"HRF" meaning in English

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  "lang_code": "en",
  "pos": "noun",
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          "word": "hardness on Rockwell scale F"
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        "Abbreviation of hardness on Rockwell scale F."
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          "hardness",
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        "(materials science) Abbreviation of hardness on Rockwell scale F."
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  "word": "HRF"
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  "lang_code": "en",
  "pos": "noun",
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          "word": "hardness on Rockwell scale F"
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        "Abbreviation of hardness on Rockwell scale F."
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      "qualifier": "materials science",
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        "(materials science) Abbreviation of hardness on Rockwell scale F."
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  "word": "HRF"
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