3

2. Advantages of Molybdenum Copper (MoCu):

Thermal expansion can be design; High thermal conductivity; Precision flatness capability; Bondable gold plating; Thickness from .004" to .500"; Zero corner radius; Integrated ribs; Precision complex geometry; Low thermal expansion; Good electrical conductivity; High wear resistance; More lighter than W-Cu.

3. Typical areas Application:

Heat Sinks and Spreaders
Microwave Carriers
Microelectronic Package Bases and Housings
Ceramic Substrate Carriers
GaAs and Silicon Device Mounts
Laser Diode Mounts
Surface Mount Package Conductors
Microprocessor Lids
Rocket Parts
Optical Packages
Power Packages
Butterfly Packages

Molybdenum Applications

Molybdenum is a silvery grey metal that is not found in a pure state in nature. It is usually associated with other elements, such as is the case of sulfurated ores, from which one can also obtain copper. Thus it is common for molybdenum to be regarded as a byproduct of the copper extraction operation.

In the periodic table of chemical elements, molybdenum is identified with number 42 and the symbol Mo. It melts at a temperature of 2,610 degrees Celsius.

Its name originates from the Greek word, “molybdos”, meaning “lead-like”, in a clear allusion to its color. Although some say that it was known in ancient times, it was only during the World War I that its use in steel alloys was made known. Molybdenum was utilized instead of wolfram (aka tungsten) that in those times was scarce, and so began its commercial application.

Black Molybdenum Wire

Molybdenum Electrode

Molybdenum Apply In Plane

Molybdenum Disilicide Rod

Its main characteristics are durability, strength and resistance to corrosion and high temperatures.

Molybdenum is a metal used as raw material in order to obtain alloys, among which more resistant steel stands out. Approximately two thirds of this metal is used for this purpose, also known as inox, with contents up to 6%.

The steel alloy withstands high temperatures and pressures, being very resistant. This is why it is used in construction, to manufacture airplane parts and wrought car parts. Molybdenum wires are utilized in electronic tubes and the metal also functions as electrode in glass furnaces.

Among its many applications is a super-alloy that can be obtained from a nickel base, to produce catalysts which are used to eliminate sulfur in the oil industry.

In addition, it is utilized in the industrial process of lubricants (molybdenum disulfide is resistant to high temperatures, reduces wear and friction of motor parts – as may be the case of vehicle brakes), in the manufacture of linings and solvents, in the chemical industry (pigments for plastics, paints and rubber compounds) and in the electronic industry (electric conductors).

Molybdenum is also deemed to be a strategic material and has multiple applications in the aerospace and automobile industries, for surgical tools, as well as for manufacturing light bulbs (filament) and LCD screens, for water treatment and even for applying laser beams.

Molybdenum Element

Molybdenum

Atomic Number: 42
Atomic Weight: 95.96
Melting Point: 2896 K (2623°C or 4753°F)
Boiling Point: 4912 K (4639°C or 8382°F)
Density: 10.2 grams per cubic centimeter
Phase at Room Temperature: Solid
Element Classification: Metal
Period Number: 5    Group Number: 6    Group Name: none
Estimated Crustal Abundance: 1.2 milligrams per kilogram
Estimated Oceanic Abundance: 1×10-2 milligrams per liter
Number of Stable Isotopes: 6   (View all isotope data)
Ionization Energy: 7.092 eV
Oxidation States: +6

Mo Element

Molybdenum Concemtrate

Molybdenum was discovered by Carl Welhelm Scheele, a Swedish chemist, in 1778 in a mineral known as molybdenite (MoS2) which had been confused as a lead compound. Molybdenum was isolated by Peter Jacob Hjelm in 1781. Today, most molybdenum is obtained from molybdenite, wulfenite (PbMoO4) and powellite (CaMoO4). These ores typically occur in conjunction with ores of tin and tungsten. Molybdenum is also obtained as a byproduct of mining and processing tungsten and copper.

Molybdenum has a high melting point and is used to make the electrodes of electrically heated glass furnaces. Some electrical filaments are also made from molybdenum. The metal is used to make some missile and aircraft parts and is used in the nuclear power industry. Molybdenum is also used as a catalyst in the refining of petroleum.

