SBIR-STTR Award

Cathodic protection methods, employing a sacrificial anode, are used to prevent corrosion of iron-based structural components in marine environments. However, as a consequence of galvanic coupling, hydrogen charging of high-strength steels occurs leading to hydrogen embrittlement and stress-corrosion cracking (SCC). Under this proposed SBIR program, QuesTek Innovations LLC, a leader in the field of computational materials design, will develop a new alloy with a corrosion potential tuned to about -0.8V, with maximum current carrying capacity, that can eliminate or reduce the risk of hydrogen embrittlement of high strength materials, while providing efficient cathodic protection against corrosion. Based on QuesTeks electrochemical framework alloying additions will be incorporated to achieve the desired corrosion potential along with a non-passive soluble oxide film. QuesTeks mechanistic and computational Materials by Design methodology is a viable strategy to rapidly develop an effective material solution with the ideal electrochemical and active corrosion properties. In the program QuesTek will partner with OEMs who will help define the material and process requirement matrix, and ultimately lead the alloy implementation. Concept feasibility will be demonstrated by cyclic polarization tests on model alloys fabricated in the Phase I program. Production-scale fabrication of the designed alloy will be demonstrated in Phase II.

Benefit:
Advanced naval structures, as found on the Virginia Class Submarines, employ advanced, high-strength structural materials for fasteners and other components that enable higher performance submarines. These components become susceptible to SCC if the difference in corrosion potential between the component and the sacrificial anode is too high for a given material and strength level. The outcome of this proposed SBIR program is the design and development of a new alloy with a corrosion potential tuned to about -0.8V, with maximum current carrying capacity, that can eliminate or reduce the risk of hydrogen embrittlement of high strength materials, while still providing efficient cathodic protection against corrosion. Secondary benefits will include reduced replacement frequency and/or reduced weight of the sacrificial anode. Other project goals will include maintaining low alloy cost, achieved through a reduction in processing cost, and by licensing the alloy to multiple suppliers. The growing use of off-shore technologies and facilities (e.g. wind energy, wave energy, hydrocarbon extraction) appear to constitute a growing market need for targeted sacrificial anodes beyond marine vessels.

Keywords:
SCC, SCC, sacrificial anodes, Materials by Design, Zinc, Aluminum

Cathodic protection methods, employing a sacrificial anode, are used to prevent corrosion of iron-based structural components in marine environments. However, as a consequence of galvanic coupling, hydrogen charging of high-strength steels occurs leading to hydrogen embrittlement and stress-corrosion cracking (SCC). Under this proposed SBIR program, QuesTek Innovations LLC, a leader in the field of computational materials design, plans to develop, and qualify a domestically supplied alloy with a corrosion potential tuned to about -0.8V (vs. Ag/AgCl), with maximum current carrying capacity, that can eliminate or reduce the risk of hydrogen embrittlement of high strength materials while providing efficient cathodic protection against corrosion. During the Phase I program QuesTek applied its Materials by Design methodology to design a series of alloy compositions that met or exceeded the program goal for anode efficiency at three different voltage levels within range targeted in the solicitation. Phase II efforts will focus on the optimization, scale-up, and qualification of a final anode composition and process path. At the end of Phase II QuesTek anticipates generating all qualification data needed to include the alloy in the MIL-DTL-24779 specification. In Phase III our efforts will be expanded to develop applications with similar requirements in the commercial sector.

Benefit:
Advanced naval structures, as found on the Virginia Class Submarines, employ advanced, high-strength structural materials for fasteners and other components that enable higher performance submarines. These components become susceptible to SCC if the difference in corrosion potential between the component and the sacrificial anode is too high for a given material and strength level. The outcome of this proposed SBIR program is the design and development of a new alloy with a corrosion potential tuned to about -0.8V, with maximum current carrying capacity, that can eliminate or reduce the risk of hydrogen embrittlement of high strength materials, while still providing efficient cathodic protection against corrosion. Secondary benefits will include reduced replacement frequency and/or reduced weight of the sacrificial anode. Other project goals will include maintaining low alloy cost, achieved through a reduction in processing cost, and by licensing the alloy to multiple suppliers. The growing use of off-shore technologies and facilities (e.g. wind energy, wave energy, hydrocarbon extraction) appear to constitute a growing market need for targeted sacrificial anodes beyond marine vessels.

Keywords:
low-voltage, Materials by Design, SCC, Aluminum, sacrificial anodes