Manavbasi A.,METALAST International, Inc.
National Association for Surface Finishing Annual Conference and Trade Show 2012, SUR/FIN 2012 | Year: 2012
A novel hexavalent chromate-free conversion coating was developed to improve anti-corrosion and adhesive-bonding characteristics of the magnesium alloys and zinc-nickel (Zn-Ni) plated steel substrates. The corrosion behavior of the coated and uncoated alloys was investigated by Neutral Salt Fog (NSF) and Electrochemical Corrosion tests. Surface wettability of the pretreated substrates was investigated by static contact angle measurements. Wet-tape adhesion tests verified that there is a strong adhesion between the primer and the chem film treated substrates. The morphology and composition of coated surfaces were investigated by Optical Microscopy (OM), Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Spectroscopy (EDX) methods. This trivalent chromium based surface treatment is potential hex-chromate conversion coating replacement for magnesium alloys and Zn-Ni plated steel. Source
Agency: Department of Defense | Branch: Air Force | Program: SBIR | Phase: Phase I | Award Amount: 98.97K | Year: 2009
The European Union''s RoHS and WEE Directives mandated the elimination of the carcinogenic, hexavalent chromium coatings for metals, including magnesium and zinc-nickel plated substrates. The purpose of this project is to find chemistry that will meet requirements of industry performance specifications and of the mandate. METALAST intends to explore trivalent chromium in conjunction with two other components to build a corrosion resistant, adhesive, environmentally-friendly coating for Zn-Ni plated steel and magnesium substrates. METALAST is planning to utilize various techniques for quantitative and qualitative observation of corrosion, surface energy, and other properties that the solutions impart to the substrates. The trivalent chemistry is expected to impart similar anti-corrosion characteristics as the proven, hexavalent chromium technology. The other two components are for increasing the coating thickness and improving thermal stability. Methodology for testing will include EIS, SEM/EDX, OCP, dyne analysis, and chemical dissolution, salt spray, and potentiodynamic polarization testing. In doing so, the objectives for performing the research are to determine which components of the intended formula are most influential to corrosion and adhesive behavior, and at which operating parameters, as well as determine whether the formulas, will meet common specifications of the industry the METALAST intends to pursue upon commercialization. BENEFIT: Military, aerospace, aviation and commercial industries requiring hexavalent chromium on Zinc-Nickel and magnesium alloys would most likely change or alter their respective specifications and require a trivalent chromium product. Most manufacturers who require chromate conversion on their parts will opt for trivalent chromium for compliance purposes.
Agency: Department of Defense | Branch: Air Force | Program: SBIR | Phase: Phase II | Award Amount: 749.86K | Year: 2010
The objective of this Air Force SBIR Phase II proposal is to optimize and develop an environmentally friendly replacement for the carcinogenic hexavalent chromium based conversion coatings on AMS 4434 Magnesium and Zinc-Nickel plated AISI 4130 and 4340 steel substrates. The proposed research is a continuation to the successful studies conducted during the Phase I stage of establishing the feasibility of a new trivalent chromium based conversion coating for the aforementioned alloys. The proposed conversion coating is a formulation of trivalent chromium, zirconium and an organic inhibitor in proportions found to offer effective corrosion protection and paint adhesion properties. Design and optimization of an efficient surface activation with the effective pretreatment of the surface for the deposition of reliable conversion coating shall be investigated. Corrosion resistance, coating adherence, multi-layer coating systems, simulated depot-level maintenance procedures including stripping/rework and their effects on the fatigue and corrosion resistance shall be investigated. The end result of the proposed research would be a complete environmentally green Trivalent Chromium based Conversion Coating process and product system as a performance and cost effective replacement for the carcinogenic Hexavalent Chromium Conversion Coatings on AMS 4434 Magnesium and Zinc-Nickel plated AISI 4130 and 4340 steel parts. BENEFIT: Magnesium alloys are used in military applications as helicopter gearbox casings, transmission casings, inline skates and some other high strength-low weight required applications. Kruger flaps, reverse thrust manifolds and control wheels found on many commercial aircrafts such as Boeing 727, 737 are sand-cast out of AZ92A alloy. The longest living aircraft B-52 Stratofortress brake calipers are manufactured out of AZ92A-T6. In spite of its high strength-to-weight ratio, magnesium alloys suffer from high corrosion rate coupled with complicated and expensive pretreatment routines. However, looking at the increasing trend of magnesium alloy usage in Military, Aerospace, Automotive sectors, METALAST believes a breakthrough in developing a successful replacement of hexvalent coatings would find widespread usage and demand. Cadmium plating of steel is another carcinogenic corrosion inhibition system restricted in many military applications. Zn-Ni plating, as a sacrificial layer, was found to be a suitable and economical alternative for various steel applications including fasteners, bolts and rivets. In the wake of recent EPA, OSHA and DoD directives for the replacement or limitation of the typical hexavalent conversion coating, there is a huge demand and need for an environmentally green yet potentially effective conversion coating system. Existing alternatives haven’t been either economical or potentially superior. METALAST International has often understood this need and demand from metal finishing industry. Hence, METALAST envisions the need and plans to utilize this opportunity through SBIR to develop an efficient replacement. Developing an environmentally green conversion coating will not only negate the health hazards but also increase the lifetime of both magnesium and Zn-Ni plated steel parts, the parts adjoined, subsequently reducing the high maintenance costs.
METALAST International, Inc. | Date: 2008-05-21
Chemicals for use in metal treatment, namely, corrosion inhibitors, painting bonding, conversion coatings, anodizing sealants.
METALAST International, Inc. | Date: 2012-04-17
Chemicals for use in metal treatment to prevent corrosion, consisting of cleaners, etchers, deoxidizers, dyes, electrolytic colors, sealants, electro polishers, anodizing additives, surfactants, acidifiers, basifiers, anodizing accelerators, fume suppressants, and anti foaming agents. Computer hardware systems comprising central processing units, computer monitors, computer input devices, namely, computer touch screens and keyboards, and computer interface controllers; computer software for controlling and monitoring metal treatment processes, storing data related to metal treatment, and for creating process verification reports.