Contaminant-Free Steel

materials and coatings
Contaminant-Free Steel (LEW-TOPS-123)
Superior steel alloys for high performance applications subject to rolling contact fatigue
Innovators at NASA's Glenn Research Center have devised a method for creating ultra-pure steel alloys that are free from ceramic particle contamination. These ultra-high-quality steels can be used to make bearings, gears, or any other machine components. Conventional steel alloys contain small, unwanted amounts of hard particle inclusions - or dirt - that cause weak points in the steel, making components vulnerable to failure. Such flaws act as locations for stress concentration and can form initiation sites for catastrophic fracture in mechanical parts. Glenn's newly developed process for creating steel alloys has proven to be nearly perfect, with the potential for significantly better performance than conventional steels, especially in high-stress cycle applications like rolling element bearings. These extremely clean steels are ideal for any application where unwanted contaminant inclusions stand in the way of high reliability and long-life under high load and speed operation.

The Technology
For many highly stressed engineering applications like bearings and gears, contaminated steel parts can lead to devastating outcomes such as an emergency shutdown or the end of a mission. Ensuring that these critical components are as homogeneous as possible and free from porosity and other flaws is vital to performance, yet conventional steelmaking processes have multiple pathways of entry for unwanted contamination. The conventional process typically begins with uncleaned, dirty scrap steel. Subsequent processing steps involve ceramic-lined crucibles, ceramic-lined piping, and brick-lined furnaces and crucibles, any one of which can introduce further contamination. Although modern steel makers use various purification steps to remove impurities, some particle inclusions inevitably make their way into the final product. In contrast, Glenn's innovative method starts with only elementally pure (at least 99.99% pure) ingredients and ceramic-free melting processes followed by ceramic-free atomization and powder metallurgy techniques. First, the elementally pure steel constituents are melted inside a water-cooled, copper crucible "plasma hearth furnace" vacuum chamber. The melted steel is then solidified inside the copper crucible to form an absolutely pure ingot. This ingot is then atomized into pure powder using an electrode induction gas atomizer. The resulting powder is placed into a clean steel can that is hot isostatic pressed into a pure, fine-grained ingot of steel. At no point in the process does the steel or its ingredients come into contact with any non-metal or ceramic materials. Furthermore, the steel is never exposed to air or oxygen at high temperatures (which could lead to oxide inclusions). Glenn's method, which can be used to generate any high purity steel alloy, advances state-of-the-art steel production by creating a vastly superior and highly reliable product.
Space Satellite An ultra-clean M62 high-carbide tool steel core encased in mild steel can be used for the hot isostatic press process
  • Ultra Clean: Uses elementally pure ingredients, ceramic-free melting processes, ceramic-free atomization, and powder metallurgy processes to avoid unwanted contaminants
  • Highly Reliable: Produces extremely clean parts that are capable of long-life when used in applications with high mechanical stress
  • Fatigue-Resistant: Free from large hard inclusions that can cause the formation of pits and cracks on metallic surfaces
  • Proven: Modeled after the same well-developed processes used to generate ultra-pure nickel titanium (or NiTi) alloys in NASA missions
  • Flexible: Useful in the production of multiple types of high-purity steel alloys, including high-carbide M62 and NiTi

  • Contaminant-free steel manufacturing
  • Rolling element bearings
  • Gears
  • Aerospace
  • Tooling and cutting
  • Medical equipment
  • Satellite mechanisms
  • Helicopters
  • Nuclear power plants
  • Oil and gas drilling
Technology Details

materials and coatings
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