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Niobium

Niobium - Melting Point. Melting point of Niobium is 2477°C. The melting point of a substance is the temperature at which this phase change occurs. ... Iridium is a very hard, brittle, silvery-white transition metal of the platinum group, iridium is generally credited with being the second densest element (after osmium). It is also the most ...

Platinum on Niobium and Titanium | Products Finishing

Rinse thoroughly but quickly. Platinum plate using an ammoniacal plating bath. The same reference (available on Amazon) also gives a procedure for plating on titanium: Clean. Thoroughly rinse. Pickle in a solution of hydrofluoric/nitric acid (25/75%) solution until red fumes are evolved. This step requires extreme caution.

Critical mineral resources of the United States—Economic …

In addition, production of many mineral commodities has become concentrated in relatively few countries (for example, tungsten, rare-earth elements, and antimony in China; niobium in Brazil; and platinum-group elements in South Africa and Russia), thus increasing the risk for supply disruption owing to political, social, or other factors.

Rare Metals Background

The critical rare metals (RMs) and metalloids discussed in this section are niobium, tantalum, cobalt, indium, zirconium, gallium, and lithium. Most of these elements are mined in substantial quantities that meet world demand. However, the few countries that possess economically viable sources of critical elements are also experiencing booms in ...

Platinum-Group Metals Statistics and Information

The catalytic properties of the six platinum group metals (PGM)– iridium, osmium, palladium, platinum, rhodium, and ruthenium – are outstanding. Platinum's wear and tarnish resistance characteristics are well suited for making fine jewelry. Other distinctive properties include resistance to chemical attack, excellent high-temperature ...

Platinum group metal-free NiMo hydrogen oxidation …

We introduce a new platinum group metal-free (PGM-free) hydrogen oxidation electrocatalyst with superior performance in anodes of alkaline exchange membrane fuel cells (AEMFCs). A carbon-supported bimetallic nickel–molybdenum catalyst was synthesized by thermal reduction of transition metal precursors on the surface of a …

Niobium: rare and valuable | Anglo American

Niobium is a rare metal found in numerous locations around the world in rocks of volcanic origin. It is relatively difficult to find and is produced from pyrochlore and tantalite ores, and as a by-product of mining for other minerals. The Boa Vista Fresh Rock (BVFR) project, at our Boa Vista mine in Catalão and processing plant in Ouvidor ...

Refractory Metals, Platinum Group Metals and Ceramics by …

Refractory Metals, Platinum Group Metals and Ceramics by Ultramet. Refractory metals are those metals on the periodic table that possess high melting points. At elevated temperatures, refractory metals have excellent mechanical properties.

Minerals, Critical Minerals, and the U.S. Economy

manganese, niobium, platinum group metals, rare earth elements, tantalum, titanium, and vanadium (Figure 3). This list should NOT be construed as a comprehensive list of …

High Temperature Mechanical Properties of the Platinum Group …

There is a constantly increasing need for metallic materials with melting points over 1700°C for use at very high temperatures. In contrast to the refractory metals: tantalum, niobium, tungsten, molybdenum and rhenium, which also have very high melting points, the metals of the platinum group, particularly platinum, rhodium and iridium, are characterised by …

Noble metal

Meaning and history. While lists of noble metals can differ, they tend to cluster around the six platinum group metals (ruthenium, rhodium, palladium, osmium, iridium, platinum) plus gold.. In addition to this term's function as a compound noun, there are circumstances where noble is used as an adjective for the noun metal.A galvanic series is a hierarchy …

Aspects of the platinum group metals (PGM)

Aspects of the platinum group metals (PGM) The PGM iridium, osmium, palladium, platinum, rhodium, and ruthenium are ... Niobium 41 (99) Tc Technetium 43 101.1 Ru Ruthenium 44 102.9 Rh Rhodium 45 106.4 Pd Palladium 46 107.9 Ag Silver 47 112.4 Cd Cadmium 48 138.9 La Lanthanum 57 178.5 Hf Hafnium 72 181.0 Ta Tantalum 73

Global Dynamics and Reflections on Critical Minerals

niobium, platinum group metals, tantalum, titanium and vanadium are recognized by 5 major economies, accounting for 22.2%. Seven critical minerals such as aluminum, beryllium, bismuth, manganese, scandium, tin and zirconium are listed by 4 major economies, accounting for 13.0%. Ten critical minerals such as

Niobium: rare and valuable | Anglo American

Niobium is a rare metal found in numerous locations around the world in rocks of volcanic origin. It is relatively difficult to find and is produced from pyrochlore and tantalite ores, and as a by-product of …

Niobium and tantalum in minerals: Siderophile, chalcophile …

The absence of other platinum-group elements and of niobium in the Ru–Ta alloy is noteworthy, especially as it coexists with inclusions of an alloy of Fe–Sn–Nb–W–Ta in tantalcarbide (Jedwab et al., 1992).