Molybdenum is primarily used as an alloying agent in steel. When added to steel in concentrations between 0.25% and 8%, molybdenum forms ultra-high strength steels that can withstand pressures up to 300,000 pounds per square inch. Molybdenum also improves the strength of steel at high temperatures. When alloyed with nickel, molybdenum forms heat and corrosion resistant materials used in the chemical industry.

Molybdenum disulphide (MoS2), one of molybdenum's compounds, is used as a high temperature lubricant. Molybdenum trioxide (MoO3), another molybdenum compound, is used to adhere enamels to metals. Other molybdenum compounds include: molybdic acid (H2MoO4), molybdenum hexafluoride (MoF6) and molybdenum phosphide (MoP2).

What Is Molybdenum Deficiency?

Most cases of molybdenum deficiency occur in those who were born without the enzyme required to break down the mineral, resulting in very rare recessive metabolism disorders. There has only been one well-documented case of acquired molybdenum deficiency. The patient developed rapid heart and respiratory rates, night blindness and eventually became comatose.

Molybdenum requirements are relatively low in humans. In addition, molybdenum can be easily obtained through a diet of beans, dark green leafy vegetables, and certain grains. In fact, lack of molybdenum has never been observed in a completely healthy patient. Those with the greatest risk of developing it are patients being fed intravenously. For those who suffer from molybdenum deficiency, change in diet or taking molybdenum supplements can reverse the condition.

Though the two are connected, molybdenum deficiency should not be confused with molybdenum cofactor deficiency. Molybdenum cofactor deficiency is a rare metabolic disorder in which the body lacks the xanthine dehydrogenase enzyme, the aldehyde oxidase enzyme, and the sulfite oxidase enzyme. These enzymes are all required to metabolize xanthine, a base that is changed into the uric acid needed for healthy brain function. Molybdenum cofactor deficiency can result in severe neurological symptoms including seizures and coma.

Molybdenum in Pumpkin

DNA

Molybdenum as a mineral has several benefits for the human body. It is essential to liver function, helping the liver filter the body’s blood. Molybdenum regulates calcium, magnesium, and copper metabolism. It also facilitates the body’s use of iron, which is necessary to normal growth and development. Molybdenum has been associated with bone growth and lowered risk of tooth decay. Some studies even link this mineral with low risk of stomach and esophagus cancer.

Too much molybdenum can be bad for the body too. Large amount of molybdenum can cause the body to use copper or alter the activity of alkaline phosphatase. Some side effects of too much molybdenum are diarrhea, anemia, and swelling of joints. While getting too much molybdenum is not good for the body, it is just as rare as molybdenum deficiency, because the body quickly excretes the mineral if it is consumed in large quantities.

Molybdenum in the Environment

Molybdenum differs from the other micronutrients in soils in that it is less soluble in acid soils and more soluble in alkaline soils, the result being that its availability to plants is sensitive to pH and drainage conditions. Some plants can have up to 500 ppm of the metal when they grow on alkaline soils.

Molybdenum Product

Molybdenite is the chief mineral ore, with wulfenite being less important. Some molybdenite is obtained as a by-product of tungsen and copper production. The main mining areas are the USA, Chile, Canada and Russia, with world production being around 90.000 tonnes per year, and reserves amounting to 12 million tonnes of which 5 million tonnes are in the USA.

Health effects of molybdenum
Based on animal experiments, molybdenum and its compounds are highly toxic. Some evidence of liver dysfunction with hyperbilirubinemia has been reported in workmen chronically exposed in a Soviet Mo-Cu plant. In addition, signs of gout have been found in factory workers and among inhabitants of Mo-rich areas of Armenia. The main features were joint pains in the knees, hands, feet, articular deformities, erythema, and edema of the joint areas

Environmental effects of molybdenum
Molybdenum is essential to all species. As with other trace metals, though, what is essential in tiny amounts can be highly toxic at larger doses. Animal experiment have shown that too much molybdenum causes fetal deformities. Fodder with more than 10 ppm of molybdenum would put most livestok at risk.

