Let’s get to know the ships, which are the captains of an immense watery realm, more closely with material science …
Heat-resistant, fireproof materials are preferred in the living spaces inside the ship. For example, rock wool or glass wool. Plastic and copper materials are preferred for insulation in wiring. Concrete is among the choices for floors. According to what has been written so far, the areas where the ships, which are not different from the house, differ with their material structure are the parts that make up the strength structure of the ship. The most important feature sought in these materials is the ease of workability at the production stage. When we dive into the Bosphorus, the commercial ships we see are generally made of steel. When lightness is desired, aluminum and fiber reinforced plastics are used. When we compare the history books, we can see that the ships produced for the first time used wood as the main material.
Generally, the required properties from the materials used in shipbuilding: It should be able to meet the compression, tensile and shear stresses on the material; Hardness, brittleness, fatigue strength and fire resistance should be at the desired values. In general, we learned about the ships and the materials used in the ship. Now let’s examine the materials that make up the strength of the ship.
Steel Materials (How is steel produced)
Steels are obtained by blowing oxygen to crude iron obtained from ore or by remelting the scraps in electric arc furnaces. It consists largely of iron and controlled carbon. Substances such as sulfur, silicon, and phosphorus are kept to a minimum. If the chemical structure is desired to be changed, alloying materials such as chrome, nickel, manganese are added. The steels used in ships are generally on mild steel in terms of price and availability. Another nice aspect of soft steel is that it is suitable for processes such as hot-cold forming and welding. On the negative side, when the temperature is lowered too much, the impact hardness decreases and fragility begins. The Class Society inspects the availability of any steel on board. As we classify people as a society, these institutions classify steels from A to E. Mild steel is in A and B classes. High tension steels are used in warships such as tankers where stresses are high and weight is important. In ships carrying LPG and LNG fuels, steel materials that do not become brittle and do not show corrosive effects are preferred due to environmental conditions.
Although aluminum has the same yield stress as steel, its density is about one-third, aluminum is much lighter than steel because its buckling strength is lower than steel. If we ask what is the biggest disadvantage of aluminum? Of course, it is possible to answer as the price in the production stage and the difficulty of welding. To make the price concrete, the unit price of steel used in shipbuilding is $ 2.0 / kg, while aluminum is $ 12.0 / kg. This leads to one more consideration when using aluminum during shipbuilding. Aluminum is used in some cases only in the superstructure of the ship, in a small area. They say fire and gunpowder do not stop somewhere. The same can be said for aluminum and steel. Electro-chemical corrosion occurs in places where aluminum and steel come into contact. In fact, we can say that over time, steel aluminum consumes space. Corrosion can be prevented with the help of neoprene or a similar material. It is determined, inspected and documented by classification societies in aluminum like steel.
Fiber Reinforced Plastic
(FRP) It is produced by mixing fiber reinforced plastic braids and short free fiber layers with the help of synthetic resin. The most used resins are polyester, vinly ester, epoxy and phenolic resins. While most glass fiber is used in the fiber category, carbon or aramid fiber can also be used rarely. Apart from sandwich construction, male or female molds are used in the production of FRP structures. Fiber reinforced plastic is used in shipboard high-speed machines, coolers, office cabinets and room isolation.As in steel and aluminum, the material properties and production in FRP are determined, inspected and documented by class institutions.
While space exploration hasn’t really begun, we can at least have a little practice exploring the oceans and seas on earth. The confidence of the ships that will captain us in this discovery depends entirely on material science. When we look at the past, we can see that the ships were predominantly wooden materials, and nowadays wood has generally been replaced by steel and aluminum alloys. In the coming years, we will fill our pockets with more efficient and quality materials because science always wants to change and develop.