Fed qqp35c was superseded by astm a967 which added citric passivation types to complement the nitric passivation with a less toxic acid. Passivation is designed to remove the small amount of free iron from the visually clean surface. Astm a967 chemical passivation treatment for stainless steel. Requirements per ams 2700b passivation is used to remove. Ams2700 and astm a967 both allow the use either nitric acid or citric acid. Passivate passivation specification stainless steel astma967. When used correctly, citrisurf 2210 meets the requirements of the astm a967, astm a380, astm b600, and ams 2700 standards. Passivation is the removal of free iron particles or iron compounds from the stainless steel surface by means of a chemical dissolution, most typically by a treatment with an acid solution that will remove the surface contamination. Passivation passivation, passivation stainless steel.
Passivate passivation specification stainless steel astm. After testing, speciments shall show no signs of rust or corrosion. Differences between mils5002 type iii and qqp35 type. Federal specification qqp35, astm a967, sae ams qqp35, and ams 2700 description. Passivation of stainless steel astm a967, qqp35, ams 2700.
Citrisurf 8050 stellar solutions stainless steel passivation. Passivation ams 2700, astm a 380, astm a 967 anoplate, inc. Passivation services welcome to scott metal finishing. Amsqqp35 which replaced federal specification qqp35 is an sae standard used in the aerospace industry to passivate stainless steel parts. Lockheed martin lessons learned stainless steel passivation. The electrolizing corporation of ohio passivation process meets astm a96701 and ams qqp35, types 2, 6, 7 and 8. Looking to the reference specs, it seems aerospace applications.
The specification covers the requirements for a process to assure removal of free iron or other less noble contaminants from the surfaces of corrosion resistant steel parts. Qqa35, astm a967, ams 2700 passivate, stainless, steel corrosion resistant. Passivation standards stellar solutions stainless steel. The following specs refer to astm a967 and ams 2700 for passivation of stainless steel. Rp abrasives, also known as rpa, is a new england metal finisher that provides surface and metal finishing requirements for our customers across a variety of industries. These operations can remove the passive oxide layer thereby exposing iron or transferring iron onto the surface. Revision e passivation of corrosion resistant steels nov. Advanced plating technologies, a milwaukee, wisconsin company, is an industry leading provider of passivation of stainless steel to astm a967, ams 2700 and qqp35 specifications, employing both citric and nitric acid methods. The active passivation specifications are ams 2700 and astm.
Passivation is a chemical process whereby soils and trace metallic elements from the machining process are removed from the surface of stainless steel, improving the inherent corrosion resistance of the material. Imagineering finishing technologies is a trusted source for the passivation services of stainless steel. Dod adopted sae ams7881 tungsten carbidecobalt powder, agglomerated and sintered sae ams7882 tungsten carbidecobalt chrome powder, agglomerated and sintered sae ams c8837 coating, cadmium vacuum deposited. We take care in passivating austenitic or low chromium grades of stainless steel. Except, replacement for qqp35 is ams 2700 and not astm a 967. Requirements per ams 2700b passivation is used to remove metallic contaminants from the surface of corrosion resistant steels using chemically oxidizing methods to prevent bulk degradation. Similarly to astm a967, it allows for passivation using either nitric acid or citric acid. Passivation of stainless steel is a process that removes free iron from the surface of a stainless component and at the same time promotes the formation of a thin, dense oxide protective barrier. Citrisurf 2210 is a high quality blend of chemicals formulated for the cleaning. Sae standard for passivation of corrosion resistant steels. It includes recommendations and precautions for descaling, cleaning, and passivation of stainless steel parts. The astm a967a967 replaces astm a967a967m05 which is now obsolete. Ams qqp35 is being canceled in favor of ams 2700 at the moment it is version b you should never ask for standard passivation on imports. Federal specification cancelled in 1997 saeqqp35 ams specification cancelled in 2005 astm a967 saeams2700 cancelled in 1997 saeqqp35 ams specification cancelled in 2005 astm a967 saeams2700.
I dont see a reason to since you will have to passivate after shot peen. Passivation of aerospace stainless steel parts with citric acid solutions. Passivation although stainless steel is known to be a corrosion resistant alloy, it can become reactive after subjected to certain manufacturing applications such as machining or shot peening. The passivation process insures that the naturally occurring, protective oxide film is continuous on the stainless surface. There is a table that lists many types of stainless steel alloys and shows the best passivation type to be used. Passivation is a process of making stainless steel more stainless rustresistant then it would be if left alone. Astm a967 and ams 2700 standards for passivation rp. Ams 2700 revision e just released on passivation of corrosion. Passivation services onsite astm, asme rapid response. Citrisurf 8050 is a high quality blend of chemicals formulated for the derouging, descaling, and passivation of stainless steel products. In this article we will compare nitric vs citric acid passivation which are the two primary chemistries specified in astm a967 and ams 2700. Passivation is the removal of iron or iron oxide from the surface in the passive film or top 3 to 4 molecular layer. Testing water immersion verifies the passivation process on all grades of stainless steel, with exception of 440c. Abrasion or excessive heat caused by welding will destroy this protective layer and expose the metal to corrosion.
