1. IntroductionAustenitic stainless-steel has excellent rust resistance and great cold and also hot working efficiency, so it is widely made use of to make numerous type of get rid of anti-corrosion demands. The passive film externally of austenitic stainless steel has a great influence on its deterioration resistance. The passive movie of austenitic stainless-steel is mainly obtained by pickling and passivation.2. FormulaPickling remedy: 20% nitric acid + 5% hydrofluoric acid + 75% waterPassivation service: 5% nitric acid + 2% potassium dichromate + 93% waterMarinading passivation service (2 in one): 20% nitric acid + 10% hydrofluoric acid + 70% water3. https://sleettuna94.gumroad.com/p/evaluation-of-peeled-off-trouble-for-electro-plating-and-also-powder-layer-parts . Pretreatment:Get rid of the oxide layer by Shot blasting.Tidy welding places on both sides, get rid of oil and also other spots externally with gasoline or cleaning agent.Hefty oil to be cleaned with 3-5% alkali cleaning option. After cleaning, cleanse the surface with tidy water.b. Pickling as well as passivation.Marinading as well as passivation (2 in one) remedy can complete pickling and also passivation at once. The temperature as well as time will be purely controlled. If the temperature is reduced, the moment will certainly be long, and also if the temperature is high, the time will be short. Protect against matrix corrosion brought on by failure to attain pickling effect or excessive pickling. After therapy, it should be thoroughly washed with clean water to make the surface area free of residual liquid, so regarding promote subsequent passivation treatment. |