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The corrosion rate of hydrofluoric acid on metals has no fixed value and will vary greatly depending on concentration, temperature, and metal type. The core rules are as follows: Differences in basic corrosion rates of different metals. Antimony, bismuth, cadmium, silver, etc. are high corrosion rate metals. They dissolve very quickly in anhydrous hydrofluoric acid and fall into the intolerable category. International academics. The average corrosion rates of 15CrMoG and 20G carbon steel in a 0.2% gaseous hydrofluoric acid environment at 550°C are 0.0177 mg/(cm²·h) and 0.0125 mg/(cm²·h) respectively. Monel, platinum, and nickel are metals with low to medium corrosion rates. After adding trace amounts of water to anhydrous hydrofluoric acid, the corrosion rate can be reduced by up to 98%. The effect of concentration on corrosion rate. Concentrated hydrofluoric acid with a concentration higher than 85% has a low degree of ionization and has an extremely slow corrosion rate on carbon steel. ； The corrosion rate reaches the peak in the concentration range of 20%~60% ； As the concentration decreases further, the corrosion rate slows down as the conductivity decreases. Effect of temperature on corrosion rate: The increase in temperature will significantly accelerate the corrosion reaction. When the temperature of carbon steel exceeds 65°C, the surface iron fluoride protective film will directly peel off, and the corrosion rate will increase sharply, which is much higher than the value under normal temperature conditions.