Fortheconceptinspacecraft,seepassivation spacecraft. Passivation is the treatment of the surface of corrosionresistant steels i. The other main passivation standard currently active, used in the aerospace industry, is ams 2700. Passivation of corrosion resistant steels emirfi shield. It includes several alternative tests, with acceptance criteria, for confirmation of effectiveness of such treatments for stainless steel parts. Passivation precision delicate medicalgrade passivation of medium sized to micro stainless steel, titanium and cobaltchrome medical vapor degreasing. I have drawing document that is specifying ams 2700 type 6 or 7, for both 304ss and 174ph. Whether for aerospace controls, medical implants, marine fasteners, computer components, or a number of other industrial applications, our cleaning processes remove iron or sulfides without stock removal of the substrate alloy, to prevent premature corrosion and enhance the. Yard scale is not acceptable, as neither is heat scale, mill.
This means that dirt, oils, rust, smut, carbon deposits, oxide layers, scale on the stainless steel parts must be removed prior to passivation. Passivationchemistry fortheconceptinnonlinearcontrol,seefeedbackpassivation. B117 practice for operating salt spray fog apparatus. A380 practice for cleaning, descaling, and passivation of stainless steel parts, equipment, and systems. Referenced documents purchase separately the documents listed below are referenced within the subject standard but are not provided as part of the standard astm standards. Astm a967 and ams 2700 standards for passivation rp abrasives. The new edition replaces ams 2700 revision d which was released back in july of this year. We do not recommend passivating stainless steel that has a carbonizednitrided surface, because nitric acid will dissolve the surface and reduce the size of the component. Omni metal finishing processes passivation process type class military specification pasivation pasivation process ams2700 amsqqp35 astm a 967 astm 380.
This covers several different types of chemical passivation treatment for stainless steel parts. Citric acid passivation of citric acid passivation of. Dod adopted sae ams7881 tungsten carbidecobalt powder, agglomerated and sintered sae ams7882 tungsten carbidecobalt chrome powder, agglomerated and sintered sae amsc8837 coating, cadmium vacuum deposited. Stainless steel passivation services from imagineering. Ams2700 astm a967 passivation corrosion engineering. The expertise we offer is clear in our management and senior teams, showcasing over 100 years of combined experience. This is a standard used by the aerospace industry to describe and control the passivation of stainless steel. Passivation, pickling, pickelpassivation applicable specifications. Ams 2700 revision e just released on passivation of. Depending on the type of stainless steel and end application certain passivation processes may perform better at passivating than others. Developing an effective passivation process to maintain. Passivation ams 2700, astm a 380, astm a 967 anoplate. Advance surface technologies provides both nitric and citric passivation treatments on titanium and stainless steel alloys that adhere to qqp35c, amsqqp 35a, ams 2700c, astm a 96705 and astm a 38006 standards.
Citric acid passivation for titanium and titanium alloys is now recognized in the astm standard. Passivation of stainless steel ams 2700e method 1 type 7. I believe that ams 2700 is the passivation spec for stainless steels. A complete list of each of these changes is listed in 8. The active passivation specifications are ams 2700 and. Passivation of stainless steel ams 2700e method 1 type 7 ams 2700e method 1 type 8 ams 2700e method 2 astm a967a967m nitric 3 astm a967a967m nitric 4 astm a967a967m citric 1 astm a967a967m citric 2 astm a967a967m citric 3 astm b91202 anodize on aluminum mila8625 type ii class i mila8625 type ii class ii. Various acids, such as nitric acid, mixed acid, or citric acid are used to. Dec 07, 2011 ams 2700 revision e, passivation of corrosion resistant steels, has just been released. Our practices are recognized as industry best and in compliance with ams 2700 and a967. Citric acid passivation services metal passivation rp. Passivation of aerospace stainless steel parts with citric. The nitric acid treatments are labeled method 1 and given as eight different variations called types, in keeping with the old qqp35. Federal specification qqp35, astm a967, saeams qqp35, and ams 2700 description. Amse is issued to incorporate all changes approved by ams committee.
