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Flame hardening

Surface hardening process where the workpiece surface is rapidly heated using a gas flame and instantly quenched with a water spray.

In flame hardening, you heat the workpiece surface selectively to hardening temperature with the gas flame. Immediately after, you quench the area with water to harden the surface. The core remains soft and tough, giving a good combination of wear resistance and fracture safety. If you cool too slowly or unevenly, hardness becomes irregular and cracks can form. Make sure the flame moves evenly over the surface and the water hits the hot spot cleanly and forcefully.

MetallurgieSchweißtechnik

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