GB 4909.12-1985 Test methods for bare wires - Solderability test of coatings - Solder ball method

This test method is suitable for testing the wettability of tinned copper wire surface by molten solder, which is expressed in a specific time. GB 4909.12-1985 Bare wire test method Plating solderability test Solder ball method GB4909.12-1985 Standard download decompression password: www.bzxz.net

National Standard of the People's Republic of China
Test methods for bare wires
Solderabillty test of coatlngSolder globule method
The provisions of this standard are consistent with the provisions of IEC68-2-20 (1977) for solder globule removal. 1 Scope of application
UDC 621.815.14
:620.179.2
GB4909,12—B5
1.1 This test method is applicable to testing the characteristics of the surface of tinned wire being wetted by molten solder, which is expressed by a specific time. 1.2 The solder globule method is to make the sample divide the solder globule of molten solder into two halves, and measure the time required for the sample to cut the solder globule and the solder to flow around the sample and cover the sample. This time indicates the solderability of the sample. Test equipment
2.1 Weldability test device as shown in Figure 1.
2.1.1 The design and processing of the test device should ensure that the temperature of the heating head is maintained at 235 ± 2 ° C. 2.1.2 The heating body is shown in Figure 2.
The heating body should be made of unheat-treated aluminum rod, its tensile strength should not be less than 170N/mm, and its chemical composition is shown in Table 1.
The diameter of the part of the winding electric heating element is 16.0mm, and the length of this part can be adjusted, but it should not exceed 60mm. b.
The center position of the sensor relief hole should be aimed at the circumferential surface of the heating head, so that the sensor can be inserted into the cylindrical surface of the heating head. The size of the hole should be adapted to the sensor.
National Bureau of Standards 1985-01-31 Issued
1985-12-01 Implementation
GB4909.12--85
Figure 1 Solder ball test device
1-Insulation: 2-Electric heater: 3-Temperature sensor hole punched + 4-Solder ball 5-Heating head, 6 Heating body: 7-Automatic temperature control device: 8 Heater lead, 9-Thermostat, 10 Temperature control device lead 45" angle
GB4909.12-85
Dimensions are in mm, unless otherwise specified, the error is ±0.1. Figure 2 Heating body
1-Sensor placement hole; 2-Heating head placement hole, drilled and dumped, center 3,96 ±0.02 mm; R-a part cut off for placing components
Element name
Iron, manganese, chromium, zinc
or other fine oxidizing elements
Content%
The rest
2.1.8 The heating head is shown in Figure 3.
GB 4809.12-B6
Made of iron, its chemical composition is shown in Table 2.
Element name
Contains the most%
Figure 3 Heating head
Element name
Other impurities
Content%
15 × 10 - f
The rest
b. When installed on the heating body, the heating body should be heated to about 500C, and then the end face of the heating body and the arc surface at R should be polished. c. The top surface of the heating head must be tinned.
2.1.4 Sample clamp
Any simple device can be used to place the sample into the solder ball, but the insulating clamp of Figure 4 is recommended. Figure 4 Sample clamp
1-Insulating block; 2-Sample
2.2 Solder
2.2.1 Chemical composition (weight percentage) is shown in Table 3. The content of other impurities (such as lead, zinc or etc.) outside Table 3 should not exceed the level that has a harmful effect on the performance of the solder. Table 3
Element name
Content%
59 ~ 61
Element name
Contains %
2.2.260%The melting temperature range of solder is: Full solidification 183℃
Full liquefaction 188℃Www.bzxZ.net
2.3.1Rosin should meet the following requirements:
Color standard Rosin color (WW) or whiter
Acid value 155mg per gram of rosin cloth
Softening point (ball and ring)>70℃
Flow point (Eblob)>76℃
GB490$.12—85
Put rosin in When the weight of 2-propanol (isopropanol) is added, the solution should be clear. After being placed at room temperature for one week, the solubility
should not have any precipitation phenomenon.
2.3.22-propanol should meet the following requirements;
Purity should contain at least 99.5% of 2-propanol (isopropanol) by weight Acetic acid acidity (excluding carbon dioxide) by weight Maximum X0.002% Non-flammable components <2mg/100ml
2.3.3 Alcohol should meet the following requirements:
Purity should contain at least 96.2% of alcohol by weight Free acid (excluding carbon dioxide) by weight Maximum 4mg/l. 3 Sample preparation
3.1 The sample length is 100mm.
3.2 The sample should be straight and the test surface should not be directly touched by hand. 3.3 Before the solderability test, the sample is not cleaned. Test steps
4.1 Preparation of flux
4.1.1 The inactive flux is composed of 25% rosin and 75% 2-propanol (isopropanol) or alcohol. 4.1.2 When using active flux, it can be made according to the following formula: Rosin
2-propanol (isopropanol) or alcohol 75g
Ethylamine hydrochloride
Activate with 0.5% chlorine
4.2 Before placing a new solder ball on the heating head of the soldering device 1:, the solder left on the heating head in the previous test should be wiped clean. 4.3 The weight of the solder ball should comply with the requirements of Table 4. Table 4
Nominal diameter of sample d mm
0.24×.d0.54
0.54d<0.74
4.4 When heating the solder ball, the temperature of the heating head should be kept stable at 235±2℃. Nominal weight of solder ball mg
GB 4909.12—85
4.5 Add a small amount of flux to the molten solder ball to ensure that the solder ball is clean and not oxidized, and can completely wet the heating head. 4.6 Place the sample on the sample clamp, apply flux on the surface of the sample, then put the sample into the solder ball, divide the solder ball into two parts, make the sample contact the surface of the heating head, start timing, and stop timing when the solder flows along the surface of the sample to cover the sample, and record the time from the start timing to the end timing.
4.7 Two points should be measured for each sample, and the distance between the points should not be less than 8mm. 4.8 Record the welding time for each point, which should not exceed 2s. 5 Test results and calculations
5.1 The test results are the arithmetic mean of the test data of 8 samples. 5.2 If all 8 samples are qualified, the solderability of the coating of the batch of products is judged to be qualified. If 3 or more samples are unqualified, they should be checked piece by piece. If 2 or less samples are unqualified, 8 samples should be randomly selected from the remaining packaging units of the batch for retesting. If there are still unqualified ones, they should be checked piece by piece. 6. Precautions
6.1 After completing the test, the hot mold should be cooled together with the port ball placed in the working position to prevent oxidation of the heating head and subsequent weak swelling.
B.2 Other test devices can be used, but the following requirements should be met. 6.2.1 The temperature of the heating head should be maintained at 235±2℃. 6.2.2 The temperature of the solder ball is measured by placing a thermocouple with a volume not greater than 0.2 mm2 (such as nickel-chromium-nickel or chromium-nickel-aluminum-nickel thermocouple) in the solder ball.
6.2.3 The sample is a newly tinned copper wire with a diameter of 0.8 mm and a length of 50±2 mm. The sample is clamped with a fixture that minimizes the heat conduction of the sample, and then the sample is inserted into the solder ball. At this time, the following conditions should be met: in the seven repeated tests, at least five times the temperature is not lower than 222°C after 3s.
At any time during the entire test, the temperature should not be lower than 210°C. Additional remarks:
This standard was proposed by the Ministry of Machinery Industry of the People's Republic of China. This standard is under the jurisdiction of the Shanghai Cable Research Institute of the Ministry of Machinery Industry. This standard was drafted by the Shanghai Cable Research Institute of the Ministry of Machinery Industry and others. The person in charge of drafting this standard is Fan Man'e.
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