Pure Molybdenum Production

In molybdenite processing, the molybdenite is first heated to a temperature of 700 °C (1,292 °F) and the sulfide is oxidized into molybdenum(VI) oxide by air: 2 MoS2 + 7 O2 → 2 MoO3 + 4 SO2  The oxidized ore is then either heated to 1,100 °C (2,010 °F) to sublimate the oxide, or leached with ammonia which reacts with the molybdenum(VI) oxide to form water-soluble molybdates:  MoO3 + 2 NH4OH → (NH4)2(MoO4) + H2O.

Molybdenum Powder

Copper, an impurity in molybdenite, is less soluble in ammonia. To completely remove it from the solution, it is precipitated with hydrogen sulfide. Pure molybdenum is produced by reduction of the oxide with hydrogen.

While the molybdenum for steel production is reduced by the aluminothermic reaction with addition of iron to produce ferromolybdenum. A common form of ferromolybdenum contains 60% molybdenum.

History of Molybdenum

Molybdenite—the principal ore from which molybdenum is now extracted—was previously known as molybdena. Molybdena was confused with and often utilized as though it were graphite. Like graphite, molybdenite can be used to blacken a surface or as a solid lubricant. Even when molybdena was distinguishable from graphite, it was still confused with the common lead ore PbS (now called galena); the name comes from Ancient Greek Μόλυβδος molybdos, meaning lead. (The Greek word itself has been proposed as a loanword from Anatolian Luvian and Lydian languages).

Although apparent deliberate alloying of molybdenum with steel in one 14th-century Japanese sword (mfd. ca. 1330) has been reported, that art was never employed widely and was later lost. In in the West in 1754, Bengt Andersson Qvist examined molybdenite and determined that it did not contain lead, and thus was not the same as galena.

 

By 1778 Swedish chemist Carl Wilhelm Scheele stated firmly that molybdena was (indeed) not galena nor graphite. Instead, Scheele went further and correctly proposed that molybdena was an ore of a distinct new element, named molybdenum for the mineral in which it resided, and from which it might be isolated. Peter Jacob Hjelm successfully isolated molybdenum by using carbon and linseed oil in 1781.

 

MoS2

Molybdenum Powder

Molybdenum Trioxide

Molybdenum Concentrate

For about a century after its isolation, molybdenum had no industrial use, owing to its relative scarcity, difficulty extracting the pure metal, and the immaturity of appropriate metallurgical techniques. Early molybdenum steel alloys showed great promise in their increased hardness, but efforts to manufacture them on a large scale were hampered by inconsistent results and a tendency toward brittleness and recrystallization. In 1906, William D. Coolidge filed a patent for rendering molybdenum ductile, leading to its use as a heating element for high-temperature furnaces and as a support for tungsten-filament light bulbs; oxide formation and degradation require that molybdenum be physically sealed or held in an inert gas. In 1913, Frank E. Elmore developed a flotation process to recover molybdenite from ores; flotation remains the primary isolation process.

 

During the first World War, demand for molybdenum spiked; it was used both in armor plating and as a substitute for tungsten in high speed steels. Some British tanks were protected by 75 mm (3 in) manganese steel plating, but this proved to be ineffective. The manganese steel plates were replaced with 25 mm (1 in) molybdenum-steel plating allowing for higher speed, greater maneuverability, and better protection. The Germans also used molybdenum-doped steel for heavy artillery. This was because traditional steel melted at the heat produced by enough gunpowder to launch a one ton shell. After the war, demand plummeted until metallurgical advances allowed extensive development of peacetime applications. In World War II, molybdenum again saw strategic importance as a substitute for tungsten in steel alloys.

Occurrence of Molybdenum

Molybdenum is the 54th most abundant element in the Earth's crust and the 25th most abundant element in the oceans, with an average of 10 parts per billion; it is the 42nd most abundant element in the Universe. The Russian Luna 24 mission discovered a molybdenum-bearing grain (1 × 0.6 µm) in a pyroxene fragment taken from Mare Crisium on the Moon. The comparative rarity of molybdenum in the Earth's crust is offset by its concentration in a number of water-insoluble ores, often combined with sulfur, in the same way as copper, with which it is often found. Though molybdenum is found in such minerals as wulfenite (PbMoO4) and powellite (CaMoO4), the main commercial source of molybdenum is molybdenite (MoS2). Molybdenum is mined as a principal ore, and is also recovered as a byproduct of copper and tungsten mining.

