The People's Republic of China Electric Industry Standard (SJ/T 11223-2000)
                  Copper Clad Aluminum Wire
Foreword

This standard dosen't adopt ASTM B 566 : 1993 «Copper Clad Aluminum Wire Standard Specification»equivalently and the difference between them is as follows:
1) In Area part, it is added that this standard is suitable for the copper clad aluminum wire used in coaxial cables and wires & calbes in electric equipments;
2) In Sources of Standard part, the test method adopts the national relevant standards;
3) In Classification & Model part, CCA is used as the model code of copper clad aluminum wire;
4) In table Tensile Strength & Extensibility, the nominal diameter is adjusted properly and the value of tensile strength is made some necessary modification;
5) It is added with the nominal density value and its deviation of copper clad aluminum wire, and the test method is also regulated. It will be taken as one of the examination items if it is ordered in the contract;
6) It is added with App. A Copper Clad Aluminum Wire HF Skin Depth Property.
The App.A of this standard is the prompted appendix.
This standard is presented by the Ministry of Information Industry of the People's Republic of China.
The standard is reserved by the Electric Industry Standardization Institute of the Ministry of Information Industry.

1 Area

This standard regulates the copper clad aluminum wire's product classification, requirement, test method, packing, mark, transport and storage etc.
This standard is applied to the copper clad aluminum wire that is used as the internal conductor of coaxial cable and the wire & cable conductor in electric equipments.

2 Sources of Standard

Those contained in the following standards become items of this standard by being quoted in the standard. When it is published, all editions are valid and will be modified. Those who want to use this standard should discuss the possibility to use the latest edition of the standars below.
GB/T3048.2 - 1994 Wire & Cable Electrical Property Test Method & Metallic Material Resistivity Test
GB/T 4909.2-1985 Bare Wire Test Method & Size Measurement
GB/T 4909.3 - 1985 Bare Wire Test Method & Tension Test
GB/T 4909.4 - 1985 Bare Wire Test Method & Torsion Test
GB/T 4909.5 - 1985 Bare Wire Test Method & Bending Test & Reverse Bending

3 Terms (3.1-3.5 short)

3.1 unit of product
3.2 inspection lot
3.3 sampling unit
3.4 sample
3.5 specimen

4 Classification & Type
4.1 Classification

According to different copper layer volume ratio and soft or hard state, the copper clad aluminum wire is classified into 4 types:
10A the copper layer volume ratio is 10%, soft;
10H the copper layer volume ratio is 10%, hard;
15A the copper layer volume ratio is 15%, soft;
15H the copper layer volume ratio is 15%, hard.

4.2 Model

The model of copper clad aluminum wire is composed of model code (CCA), type code (10A, 10H, 15A, 15H) and its nominal diameter.
It is expressed as:

5 Requirements
5.1 Appearance

The copper clad aluminum wire is composed of aluminum core wire and the copper layer cladding tightly on it. The copper layer should clad evenly and constantly on the aluminum core wire, with its surface smooth without any defect such as the dent, crack, exposed aluminum and obvious rusty spot etc.

5.2 Nominal Diameter & Deviation

The nominal diameter of copper clad aluminum wire should meet the regulation in Table 1 without extra regulations. As to the deviation, it should be within ± 0.003mm if the diameter is less than 0.300mm, otherwise it should be less than ± 1% of the nominal diameter (the value is calculated exactly to two figures behind the radix point).

5.3 Copper Layer Thickness

The thinnest spot of the copper layer should meet the following regulations:
5.3.1 As to 10A and 10H, the thickness shouldn't be less than 3.5% of the wire radius.
5.3.2 As to 15A and 15H, the thickness shouldn't be less than 5.0% of the wire radius.

5.4 Copper Layer Volume Ratio

The copper layer volume ratio of copper clad aluminum wire should meet the following regulations:
5.4.1 As to 10A and 10H, the copper layer volume ratio should be more than 8% and less than 12%.
5.4.2 As to 15A and 15H, the copper layer volume ratio should be more than 13% and less than 17%.

5.5 DC Resistivity

The DC resistivity of the copper clad aluminum wire at 20 ? should meet the specified value in Table 2.

5.6 Tensile Strength & Extensibility

The tensile strength and extensibility should meet the specified value in Table 1.

5.7 Copper Layer Compactness

When the copper clad aluminum wire is on testing according to 6.6, there should not appear any destructive and constant cracks at the copper layer.

5.8 Copper & Aluminum Adhesiveness

When the copper clad aluminum wire is on testing according to 6.7, there should not be delamination at the interface between the copper layer and the aluminum core wire.

