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QPQ Finsih

SBN/QPQSM is a diffusion process that provides distortion-free dimensional stability while hardening the surface of the part (up to three times the strength of carbon steel) thereby producing superior wear resistance, improved fatigue strength, and surface lubricity. Unlike a plating or a coating,SBN/QPQSM adds virtually no dimensions to the part and there is nothing to chip or flake off.

The term “QPQSM,” or Quench-Polish-Quench is based on a sequence of process events that occur directly following the nitrocarburizing cycle that includes a Quench (the nitrocarburizing bath is typically 1075 degrees F) followed by a Polish, then followed by an additional Quench step that produces a layer of iron nitride which adds an element of corrosion protection. The SBN/QPQ process produces a cosmetically appealing, matte black finish.

Some of the most relevant advantages of applying QPQ treatment include:

  • Improved corrosion resistance.

  • Improved wear resistance.

  • Improved fatigue resistance.

  • Improved heat resistance.

  • Reduced friction between moving parts.

  • Better and smoother surface finish.

  • Reduced distortion of the metal structure.

  • Short cycle times.

  • Results are predictable and consistent.

  • Applicable to a wide variety of materials.

  • Applicable to complex pieces.

  • Environmentally friendly.

  • Appealing black surface result.

Several materials can be treated by applying the QPQ coating.

Ferrous materials are the most commonly treated by this process. This is because it is mainly used to improve corrosion resistance.

That said, here are some of the QPQ coating applicable materials:

  • Carbon steels.

  • Stainless steels.

  • Alloy steels.

  • Austenitic steels.

  • High-speed steels.

  • Structural steels.

  • Pure iron.

  • Cast iron.

  • Sintered iron.

Common industries that take the benefits provided by the QPQ treatment include:

  • Automotive

  • Weapons manufacturing.

  • Metal manufacturing.

  • Oil and gas.

  • Construction equipment manufacturing.

  • Food

  • Pharma

  • Chemicals

Therefore, common application examples are:

  • Hydraulic valves.

  • Ejector Pins & Ejector Sleeves for injection mold

  • Piston rods.

  • Manifolds

  • Shock absorbers.

  • Hydraulic jacks.

  • Brake rotors.

  • Camshafts

  • Clutch discs.

  • Gears

  • Pneumatic components.

  • Seals

  • Bushings

  • Bearings

  • Dies

  • Forging tools.

  • Extrusion tools.

  • Drill bits.

  • Milling cutters.

  • Golf club heads.

  • Power tool parts.

  • Electrical switches.

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