Načela izbire materialov in prednosti aluminijevih zlitin za ladje

Načela izbire materialov in prednosti aluminijevih zlitin za ladje

Visoka specifična trdnost in specifični modul

Meja tečenja in elastični modul materialov sta najosnovnejša parametra za izračun trdnosti ladijskih konstrukcij in določanje strukturnih mer. Ker sta modul elastičnosti in gostota različnih aluminijevih zlitin približno enaka, in dodajanje majhne količine legirnih elementov ali spreminjanje stanja toplotne obdelave ima majhen učinek nanje, povečanje meje tečenja v določenem območju je koristno za zmanjšanje teže ladijskih konstrukcij. Na splošno, gostota aluminijevih zlitin je približno 2,7 ~ 2,8/cm3, and the elastic modulus is about 70~73GPa. Vendar, it is usually difficult for high-strength aluminum alloys to have excellent corrosion resistance and weldability at the same time. Zato, aluminum alloys for ships are generally selected from aluminum alloys with medium strength and corrosion resistance and weldability. Poleg tega, cast aluminum alloys also have certain applications in the field of ships.

Načela izbire materialov in prednosti aluminijevih zlitin za ladje

Odlična učinkovitost varjenja

For ships, welding connection has obvious advantages over riveting connection. Zato, welding connection method has been widely used in shipbuilding, basically replacing riveting structure. Trenutno, automatic argon arc welding method is mainly used in aluminum ship construction. The good weldability of aluminum alloy means that the tendency of cracks formed during welding of aluminum alloy is small, to je, aluminum alloy has good welding crack resistance, and the performance of welded joints does not change much after welding. Because the performance lost due to welding cannot be restored by re-heat treatment under shipbuilding conditions, this is one of the important characteristics of marine aluminum alloys that is different from other structural aluminum alloys. The strength of AL-Zn-Mg and AL-Mg-Si alloys is significantly reduced after welding, and the corrosion resistance of AL-Zn-Mg alloys is also poor after welding. Zato, these two alloys are subject to certain restrictions when used as welding ship materials. AL-Mg alloys do not have this disadvantage. Zlitine AL-Zn-Mg se uporabljajo predvsem za komponente, ki jih je po varjenju mogoče toplotno obdelati (kot so torpedne lupine), in zlitine AL-Mg-Si se uporabljajo predvsem kot profili.

Odlična odpornost proti koroziji

Strukture ladij se večinoma uporabljajo v surovih medijih z morsko vodo in morskih okoljih, ali so aluminijeve zlitine odporne proti koroziji, je torej eden od glavnih indikatorjev, ki določa, ali jih je mogoče uporabiti kot pomorske aluminijeve zlitine. Na splošno, zahteva se, da matrica iz aluminijeve zlitine in zvarjeni spoji niso nagnjeni k napetostni koroziji, korozija zaradi luščenja in interkristalna korozija v morski vodi in morskih okoljih; kontaktna korozija, čim bolj se je treba izogibati režni koroziji in morski biološki koroziji; in dovoljeni sta majhna enakomerna korozija in luknjičasta korozija.

Dobra zmogljivost hladnega in vročega oblikovanja

Med gradnjo, ships must undergo cold processing (such as folding, curling, upogibanje valjev, žigosanje, itd.) and hot processing (such as hot bending, pyrotechnic correction, itd.). Zato, marine aluminum alloys are required to be easy to process and form, without defects such as cracks during processing, and still meet the performance requirements of strength and corrosion resistance after processing.

Prednosti aluminijeve zlitine pri uporabi na ladjah

Aluminum alloy has the characteristics of low specific gravity and elastic modulus, odpornost proti koroziji, varivost, easy processing, non-magnetic and good low-temperature performance. It has the following advantages when used in ships:

• (1) Due to its low specific gravity, it can reduce the weight of the ship, reduce the capacity of the engine, and increase the speed; it can reduce fuel consumption and save fuel; it can improve the length-to-width ratio of the ship, increase stability, and make the ship easier to operate; lahko tudi poveča nosilnost in pridobi dodatne dobičke.
• (2) Zaradi dobre odpornosti proti koroziji, lahko zmanjša stroške vzdrževanja, kot je oljenje, in podaljša življenjsko dobo (običajno več kot 20 leta).
• (3) Ima dobro zmogljivost obdelave in oblikovanja ter je enostaven za izvajanje različnih oblik obdelave, kot je rezanje, žigosanje, hladno upogibanje, oblikovanje in rezanje, ki je primeren za racionalizacijo trupa; lahko ekstrudira velike široke in tankostenske profile, zmanjšajte število zvarov in naredite strukturo trupa bolj racionalno in lahko.
• (4) Ima dobro varilno zmogljivost in ga je lažje variti.
• (5) Ima majhen modul elastičnosti, velika sposobnost absorbiranja udarne napetosti, in večjo varnost.
• (6) Aluminijaste odpadke je enostavno reciklirati in jih je mogoče ponovno uporabiti.
• (7) It is not brittle at low temperatures and is most suitable for low-temperature equipment.
• (8) Since it is non-magnetic, the compass is not affected; all-aluminum ships can avoid mine attacks and are suitable for minesweepers.
• (9) It is free of insect pests and dry deformation; it does not burn and is safer in case of fire.

More knowledge about marine aluminum plates: https://hw-alu.com/applications/aluminum-sheet-for-boat.html