The Advantages of Basalt Glass Flake Coating for Marine Anticorrosion

Harsh marine environment makes anticorrosion to be a technical challenge of ocean engineering. Glass flake, as the pigment for under seawater coating, is required by anticorrosion standard and has been the bottleneck of Chinese marine technology. Basalt planar glass flake is novel anticorrosive pigment developed by the authors, which is environmentally friendly, strong, heavy-duty anticorrosion, water impermeable, anti-weather and UV blocking and superior to the traditional c-glass flake and basalt glass-ceramic flake. Epoxy resin has excellent properties of film forming, corrosion resistance, low permeability, high adhesion and dimensional stable. Hence, basalt glass flake reinforced epoxy resin coating has significant advantages in the marine engineering, in terms of anticorrosion.

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Process Stability, Microstructure and Mechanical Properties of Underwater Submerged-Arc Welded Steel

Metals ◽

10.3390/met11081249 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1249

Author(s):

Maofu Zhang ◽

Yanfei Han ◽

Chuanbao Jia ◽

Shengfa Dong ◽

Sergii Maksimov ◽

...

Keyword(s):

Mechanical Properties ◽

Epoxy Resin ◽

Water Glass ◽

Welding Process ◽

Process Stability ◽

Surrounding Water ◽

Welded Steel ◽

Underwater Wet Welding ◽

Marine Engineering ◽

High Level

In underwater wet welding, the unstable welding process caused by the generation and rupture of bubbles and the chilling effect of water on the welding area result in low quality of welded joints, which makes it difficult to meet the practical application of marine engineering. To improve the process stability and joining quality, a mixture of welding flux with a water glass or epoxy resin was placed on the welding zone before underwater welding. In this paper, welds’ appearance, geometry statistics of welds’ formation, welding process stability, slag structure, microstructure, pores and mechanical properties were investigated. It was found that with the addition of water glass in the mixture, the penetration of weld was effectively increased, and the frequency of arc extinction was reduced. Though the porosity rose to a relatively high level, the joints’ comprehensive mechanical properties were not significantly improved. Notably, the applied epoxy resin completely isolated the surrounding water from the welding area, which greatly improved process stability. Furthermore, it benefited from the microstructure filled with massive acicular ferrite, the average elongation and room temperature impact toughness increased by 178.4%, and 69.1% compared with underwater wet welding, respectively, and the bending angle of the joint reaches to 180°.

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Improving the Conceptual Design Process for Unmanned Underwater Vehicles

10.5957/attc-2017-0014 ◽

2017 ◽

Author(s):

Alexander Laun

Keyword(s):

Conceptual Design ◽

Design Process ◽

Systems Engineering ◽

Traditional Approach ◽

Cost Effective ◽

The United States ◽

Engineering Systems ◽

Ocean Engineering ◽

Unmanned Underwater Vehicles ◽

Marine Engineering

With a renewed global focus on anti-submarine warfare (ASW), the United States Navy will increasingly rely on unmanned underwater vehicle (UUV) technology to serve as a cost-effective force multiplier. Modern UUV development necessitates a uniquely constrained, iterative approach to the traditional submarine design spiral. Considering a broad spectrum of customer-generated requirements, the UUV conceptual design process applies the best practices of naval architecture, marine engineering, ocean engineering, systems engineering, and submersible design. This paper provides an assessment of the traditional approach to the UUV design and development process. Specifically, this paper analyzes the design philosophy for modern UUVs, provides a design framework for the UUV conceptual design process, and details specific recommendations to encourage innovation in the subsea realm.

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