Patented technology avoids significant costs by applying reverse sensitization in
aluminum structures
Concurrent Technologies Corporation’s (CTC’s) patented Reverse Sensitization Unit
(RSU) technology mitigates sensitized 5xxx aluminum structures, effectively “reverse
sensitizing” them. Using the RSU, sensitized aluminum structures can be returned
to their previously unsensitized state while in place, without the need to remove
or replace the sensitized material.
Why CTC’s Solution is So Valuable
5xxx series aluminum alloys are strong, light, weldable, relatively inexpensive,
and when new, generally corrosion resistant. These alloys have been used in many
applications, particularly ship structures. After prolonged exposure to elevated
in-service temperatures, 5xxx series aluminum becomes sensitized. When this occurs,
the exposed structures become highly susceptible to pitting corrosion and stress
corrosion cracking. Repairs of cracks in sensitized 5xxx aluminum structures require
expensive, specialized treatments and complex welding procedures. In many cases,
the sensitized material is beyond repair, and complete material replacement with
large panel inserts is necessary.
How it Works
CTC’s RSU consists of five components. Reverse sensitization is accomplished by
applying the heating component of CTC’s RSU (seen to the right) directly to the
sensitized structure.
CTC’s full RSU, applied to sensitized ship deck, is shown to the right. After application
of heat, in accordance with specific time / temperature parameters, the material
is allowed to cool and the RSU is removed and placed on the next area to be reverse
sensitized.
Why is This Better?
CTC’s RSU reverses sensitization in the affected plate(s) to provide a remediated
existing structure, preventing cracking and pitting damage through reduction of
sensitization. In doing so, CTC’s RSU provides significant labor and materials cost
avoidance when compared to removal and replacement of the sensitized material. The
RSU can also reduce time to repair, as the process takes hours to reverse sensitize
an area as opposed to days for repair and replacement.
Benefits of CTC’s Reverse Sensitization Unit
- Man portable – CTC’s RSU is designed to be easily transported throughout all areas
of a ship
- Easily stored in hardened cases (provided)
- Provides significant cost avoidance over removal and replacement of sensitized aluminum
structures
- Enhances mission readiness by reducing time to repair with reverse sensitization
as compared to removal and replacement
- Preserves material strength–no material weakening due to reverse sensitization
- Can be applied vertically or horizontally by use of the attachment component (as
seen to the right)
- Heat from the RSU is contained and prevented from affecting surrounding areas by
use of the boundary component (as seen to the right)
- Easy to operate
- Full training program on RSU operation and maintenance is available
- CTC’s current RSU configuration is specifically designed to treat superstructure
components made from 0.25-inch-thick 5456/H116 aluminum alloy plate on U.S. Navy
CG-47 Class. However, the technology is licensed to applicators that can not only
provide RSU application on-site but can also provide a configurable RSU solution
for different applications. Additional RSUs can be designed and configured as needed.