5.9 Nominal Density

Density is taken as one of the items if it is required in the procurement contract. The nominal density and its deviation at 20 ? should meet the specified value in Table 3.

6 Test Method

6.1 Appearance Inspection

As to the copper clad aluminium wire whose diameter is equal to or larger than 1.83mm, we can examine its appearance quality with normal eyesight, otherwise we can do that with a magnifier whose magnification is not more than 10.

6.2 Diameter & Deviation

The diameter of copper clad aluminum wire should be measured according to GB/T4909.2 .

6.3 Copper Layer Thickness & Volume Ratio

The thinnest spot of the copper layer or the copper layer volume ratio should be measured adopting Section Polishing Measurement. Cut down some copper clad aluminum wire in proper length from the sample, after grinding and polishing the section, measure the copper layer thickness using a reading microscope with enough accuracy at the four positions showed in picture 1, and the thinnest spot of the copper layer should be one of the four positions to be measured.

Picture 1 Position Fixing of Copper Layer Thickness

The copper layer thickness is the average of the measured values at the four positions, and calculate the copper layer volume ratio according to the expression above.
S=[1-(D-2t)²/D²]*100%................(1)
in the expression:S-copper layer volume ratio;
D-copper clad aluminum wire diameter(mm);
t-copper layer average thickness(mm).

6.4 DC Resistivity

The DC resistivity of copper clad aluminum wire should be measured according to GB/T 3048.2.

6.5 Tensile Strength & Extensibility

The tensile strength and extensibility test of copper clad aluminum wire should be conducted according to GB/T 4909.3 and also should meet the following regulations:
• The original gauge length is 250mm;
• The tensile speed should be less than 75 mm/min;
• The point of fracture should appear within 25mm from the clamp, and the extensibility test is invalid if the measured value is less than the specified value in this standard.

6.6 Copper Layer Compactness

The copper layer compactness test should be conducted according to GB/T 4909.4. Cut down some copper clad aluminum wire in proper length from the sample, clamp and tense it at the spot 15 times of the nominal diameter, twist three cycles along one direction, then another three cycles along the negative direction. You can do the test with a longer sample and increase the torsion cycles accordingly. The torsion speed is not regulated.

6.7 Copper & Aluminum Adhesiveness

The copper & aluminum adhesiveness test of copper clad aluminum wire should be conducted according to GB/T 4909.5. Conduct the bending test repeatedly untill the sample is fractured. Examine whether there is delamination between the copper and the aluminum core wire with normal eyesight.

6.8 Density

Choose a straight and flat sample of about 100mm long, measure its dimeter and length according to GB/T 4909.2 to calculate the volume, then measure its weight with a balance whose accuracy is 1mg. Then we can calculate the density.
• Test Rules
The finished copper clad aluminum wire can't get out the factory untill being inspected by relative quality inspection department with quality inspection license on it.

7.1 Testing

• Test Items
Test items are specified in Table 4.

Table 4 Test Items

7.2 Receiving Inspection after Packaged (omitted)

8 Packing, Mark, Transport, Storage & Direction for Use
8.1 The copper clad aluminum wire shoud be supplied in disks or coils, well coiled and perfect packaged. Each disk or coil should be one single line without any joint. When it is formed to disk, the last layer should keep proper distance from the disk external. When it is formed to coil, we should bundle at three positions. Special requirements are also accepted.
8.2 There should be a label or tablet on each disk or coil with the following items on it:
• Production unit name or trademark;
• Model;
• Date of production;
• Gross weight and net weight;
• Lot identification mark;
• Inspector's stamp;
• This standard's code number.
8.3 Moisture, corrosion and any damage to the copper clad aluminum wire in general handling, lifting, stacking and transportation should be prevented. The packing materials should meet relative requirements and there should be relative marks on external packing.
8.4 The copper clad aluminum wire should be well stored in dry, breezy, rainproof and waterproof stock house without acid, alkaline matters or harmful gases inside.
8.5 Direction for Use
• Application Area;
• Notice?
• Procurement contract contents.
The procurement contract should contain the following contents:
• Model and quantity;
• Packaging requirement;
• Inspection requirement and place;
• Delivery date and place;
• Else.

App. A

(Promoted appendix)
Copper Clad Aluminum Wire HF Skin Depth Property
Thinnest copper layer thickness of coaxial cable's general copper clad aluminum wire and the result of the skin depth when transmitting signal of 5~100MHz are showed in Table A1.

Table A1