Objective

The Chemical Agent Resistant Coating (CARC) System application specification, MIL-C-53072, requires that metal surfaces on tactical vehicles be treated to improve adhesion and corrosion resistance prior to coating with an epoxy primer and a camouflage topcoat. In original equipment manufacturer (OEM) processes, the surface treatment is generally performed by a five-stage dip process such as zinc phosphate as prescribed in TT-C-490. In depot operations and for touch-ups in OEM processes, the surface treatment requirement is met through the pretreatment wash primer, DOD-P-15328. Since this formulation contains 7.1% zinc chromate and has 6.5 lb/gal of volatile organic compounds (VOC) that are classified as hazardous air pollutants (HAP), there is a need to develop an innovative and cost-effective replacement technology to address the multiple health, safety, and compliance issues associated with the current systems while maintaining military readiness for national defense.

The overall objective of this project is to provide the Department of Defense (DoD) with a novel pretreatment technology that is both environmentally acceptable (no HAPs or regulated heavy metals such as Cr⁶⁺ or Ni) and cost effective. The specific technical objective is to develop and optimize a zirconium-based surface treatment with the following attributes: (1) ease of application using existing spray, immersion, or repair methods with minimal infrastructure modifications; (2) performance equal to (or better than) existing Cr⁶⁺ wash primers; (3) broad compatibility with the current suite of military coatings (including solvent and water-based primers and topcoats); and (4) compatibility with a broad range of metallic and nonmetallic substrates.