Iranian Classification Society Rules

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Section 8 Aluminium Alloys

801. Aluminium alloys

1. Mechanical properties

(1) In connection with the 801. 1 (2) of the Rule, aluminium alloys exceeding the maximum value

of plate thickness or size specified in Table 2.1.98 and Table 2.1.99. are

quirements given in Tables 2.1.14 of the Guidance.

comply with the re-

Table 2.1.14 Mechanical Properties for Alluminium Alloys(1)

Product

Grades

Temper condition(2)

Thickness,

(mm)

Tensile test

Yield strength ( )

Tensile strength

( )

Elongation(%)

(

)

Rolled

5083P

50< 80

115 200

270 345

14 min.

80< 100

110 min.

260 min.

12 min.

H321

50< 80

200 295

285 385

11 min.

Extruded Shapes

5083S

50< 130

110 min.

275 355

10 min.(3)

NOTES :

(1) Aluminium alloy may be subject to any other standards in lieu of the requirements given in this Table where they are approved by the Society.

(2) Symbols used in temper condition are as follows : O : Annealing

H321 : Stabilizing treatment after work hardened

And definitions of the symbols used in temper condition are to comply with the requirements in Table 2.1.15 of the Guidance.

(3) The values are applicable for longitudinal and transverse tensile test specimens as well.

(2) In connection with the 801. 5 (2) of the Rule, for verification of proper fusion of press welds for closed profiles, the Manufacturer has to demonstrate by drift expansion tests of closed as follows;

(a) Batches of five profiles or less shall be sampled one profile. Each profile sampled will have two samples cut from the front and back end of the production profile. The test specimens

are to be cut with the ends perpendicular to the axis of the profile.

(b) Profiles with lengths exceeding 6 m shall be sampled every profile in the start of the production. The number of tests may be reduced to every fifth profile if the results from the first 3-5 profiles are found acceptable.

(c)

(d)

The size of the specimen and testing procedure are to be in accordance with the require- ments in 401. 5 (3) of the Rule.

The sample is considered to be unacceptable if the sample fails with a clean split along the

weld line which confirms lack of fusion.

2. Heat treatment

In application to 801. 4, Note (2) of Table 2.1.99 and Table 2.1.100 of the Rules, definitions of the symbols used in temper condition are to comply with the requirements in Table 2.1.15 of the Guidance.

22 Guidance Relating to the Rules for the Classification of Steel Ships 2015

Table 2.1.15 Definition of the symbols used in temper condition

Symbols

Definition (1)

Application(1)

Annealing

Applies to wrought alloys which are annealed to obtain the softest temper

H111, H112 and

H 116

Work hardened only.

Applies to products which are strain-hardened to achieve the strength desired without additional thermal treatment

H 321

Stabilizing treatment after work hardened(2)

Applies to alloys that are strain-hardened and whose mechanical properties are stabilized by a low temperature thermal treatment that results in slightly lowered tensile strength and improved ductility.

Artificial age hardening only(3)

Applies to alloys which are not cold worked after cooling from an elevated temperature shaping process

Artificial age hardening treatment(3) after solution treatment(4)

Applies to alloys which are not cold worked after solution heat-treatment

Note

(1) Refer to K S D0049(Ferrous products Heat treatments Vocabulary) and K S D0004(Temper Designation for Aluminium and Aluminium Alloys)

(2) Stabilising is the relief of residual internal stresses by heating to a predetermined temperature, usually in the region of 250ºC, then cooling slowly.

(3) Age hardening is the increasing the hardness of an alloy by a relatively low-temperature heat treatment that causes precipitation of components or phases of the alloy from the supersaturated solid solution.

(4) Solution treatment is the heating and holding an alloy at a temperature at which one (or more) constituent enters into solid solution, then cooling the alloy rapidly to prevent the constituent from precipitating

3. Corrosion testing

In application to 801. 9 (2) (a), (c) of the Rules, the term "equivalent standards agreed by the Society" means the acceptance in accordance with Pt 1, Ch 1, 104. or 105. of the Guidance.

4. Surface inspection and dimensional tolerance

(1) In application to 801. 10 (2) of the Rules, the term "deemed appropriate by the Society" means the acceptance in accordance with Pt 1, Ch 1, 104. or 105. of the Guidance.

(2) "Dimension tolerance except those specified in previous (2)" given in requirements of 801. 10

(3) of the Rules may comply with a recognized national or international standard accepted by

the Society.

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