Overlay/Bond Coatings that Resist Hot Corrosion in Navy Gas Turbines - SBIR Topic DON26BZ01-NV028

Disclaimer:
This topic was temporarily posted by the Department of War SBIR Program on March 2nd 2026 and removed the following day.
We believe this topic is planned to be released once the SBIR program is reauthorized; however, this topic may ultimately be modified or withdrawn.

Sign up below to be notified as soon as this topic is released again. In the meantime, we’d recommend you start planning to respond if within your capabilities.

Funding Amount:

Est. $240,000

Deadline to Apply:

Est. April 29th, 2026.

Objective:

Develop overlay or bond coatings and a coating model that enables longer service and prediction of corrosion, oxidation and overall degradation when exposed to marine Naval environments as a function of corrosivity, stress, and various temperature combinations via integrated computational material engineering (ICME), which will foster creation of new coatings resistant to these degradation modes.

Description:

Marine gas turbine engines serve as primary and auxiliary power sources for several current classes of ships in the U.S. Navy. It is desirable for marine gas turbine engines to have a mean time between removals of 20,000 hours. While some engines have approached this goal, others have fallen significantly short. The main reason for this shortfall is various forms of hot corrosion (Type I and Type II) damage in the hot section turbine hardware due to intrusion of salts from the marine air and/or from sulfur in the gas turbine combustion fuels.

The synergistic effect of stress- and deposit-induced high temperature corrosion can lead to other corrosion mechanisms. Corrosion fatigue as well as fatigue often initiates at stress risers. Metallurgical examination of several failed marine gas turbine blades that had operated between 5,000 and 10,000 hours was performed and compared to “unfailed” blades with 18,000 operating hours from a similar marine engine. Deposition occurring at sites under the platform of unfailed turbine blades revealed pitting at those sites.

Further examination revealed poor coating quality (i.e., high porosity and variable thickness) under the platform of first stage turbine blades that allowed salts to permeate through the coating to the alloy surface and initiate hot corrosion. Further coating examination under the platform showed highly variable coating thicknesses (0-40 µm) in the curved area of transition between the under platform and the blade stem. In a few cases, coatings were non-existent on the “unfailed” blades. The Cobalt Chromium Aluminum Yttrium (CoCrAlY) coating, when present, usually was porous or the available coating under the platform was highly contaminated due to lack of adequate spray deposition in these non-line-of-sight areas. CoCrAlY coating thicknesses at other sites along the blade stem were 35 µm to 105 µm (1.4 to 4.1 mils) and devoid of porosity. The corrosion that was observed under the platform in all cases was caused by Type II, low-temperature hot corrosion, which occurs in the temperature range of 649°-732°C (1,200°-1,350°F). Corrosion penetrated the porous coating and caused further undercutting of the coating along the coating/alloy substrate interface, Type II hot corrosion caused pitting at these locations under the platform, which caused stress risers where corrosion fatigue cracks initiated. These pits advanced through the blade stems to varying degrees.

The synergistic effect of stress- and deposit-induced high temperature corrosion leads to the premature failure of aero turbine blades reportedly due to stress corrosion cracking. The lower shank of aero gas turbine blades, which operates below 600°C is susceptible to this mode of failure. Two important factors that lead to stress corrosion cracking of single crystal nickel-based superalloys are the type of deposits that form on components (these include alkali chlorides and sulfates which are introduced through the environment) and the concentration of SOx in the environment. Therefore, it is important to understand the synergistic role of deposits and sulfur containing gases on the stress corrosion cracking susceptibility of single crystal nickel-based superalloys below 600°C.

Who will win?

If you can achieve the objective above better than any other company on the market, you have a very high-likelihood of success and should apply.

Who is eligible to apply?

Any company that meets the following criteria:

• For-profit company

• U.S.-owned and controlled.

• 500 or fewer employees (including affiliates)

How Can BW&CO Help?

1) End-to-end support including, strategy, writing of the full proposal, and administrative & compliance support.

2) Proposal strategy and review.

3) Administrative & compliance support.

Request to talk with a member of our team by completing the form below: