In designs marine vessels, as well as facilities on the beach and on the high seas, the following types of products from wrought aluminum alloys:
- pipe and
Aluminum sheets and plates are produced by cold or hot rolling. Aluminum profiles, rods and tubes can be produced by compression methods, rolling or drawing. Details on the application of aluminum in shipbuilding cm. article marine aluminum.
All “sea” aluminum alloys
Aluminum alloys, which are used in marine shipbuilding and marine infrastructure constructions, are presented in the table below.
“sea” alloys – aluminum-magnesium alloys (5xxx)
The use of aluminum alloys 5xxx series, It is mainly in the form of sheets and plates, but it can be and profiles, and rods, and rods. All of them are used in the annealed condition O and its related conditions N111 and N112, able N116, as well as a variety of cold-worked condition – H32, N34, N321. Normalized tensile strength of the alloy 5083 able to H32 or H321 is from 305 to 380 MPa, yield strength - at least 220 MPa.
Category H3 cold-worked state includes stabilizing annealing to stabilize the mechanical properties, increasing plasticity and formability characteristics, for example, of the minimum bending radius.
Standing N116 and H321 introduced into the international classification specifically to the 5xxx series alloys with magnesium content more 3 %. 5xxx series alloys in the N116 and H321 are used almost exclusively for sheets and plates.
Status N116 applies to products, which are made of the 5xxx series alloys with magnesium content more 3 %. They nagartovyvayutsya during the last processing step to the preset stable strength characteristics and must have a predetermined level of corrosion resistance in accelerated corrosion tests. They are designed for continuous operation at temperatures above 65 oC. Tests carried out on the intergranular corrosion and subsurface.
H321 condition also applies to products, which are made of the 5xxx series alloys with magnesium content more 3 %. They are subjected to the stabilizing annealing after the final processing step to achieve the desired strength characteristics stable and must have a predetermined level of corrosion resistance in accelerated corrosion tests.
“sea” 6xxx series alloys
The profiles of aluminum alloys 6xxx series, thermally hardened, apply in states T4, T5 and T6. Normalized Strength Aluminum Alloys 6005A i 6082 able to T5 or T6 is not less than 260 and 290 MPa, yield strength - at least 215 and 240 MPa, respectively
In Europe, the base alloy for the manufacture of sheets and plates is an aluminum alloy 5083, for profiles - alloys 6005 and 6082 (cm. Aluminum boats on shipbuilding alloys in the USA). The remaining aluminum alloys are used for auxiliary structures and with careful justification. As for the alloy welding wire used mainly aluminum alloy 5183. For the underwater parts used, usually, Only aluminum alloy 5083. The use of aluminum alloys 6xxx series in structural elements, exposed to direct contact with sea water, allowed only, if taken adequate measures for their corrosion protection.
OFFSHORE STANDARD DNV-OS-B101, METALLIC MATERIALS, 2009