Platinum

Platinum is a member of the platinum group of elements and group 10 of the periodic table of elements. It has six naturally occurring isotopes. It is one of the rarer elements in Earth's crust, with an average abundance of …

Laser and electron beam processing of electrodes consisting …

The present authors succeeded in preparing elec- trocatalytically active amorphous Ni-Nb alloys con- taining small amounts of platinum-group metals covering the surface of corrosion-resistant niobium metal by CO2 laser processing for specimens consist- ing of the bulk niobium substrate on which nickel and platinum-group metals …

Critical Minerals and Materials Program | netl.doe.gov

  1. Executive Order 13817, A Federal Strategy to Ensure Secure and Reliable Supplies of Critical Minerals, December 20, 2017. List of Critical Minerals posted in Federal Register/Vol. 83, No. 97/Friday...
  2. Executive Order 13953, Threat to the Domestic Supply Chain From Reliance on Critical Minerals From Foreign Adversaries and Supporting the Domestic Mining and Processing Ind…
  1. Executive Order 13817, A Federal Strategy to Ensure Secure and Reliable Supplies of Critical Minerals, December 20, 2017. List of Critical Minerals posted in Federal Register/Vol. 83, No. 97/Friday...
  2. Executive Order 13953, Threat to the Domestic Supply Chain From Reliance on Critical Minerals From Foreign Adversaries and Supporting the Domestic Mining and Processing Industries, September 30, 2020.
  3. United States Department of Energy Report to Congress. Report on Rare Earth Elements from Coal and Coal Byproducts, (2017). (https://%20-...
  4. U.S. Coal - Finkelman, R.B., Trace and Minor Elements in Coal, in Organic Geochemistry: P…
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Interdiffusion of the platinum-group metals in nickel at …

Summary and conclusions. Interdiffusion of the platinum group metals Ir, Pd, Pt, Rh and Ru with nominally pure nickel at temperatures of 900, 1000, 1100, 1200 and 1300 °C in fcc (A1) γ-Ni has been characterised, and values of the interdiffusion coefficients determined. Diffusion in these systems gave planar interfaces and no Kirkendall ...

Easy alloying on flat carbides | Nature Catalysis

The team focused on a platinum nanoparticle catalyst supported on a niobium- and carbon-containing MXene, Nb 2 CT x, where T represents functional groups such as –O, –OH and F (Fig. 1a).

Niobium & Niobium Alloys

What is Niobium? Niobium is a ... Platinum and Platinum Group Metals. Platinum (Pt) is a naturally occurring white precious metal, which has always been regarded as one of the most precious metals. Platinum (density: 21.43g/cm3, melting point: 1773°C) is more dense and has a higher melting point than gold, but the output is only 1/20 of that ...

Optimization of a dissimilar platinum to niobium …

Here, a case study of biocompatible metals platinum and niobium using advanced analytical techniques is presented. It describes the variation of properties and microstructure using microresistance spot welding under four conditions, including a legacy process and processing conditions optimized by design of experiments.

Laser-processed electrodes consisting of amorphous nickel-niobium …

Laser processing was applied to a specimen composed of a bulk niobium substrate covered by electrodeposited nickel and platinum group metals in order to form amorphous surface alloys having excellent electrocatalytic activities. The bulk niobium substrate acts as an electric conductor instead of thin amorphous alloys of a high electric resistance. …

Niobium

Founded in 1955 in Araxá, Minas Gerais, Brazil, CBMM has been recognized as the world's largest and leading niobium producer. With more than 70% of the world's niobium reserves, CBMM operates the largest and highest-grade niobium mine with the longest mine life for over 100 years based on the current production plan and lowest cash cost.

Optimization of a dissimilar platinum to niobium

The platinum to niobium cross-wire resistance weld studied was improved by reversing the electrode polarity, decreasing the welding current, duration, and electrode force. Welding niobium with a lower surface roughness did not appear to have a large effect on the output other than a qualitatively more uniform weld, making wire surface …

Group 5 element

Group 5 is a group of elements in the periodic table.Group 5 contains vanadium (V), niobium (Nb), tantalum (Ta) and dubnium (Db). This group lies in the d-block of the periodic table. This group is sometimes called the vanadium group or vanadium family after its lightest member; however, the group itself has not acquired a trivial name …

Platinum group

The platinum-group metals (PGMs), also known as the platinoids, platinides, platidises, platinum group, platinum metals, platinum family or platinum-group elements (PGEs), are six noble, precious metallic elements clustered together in the periodic table.These elements are all transition metals in the d-block (groups 8, 9, and 10, periods 5 and 6).. …

Niobium | Properties, Uses, & History of the Chemical Element

Niobium, chemical element, refractory metal of Group 5 (Vb) of the periodic table, used in alloys, tools and dies, and superconductive magnets. Niobium is closely associated with tantalum in ores and in properties. ... The pure metal is soft and ductile; it looks like steel or, when polished, like platinum. Although it has excellent corrosion ...

GIS for focus areas of potential domestic resources of 11 …

These geospatial data provide the locations of focus areas to be used for the planning and collection of geophysical, geological, and topographic (lidar) data …

Nickel–molybdenum–niobium metallic glass for …

Here we report nickel–molybdenum–niobium metallic glasses as PGM-free HOR catalysts. The optimal Ni52Mo13Nb35 metallic glass exhibits an intrinsic exchange current density of 0.35 mA cm−2 ...