Blackening treatment: Blackening treatment produces a black oxide layer mainly by reacting with chemical reactants. It is mainly carried out using sodium hydroxide and sodium nitrite at 135-145 degrees Celsius and is more alkaline.
Author: Anna
Differences between phosphating and blackening
1. Top Waterjet Cutting Machine Cutter Head Assembly: Blackening treatment produces a black oxide layer mainly by reacting with chemical reactants. It is mainly carried out using sodium hydroxide and sodium nitrite at 135-145 degrees Celsius and is more alkaline.
2. Phosphating treatment: Phosphating treatment, on the other hand, involves placing the metal workpiece into a phosphate solution to form a phosphate cover layer through a chemical reaction. The main components include phosphoric acid and primary salts such as zinc, calcium, manganese, etc., and the treatment temperature ranges from 5-95 degrees.
1. Blackening treatment: the oxide layer formed by blackening treatment has poor corrosion resistance and is prone to rusting.
2. Phosphating treatment: the phosphate protective layer formed by phosphating treatment has better corrosion resistance, especially after applying rust preventive oil, its corrosion resistance is 10-20 times higher than that of blackening treatment.
1. Blackening treatment: mainly used for occasions with requirements on surface color, such as high-grade furniture, toys, stationery, watches and so on.
2. Phosphating treatment: It is applicable to the occasions with high requirements for corrosion resistance, hardness and abrasion resistance, such as automobiles, motorcycles, transmission parts and so on.