Conclusions
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1.
The plasma heating process of 9KhF steel provides obtaining of hardened surface cases with a martensitic structure. The depth of the hardened cases with a microhardness of more than 800 H may reach 1 mm.
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2.
The depth of the hardened case changes proportionally to the parameter P/(dnP)0.4, where P is the arc power, dn is the diameter of the plasmatron delivery nozzle, and v is the rate of movement of the plasmatron.
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3.
The thermal efficiency of the plasma-hardening process of 9KhF steel is 25–30% with the use of argon as the plasma-forming gas. With operation of the gun with a mixture of Ar+70% N2 the thermal efficiency decreases to 9–10%.
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Additional information
Institute of Problems of the Technology of Microelectronics and Special Purity Materials, Academy of Sciences of the USSR. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 11, pp. 13–17, November, 1989.
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Kraposhin, V.S., Bobrov, A.V. & Gaponenko, O.S. Surface hardening of 9KhF steel by heating with a plasma gun. Met Sci Heat Treat 31, 816–821 (1989). https://doi.org/10.1007/BF00795563
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DOI: https://doi.org/10.1007/BF00795563