Process for steam conversion coating aluminum

Metal treatment – Process of modifying or maintaining internal physical... – Processes of coating utilizing a reactive composition which...

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

148285, C23C 810

Patent

active

054964172

ABSTRACT:
A conversion coating process for pretreating an aluminum or aluminum alloy surface in order to increase overlying coating adhesion and diminish corrosion and abrasion. The process involves delivering a flow of pure steam produced from deionized feedwater into a chamber. The flow of pure steam is directed against a baffle within the chamber causing the flow to diffuse. That is, the flow of steam is diverted from its initial direction of travel and caused to swirl. The surface of the aluminum or aluminum alloy metal is subjected to the swirling flow of pure steam so as to generate an oxide layer on the metal. The swirling pure steam subjects the resulting oxide layer to a pressure across its face which prevents the crystallization of the oxide layer in a defined and orderly pattern. The workpiece surface is preferably preheated to a threshold temperature prior to delivering the steam. In an alternate embodiment, the swirled flow of steam is circulated through the chamber and out of an exit port so as to maintain a non-static flow environment. The flow of steam exits the exit port and contacts the workpiece surface so as to generate the oxide layer. The process can be used as an intermediate step in a multi-step conversion coating process. The resulting aluminum-oxide film has superior work-environment performance and a high quality finish without any associated health or environmental risks. The process is designed to comply with U.S. military specification MIL-C-5541.

REFERENCES:
patent: 3247026 (1966-04-01), Switzer et al.
patent: 3964936 (1976-06-01), Das
patent: 4149912 (1979-04-01), Craighead et al.
patent: 4711667 (1987-12-01), Bibber
patent: 4759805 (1988-07-01), Saruwatari
Interim Report, Aug. 18, 1992, Non-Chromated Surface Pretreated For Aluminum, Report No. NADC-92077-60.
Phase Report, Jun. 24, 1992, Naval Air Warfare Center, Aircraft Division at Warminster Environmental Materials Program--Phase 1, Report No. NAWCADWAR-92075-60.
Military Specification, Jun. 30, 1970, Chemical Conversion Materials For Coating Aluminum and Aluminum Alloys, MIL-C-81706.
Military Specification, Nov. 30, 1990, Chemical Conversion Coatings on Aluminum and Aluminum Alloys, MIL-C-5541E.
Pharmaceutical Technology, Dec. 1982, Clean Steam in the Pharmaceutical Plant, Howard A. Forster and V., Kumar Gupta.
Stainless Steels for Bioprocessing, Part 3: Corrosion Phenomena, C. P. Dillon, D. W. Rahoi, and A. H. Tuthill.
BioPharm, Jun. 1990, "Rouge" and Its Removal from High-Purity Water Systems, Gopi R. Menon.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Process for steam conversion coating aluminum does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Process for steam conversion coating aluminum, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for steam conversion coating aluminum will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-1410202

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.