TOPIC 2 Introduction to environmental internal and external

TOPIC 2 : Introduction to environmental internal and external ship materials

Materials Science and Engineering • The combination of physics, chemistry, and the focus on the relationship between the properties of a material and its microstructure is the domain of Materials Science. • The development of this science allowed designing materials and provided a knowledge base for the engineering applications (Materials Engineering). • To be able to select a material for a given use based on considerations of cost and performance. • To understand the limits of materials and the change of their properties with use. • To be able to create a new material that will have some desirable properties.

• Structure • At the atomic level: arrangement of atoms in different ways. (Gives different properties for graphite than diamond both forms of carbon. ) • At the microscopic level: arrangement of small grains of material that can be identified by microscopy. (Gives different optical properties to transparent vs. frosted glass. ) • Properties • way the material responds to the environment. For instance, the mechanical, electrical and magnetic properties are the responses to mechanical, electrical and magnetic forces, respectively. • Other important properties are thermal (transmission of heat, heat capacity), optical (absorption, transmission and scattering of light), and the chemical stability in contact with the environment (like corrosion resistance). • Processing • application of heat (heat treatment), mechanical forces, etc. to affect their microstructure and, therefore, their properties.

Classification of Materials • Hull Materials • • • COLD-PROOF WELDING HULL STEELS HIGH-STRENGTH CLAD CORROSION-RESISTANT STEEL HIGH-STRENGTH NON-MAGNETIC STEELS ALUMINUM 1575 (Al-Mg system) ALUMINUM 1561 (Al-Mg system) PANELS OF ALUMINUM ALLOYS STEEL-ALUMINUM BIMETAL WITH ASYMMETRICAL LAYER ARRANGEMENT WELDING OF TITANIUM-STEEL BIMETALS WELDING OF HIGH-STRENGTH TITANIUM ALLOYS WELDED STRUCTURES OF TITANIUM ALLOYS STYRENE-FREE POLYETHER STRUCTURAL GLASS PLASTIC THREE-LAYER POLYETHER STRUCTURAL GLASS PLASTIC FOR SHIP HULLS

• COLD-PROOF WELDING HULL STEELS • Meant for fabrication of welded structures used at temperatures up to -60°C under attack of sea water. Fields of application hulls of icebreakers, lighteraboard ships ice-resistance oil-rig platforms building structures pressure vessels Advantages high processability; hydrogen-sulfide cracking resistance; resistance to layered failures; high cold resistance to (-) 60°.

• HIGH-STRENGTH CLAD CORROSION-RESISTANCE STEEL • hulls of ice ships and icebreakers; • water-development works. • HIGH-STRENGTH NONMAGNETIC STEELS • These steels are used for making heavily loaded parts, units, structures in the power plant industry, instrument making and shipbuilding, drilling rigs. • Advantages • combination of lack of magnetic properties and high strength; • compatibility with pearlitic steels during operation in corrosive media; • reliability and extended life time; • high level of mechanical properties in the wide negative temperature range;

• ALUMINUM 1561 (Al-Mg system) • This is an effective material for new high-speed air-cushion and hydrofoil vessels. • Alloy: • • corrosion-resistant weldable easy to deform This higher strength alloy, which has been in service on board sea -going vessels for more than 30 years, works in the tempearture range from (-)196°C to (+) 70°C under severe corrosive conditions.

• ALUMINUM 1575 (Al-Mg system) • High-strength aluminum for marine application with a unique homogeneous fine-grained structure used in the heavily loaded lightened constructions of high-speed vessels and ground-effect craft. • Alloy: • nonheat-strengthened; • weldable; • it has an excellent corrosion resistance to attack by sea water

• THREE-LAYER POLYETHER GLASS PLASTIC FOR SHIP HULLS • The plastic is intended for production of serviceable, easily producible hulls of trawlers, mine-sweepers, high-sped vessels where dynamic principles of maintenance are used, sea yachts. • The polyether glass plastic is environmentally safe, ensures habitability conditions; it is almost inflammable, with a low speed of the flame propagation over the surface • Technologically effective structure of a hull with a small number of framework beams which provides for simplification of building methods at maintaining a high level of strength and serviceability. • High level of strength and rigidity in combination with low density.

Shipbuilding Materials • Shipbuilding steel • is the most common material. • It is to meet rather strict requirements: strength, flexibility, high manufacturability, weldability, cost, reparability, etc. • Steels used in the domestic shipbuilding industry, good welding characteristics and increased fracture strength. • Structural aluminum alloys • increased corrosion resistance as well as aluminum-based composite materials became common use in construction of high-speed sea and river vessels, as well as airfoil boats, hydrofoil ships and aerostatic crafts. • Titanium alloys • became common use in marine facilities. • Distinctive characteristic of their usage is wide spectrum of operational environment with long service life.

• Zinc • rather corrosion-resistant material both in air and in water. • Rolled zinc is used in inboard planking of ship rooms. • Zinc coating becomes common use in corrosion prevention for metal surfaces of ship systems. • Fiberglass plastics • are used in construction of hulls of some vessels (trawlers, sweepers, high-speed airfoil and hydrofoil ships, and yachts). • The main property of the fiberglass plastics is their chemical and biological stability. • Strength and technological properties, improvement of working conditions, and reduction of costs of workroom air ventilation are their advantages.

CONSTRUCTION, MAINTENANCE AND REPAIR • The most direct environmental impact from shipbuilding is naturally incurred by the shipyards‘ own activities, which apart from the construction of ships typically also include ship maintenance and repair services. • Each of these processes is a major undertaking in its own right and includes a large number of intermediate steps: • handling of raw materials; fabrication and surface treatment of basic steel parts; • joining and assembly of fabricated parts into blocks; • erection of ship structures through the fitting and welding of blocks; • outfitting of ships with electronic equipment; and • preparation and installation of various fabricated parts that are not of a structural nature.

• Maintenance and repair activities typically include: • Surface cleaning and treatment operations; • oil transfer operations; and • servicing of machinery and other equipment. • Construction, maintenance, and repair activities involve the generation and daily handling of a large number of toxic materials, fumes and fluids. Metal work and surface treatment operations, for example: • generate particulate matter (PM) emissions and may lead to the discharge of toxic compounds to soil and water. • Routine maintenance activities generate waste engine fluids, such as oil, hydraulic fluids, lubricants, and anti-freeze. Fuelling activities generate waste liquids and vapour releases to the air. • The extensive use of underground storage tanks likewise carries the risk of the release of pollutants that can harm aquatic life. • Bilge and ballast waters are additional waste streams are that contain oil, solvents and other hazardous substances.

• The activities in shipbuilding that are of highest direct environmental concern include: • metal working activities, including thermal metal cutting, welding and grinding; • surface treatment operations, including abrasive blasting, coating and painting; • ship maintenance and repair activities, such as bilge and tank cleaning; and • noise.