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535A99 - 1% Chromium-Molybdenum High Carbon Through Hardening Steel

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535A99 grade steel is a high carbon alloy steel commonly supplied in the spherodised annealed condition.

Following machining it is subsequently hardened and lightly tempered to give parts a high surface hardness with a deeper hardened zone than can be obtained with case hardening steels.

It can be oil quenched in sections up to 1” diameter and water hardened in larger sections, then subsequently tempered to produce a very hard wear resistance surface in excess of 65HRc.

Size Range

38mm - 235mm Dia

Typical applications of 535A99 grade steel

  • Ball and roller bearings
  • Bearing rings
  • Connecting rod
  • Big end bushes
  • Lathe centres
  • Collets
  • Cams and pawls
  • Small hardened steel cold work rolls
  • Blanking and forming tools
  • Punches
  • Knurling tools
  • Gauges
  • Fuel nozzles
  • Shear blades
  • Bullet cores
  • Instrument pivots
  • Spindles

535A99 steel is still often referred to as EN31 steel - its equivalent grade under the previous BS 970: 1955 standard.

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