Mo Element

Wulfenite

Historically, the Knaben mine in southern Norway, opened in 1885, was the first dedicated molybdenum mine. It closed from 1973–2007, but is now reopened. Large mines in Colorado (such as the Henderson mine and the Climax mine) and in British Columbia yield molybdenite as their primary product, while many porphyry copper deposits such as the Bingham Canyon Mine in Utah and the Chuquicamata mine in northern Chile produce molybdenum as a byproduct of copper mining.

 

The world's production of molybdenum was 250,000 tonnes in 2011, the largest producers being China (94,000 t), United States (64,000 t), Chile (38,000 t), Peru (18,000 t) and Mexico (12,000 t). The total reserves are estimated at 10 million tonnes, and are mostly concentrated in China (4.3 mt), US (2.7 mt) and Chile (1.2 mt). By continent, 93% of world molybdenum production is about evenly split between North America, South America (mainly in Chile), and China. Europe and the rest of Asia (mostly Armenia, Russia, Iran and Mongolia) produce the remainder.

 

Molybdenum Compounds

Molybdenum is a transition metal with an electromagnetically of 2.16 on the Pauling scale and a standard atomic weight of 95.96 g/mol. It does not visibly react with oxygen or water at room temperature, and the bulk oxidation occurs at temperatures above 600 °C, resulting in molybdenum trioxide: 2 Mo + 3 O2 → 2 MoO3

The trioxide is volatile and sublimates at high temperatures. This prevents formation of a continuous protective oxide layer, which would stop the bulk oxidation of metal. Molybdenum has several oxidation states, the most stable being +4 and +6 (bolded in the table). The chemistry and the compounds show more similarity to those of tungsten than that of chromium. An example is the instability of molybdenum(III) and tungsten(III) compounds as compared with the stability of the chromium(III) compounds. The highest oxidation state is common in the molybdenum(VI) oxide (MoO3), whereas the normal sulfur compound is molybdenum disulfide MoS2.

ammonium molybdate

Molybdenum(VI) oxide is soluble in strong alkaline water, forming molybdates (MoO42−). Molybdates are weaker oxidants than chromates, but they show a similar tendency to form complex oxyanions by condensation at lower pH values, such as [Mo7O24]6− and [Mo8O26]4−. Polymolybdates can incorporate other ions into their structure, forming polyoxometalates. The dark-blue phosphorus-containing heteropolymolybdate P[Mo12O40]3− is used for the spectroscopic detection of phosphorus. The broad range of oxidation states of molybdenum is reflected in various molybdenum chlorides:

 

Molybdenum(II) chloride MoCl2 (yellow solid)

Molybdenum(IV) chloride MoCl4 (black solid)Molybdenum(III) chloride MoCl3 (dark red solid)

Molybdenum(V) chloride MoCl5 (dark green solid)

Molybdenum(VI) chloride MoCl6 (brown solid)

 

The structure of the MoCl2 is composed of Mo6Cl84+ clusters with four chloride ions to compensate the charge. Like chromium and some other transition metals, molybdenum is able to form quadruple bonds, such as in Mo2(CH3COO)4. This compound can be transformed into Mo2Cl84−, which also has a quadruple bond. The oxidation state 0 is possible with carbon monoxide as ligand, such as in molybdenum hexacarbonyl, Mo(CO)6.

Ferromolybdenum Processing

The ferromolybdenum implies an alloy of 50 to 75 wt % molybdenum and remaining iron, which is mainly used to add molybdenum during a steel-making process.

Generally, the ferromolybdenum is manufactured by a metallothermic reduction (Thermit) method that mixes molybdenum oxide (MoO3) and iron oxide with a strong reducing agent, i.e., aluminum, and then reacts them. 

Ferromolybdenum

The metallothermic reduction method instantly generates a large amount of heat while oxidizing the aluminum by depriving oxygen from the molybdenum oxide or the iron oxide, such that the reaction temperature reaches a high temperature of 3000° C. or higher.

In this case, when copper is included in a raw material, the copper is also reduced and thus, most of the copper exists in the metal, i.e, the ferromolybdenum alloy layer rather than in the oxide slag. Therefore, the copper content of the molybdenum oxide that is a raw material is strictly restricted.