Strong erosion: the metal workpieces dip in with high and certain temperature erosion of solution, to remove metal workpieces surface oxides and corrosion things process.

强浸蚀：将金属制件浸在较高浓度和一定温度的浸蚀溶液中，以除去金属制件表面上氧化物和锈蚀物的过程。

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Weak erosion before plating, in a certain: remove metal parts in the solution of surface extremely thin oxidation film, and make the process of surface activation.

弱浸蚀：电镀前，在一定组成溶液中除去金属制件表面极薄的氧化膜，并使表面活化的过程。

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Hydrogen brittleness: because, in addition to the erosion oil or plating process such as metal and alloy hydrogen atom absorption and cause brittle.

氢脆：由于浸蚀，除油或电镀等过程中金属或合金吸收氢原子而引起的脆性。

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Such concentrations are usually created by geological events, such as volcanic eruptions and tectonic plate shifts that steer hot metal-bearing fluids into upper, accessible parts of the Earth's crust, erosion, or massive sedimentary movements.

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