2009 - PANart Patents 2009- nitriding recipe
Last Updated on 11. December 2021
PANArt Patent about nitriding recipe: „Method for production of a metallic-sounding musical instrument“ in EU and USA.
Source: https://www.hangblog.org/patents-trademarks-designs/
Patent description: „In the method the steel sheet with a thickness of 0.75 to 1.25 mm required for the production is nitrided until the sheet is completely permeated with iron nitride needles. The linear density of the needles is, as a rule, between 401010.sup.3 m.sup.-1 to 8010.sup.3 m.sup.“
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