SOME OF APPLICATIONS OF IRIDIUM METAL NANOPOWDER

Highly pure iridium nanopowder is intended for production of high quality industrial iridium products, structural alloys, development of new materials with pre-determined set of physical and chemical characteristics.

 

1. Production of iridium crucibles

Application of highly plastic solids based on MNPI enables for simplifying the manufacturing process and obtaining crucibles without welded joints.

Suggested variant of crucible manufacturing procedure using MNPI ensures the following:

  • Exclusion of expensive equipment for EBR and growing of iridium monocrystal.
  • Increasing of metal output into the finished product by 1,5 times.
  • Shortening of manufacturing cycle by several times.
  • Considerable decreasing of iridium irrecoverable losses.
  • Decreasing of cost of production by 1,5-2 times.
  • Integration with standard procedure at forging stage. 


2. Production of toxic gas sensors for atmosphere analysis

            International practice for production of hydrogen sulphide gauge sensors suggests using of iridium or platinum black as electrochemical component. Iridium and platinum black is characterized with high chemical activity and highly flammable in air. All process operations with it are made in special boxes with inert atmosphere.

            In order to exclude risk of self-ignition during transporting the manufacturer has to oxidize it. This operation is almost uncontrollable and that is why the oxidation level varies within wide range. Thus, iridium black produced by other companies has standard range of oxidized metal 18-60% and varies from batch to batch. Due to this fact, when using next batch one needs to choose dosage of black application to sensor membrane, which entails rejection of a number of sensors. Secondly, oxidized part of iridium does not participate in generation of sensor electrical signal and represents expensive ballast.


           Results of testing for MNPI as a component of gas sensor electrode material performed at the enterprises manufacturing gas analytical equipment Analitkhimavtomatika, LLC, Moscow and INFORMANALITIKA, LLC, St. Petersburg verified decrease of catalyst flow rate by 3 times without deterioration of technical properties of sensor. Simultaneously all process operations of sensor production were performed in air atmosphere without using of insulating machines. In addition to cheapening of production, application of MNPI enables to exclude using foreign supplies of iridium and platinum black.

3. Production of seamless tubular billets

In the USA are currently developing procedures to apply iridium to the products operated in severe conditions, in particular, to rocket nozzles. Application of high temperature resistant anti- corrosion coating to working face of combustion chamber and rocket motor nozzle ensures temperature rise from 1300°C (produced motors) to 2000-2100°C and thus increases efficiency of fuel consumption and effective load.

In order to attain this goal they chose chemical vapor deposition (CVD) method with application of complex iridium organic compounds. These organometallic compounds are expensive to produce and require special conditions for synthesis, and vapor phase process with application of these compounds is hard to localize in application area. That is why 70-80% of iridium gets assimilated by chamber walls and only 20-30% at the outer surface.

MNPI application allows production of seamless tubular billets with iridium, which is processed by hot rolling to the needed dimensions of rocket insert. The workpieces possess nanostructure, which enables rolling at relatively low temperature.

4. Production of disks, pellets and targets of various dimensions

There are strict requirements to iridium disks for production of radioactive nuclides with regard to geometrical dimensions, roughness and absence of edge spalling, because the latter causes serious environmental issues due to pollution of process equipment and environment. These requirements are fulfilled by using fine-grain iridium. Alloying additions are added to industrial iridium for grain refining, as: rhenium (3%), ruthenium (2%) in Russian technology, and wolframium (0,3%) in the rest of Europe and USA. However adding of alloying additions decreases iridium content and deteriorates consumer parameters.

Application of MNPI at manufacturing of these products ensures availability of fine-grain crystal structure excluding extra costs for alloy addition and increases lifetime of radiation source.

5. Production of reference standard

MNPI high thermal stability and dispersity provides capability to use it as nanometric standard in metrology and for production of powdered reference standard of spectrum analysis. In the last case MNPI application is preferred as in existing methods for reference standard production they use powder with dispersity 10-50 μm, to produce it one needs expensive equipment and extra costs. MNPI provides high chemical purity and homogeneity of reference standard.

There are good prospects to use MNPI as catalytic agent in fuel cells and in organic synthesis, at production of metal and ceramic-metal compounds.

Anthropogenic and industrial wastes with iridium content over 40% can be used as raw material for MNPI production.

As of today iridium material of this quality is absent at the local and international market which ensures unquestionable competitive advantages of this