ASTM A967 PDF

The treatments are the following: immersion treatment using nitric acid solutions, immersion treatment using citric acid solution, and electrochemical treatment. Immediately after the removal from the passivating solution, the parts shall be thoroughly rinsed, using stagnant, countercurrent, or spray washes, singly or in combination, with or without a separate chemical treatment for neutralization of the passivation media. The chemical reactions of the passivating media on the surface of the stainless steel shall be stopped by rinsing of the stainless steel part, with or without a separate neutralization treatment. A chemical treatment shall be applied which will accelerate the formation of the passive film on a chemically clean stainless steel surface. The passivated parts shall exhibit a chemically clean surface and shall, on visual inspection, show no etching, pitting, or frosting.

Author:Daishakar Voodoogal
Country:Libya
Language:English (Spanish)
Genre:Literature
Published (Last):17 June 2019
Pages:95
PDF File Size:1.5 Mb
ePub File Size:20.60 Mb
ISBN:652-5-98683-579-1
Downloads:40801
Price:Free* [*Free Regsitration Required]
Uploader:Akimuro



Contact us today for a customized solution. Call or fill out the form below! ASTM A This is the standard used by general industries to describe and control the passivation of stainless steel.

Passivation is a process of making stainless steel more stainless than it would be if left alone. It is based on using an acid nitric or citric under highly controlled conditions to remove free iron particles from the surface and to help form a metal oxide layer that increases its ability to resist rusting.

It is important to understand that passivation is not a coating applied to the surface; it is a process that makes the surface itself more resistant to staining or rusting. The current and previous versions describe the process and the specific parameters when using nitric acid or citric acid. Each acid has several specific combinations of concentration, temperature, and required time as well as other specific requirements.

Both versions also describe a number of different tests that can be used to determine the effectiveness of the process. The first difference is the addition of a new test that can be used instead of any of the current tests which are continued. The new test is a boiling water immersion test. In addition to this new test, there are slight modifications to several of the existing tests.

The second difference is that the copper sulfate test can now be applied to parts used in food processing. The third important difference is in appendix X1 which states that restrictions on certain high-strength grades such as C that are subject to hydrogen embrittlement are limited to nitric acid and these restrictions do not apply to citric acid passivation.

The fourth significant difference is the addition of Appendix X2 which serves as a general guide for the selection of a passivation treatment for different grades of stainless steel. The new version clarifies a number of specific details, adds an additional new test, removes restrictions on testing parts used in food processing, clarifies restrictions applying to high-strength steels subject to hydrogen embrittlement and adds clarifying information in the new addendum X2.

AMS This is a standard used by the aerospace industry to describe and control the passivation of stainless steel. Passivation is a process of making stainless steel more stainless rust-resistant then it would be if left alone. It is not a coating and does not change any dimensions of a part. It is based on using an acid nitric or citric under highly controlled conditions to remove free iron particles and other impurities from the surface and to help form a stronger metal oxide layer that increases its ability to resist rusting.

In the current version, either method can be used. Section 3. The last significant change removes appendix A, which described certain test methods that were used only when specified by the purchaser. In summary, both standards describe and control how stainless steel corrosion-resistant steel can be made more stainless or corrosion resistant, thereby allowing products to work in harsh conditions, to work longer and to be more reliable than they otherwise would be.

To learn more about the innovative passivation services RP Abrasives provides, including citric acid passivation, contact us today or request a quote below.

EMFISEMA SUBKUTIS ADALAH PDF

Passivation of Stainless Steel

Contact us today for a customized solution. Call or fill out the form below! ASTM A This is the standard used by general industries to describe and control the passivation of stainless steel. Passivation is a process of making stainless steel more stainless than it would be if left alone. It is based on using an acid nitric or citric under highly controlled conditions to remove free iron particles from the surface and to help form a metal oxide layer that increases its ability to resist rusting. It is important to understand that passivation is not a coating applied to the surface; it is a process that makes the surface itself more resistant to staining or rusting.

AAGO JOURNAL PDF

ASTM A967 Chemical Passivation Treatment for Stainless Steel

More A The treatments are the following: immersion treatment using nitric acid solutions, immersion treatment using citric acid solution, and electrochemical treatment. Immediately after the removal from the passivating solution, the parts shall be thoroughly rinsed, using stagnant, countercurrent, or spray washes, singly or in combination, with or without a separate chemical treatment for neutralization of the passivation media. The chemical reactions of the passivating media on the surface of the stainless steel shall be stopped by rinsing of the stainless steel part, with or without a separate neutralization treatment. A chemical treatment shall be applied which will accelerate the formation of the passive film on a chemically clean stainless steel surface. The passivated parts shall exhibit a chemically clean surface and shall, on visual inspection, show no etching, pitting, or frosting. The following tests shall be performed on each lot of stainless steel parts: water immersion test, high humidity test, salt spray test, copper sulfate test, and potassium ferricyanide-nitric acid test.

Related Articles