Whether for aerospace controls, medical implants, marine fasteners, computer components, or a number of other industrial applications, our cleaning processes remove iron or sulfides without stock removal of the substrate alloy, to prevent premature corrosion and. Passivation is the acidic removal of residual iron or other contaminants from the surface of stainless steel. This practice references qqp35 later renumbered ams qqp35 and then withdrawn in favor of ams 2700, another major passivation document. The new edition replaces ams 2700 revision d which was released back in july. Titled standard specification for chemical passivation treatments for stainless steel parts, the new revision is one of our goto documents for chemical passivation. Revision f passivation of corrosion resistant steels march 18, 2018 obsolete revision information. Passivation, pickling, pickel passivation applicable specifications. Sae ams 2700f2018 is purposed with covering guidelines for the passivation process, by which free iron or other less noble contaminants are removed from the surfaces of corrosion resistant steel parts. Derouging uses stronger acids to remove large visible accumulations of iron oxides to a visually clean condition. Therefore ast uses different types of pickling acids designed to remove these films prior to the passivation of the parts. It is not a coating and does not change any dimensions of a part. Specifications ams 2700 rev e, astm a38006, astm a 967, milstd171 fin 5. For worldclass citric acid passivation services, look no further than rp abrasives.
Astm a967a967m 20 edition has just been released and is available from document center inc. Proposed changes by dod activities must be submitted to the dod adopting activity. The electrolizing corporation of ohio passivation process meets astm a96701 and amsqqp35, types 2, 6, 7 and 8. What is astm a967 specification for chemical passivation. Fed qqp35 has much useful information on preparation and passivating stainless steel. Ams 2700 revision e, passivation of corrosion resistant steels, has just been released. Advanced plating technologies, a milwaukee, wisconsin company, is an industry leading provider of passivation of stainless steel to astm a, ams ams qqp qqp passivation of corrosion resistant steels. This surface discoloration can be caused by a number of factors which may include salt air, salt on roads, nearby mild steel cutting or. Amsqqp35 replaced qqp35 ams 2700 astm a380 astm a967 astm b254 astm f86 titanium components mils5002. Ams2700 astm a967 passivation corrosion engineering eng. The formation of this protective layer is called passivation. If allowed to remain the iron corrodes and often gives the appearance of large or small rust spots on the stainless steel. Passivation of corrosion resistant steel in accordance with qqp35, amsqqp35, astm a967, ams 2700 specification classification qqp35 amsqqp35 types ii medium temperature nitric acid solution with sodium dichromate additive.
Ams2700e is issued to incorporate all changes approved by ams committee. Astma967 standard specification for chemical passivation. Differences between mils5002 type iii and qqp35 type vi. In this case the supplier could be an approved a supplier having access to these specs. The active passivation specifications are ams 2700 and astm a967 both allow the use either nitric acid or citric acid. Citrisurf 2210 stellar solutions stainless steel passivation. Like astm a967 did for other industries, the new ams specification allows the use of citric acid passivation in the aerospace industry. Passivation of stainless steel benchtop passivation. Field cleaning and passivation of stainless steel in certain environments, all stainless steel materials can develop surface discoloration. Approved processes sorted by oem hitech metal finishing. Astm a967, astm a380, ams 2700 qqp35, astm a967, astm a380, ams 2700 qqp35, astm a967, astm a380, ams 2700, astm f86 apt specializes in demanding masking and high aesthetic powder paint. Passivation alone will not remove heavy adherent oxide films created from heat treatment, welding, hotforming and other hightemperature operations.
Ams2700e is issued to incorporate all changes approved by ams committee b by 28 day limited scope ballot closed on 6142011 and which were intended to be reflected in ams2700d but some of which were inadvertently omitted. Americas premiere passivation and mechanical metal finishing house. According to my resources, the 304 ss get passivated by hno 3 nitric acid. The part is then passivated per ams 2700, method i, type 2 or 8, class 4, tested with water immersion or high humidity. The metal finishing experts at rp abrasives explain the key aspects of the astm a967 and ams 2700 standards for stainless steel passivation. Im looking for a passivation type for 304ss and 174ph per ams 2700. Our specialties include preparing metal components for final use and applying some of the many sophisticated coatings available today.
Stainless steel is able to resist corrosion thanks to a passive chromium oxide layer that forms on its surface. Passivation is used to improve the surface condition of stainless steel by dissolving the iron that is embedded in the surface by forming, machining, or other manufacturing steps. Federal specification cancelled in 1997 saeqqp35 ams specification cancelled in 2005 astm a967 saeams2700. Developing an effective passivation process to maintain laser. This specification covers several different types of chemical passivation treatments for stainless steel parts. Dicronite southwests citric acid passivation process is widely used in like aviation, space, plastics, medicalpharmaceutical, food processing equipment, automotive, mechanical, semiconductor, and vacuum equipment. Sae ams2700 passivation of corrosion resistant steels. The benchtop ultrasonic citric passivation system processes medical device industry parts with precision part cleaning and passivation after machining and laser mark. Please contact chris barnes for detailed questions conceding any passivation questions you many have.