GB/T 2423.28-1982 Basic environmental testing procedures for electrical and electronic products Test T: Soldering test method
Some standard content:
National Standard of the People's Republic of ChinawwW.bzxz.Net
Basic environmental testing
procedures forelectric and electronic productsTest T: soldering
This standard is equivalent to the international standard IEC68-2-20 (1979) Test T: soldering. UDC 621.3: 620.1
GB 2423.28-82
Editorial changes made to this standard include: '2-ol (iso-ol) in the original text is called 'iso-ol according to the domestic standard. The figure numbers in the appendix are originally numbered consecutively with the figures in the text, but now they are changed to the number of the appendix. Supplementary parts are added under each appendix. Figure D3 and Figure E1 were originally drawn by the third angle projection method, but now they are drawn by the first angle projection method. This standard has the same technical content as IEC68-2-20. 1 Scope
This standard applies to all electrical and electronic components that may be subjected to the following test conditions. 2 Purpose
To determine the ability of component terminals and printed circuits to be easily wetted and to check the ability of the components themselves to not be damaged during assembly and soldering.
3 Terminology
3.1 Rosin
Natural rosin is the residue after turpentine is extracted from the oleoresin of pine trees. It is mainly composed of rosin acid and similar resin acids, and also includes a small amount of resin acid esters.
3.2 Contact angle
Usually refers to the angle between the tangent surface of the liquid and the liquid interface at the intersection of liquid and solid (see Figure 1). Here it specifically refers to the contact angle when liquid solder contacts the solid metal surface. Contact angle
3.3 Wetting
National Bureau of Standards, 1982.09-23, issued
1983-06-01, implemented
GB 2423.28--82
The solder forms an adhesion layer on the surface. A small contact angle indicates good wetting. 3.4 Non-wetting
The solder cannot form an adhesion layer on the surface. In this case, the contact angle is much greater than 90°. 3.5 Weak wetting
The molten solder shrinks back to the solid surface area that was wetted at the beginning. In some cases, a very thin solder film may remain. When the solder shrinks, its contact angle increases. 3.6 Solderability
The property of a surface being easily wetted by molten solder. 3.7 Soldering time
The time required to wet a specified surface area under specified conditions. 3.8 Resistance to Soldering Heat
The ability of the test specimen to withstand the thermal stress generated by soldering. 4 Test Ta Solderability of Conductors and Terminals
4.1 Purpose
Determine the solderability of the areas on the conductors and terminals that are required to be wetted by solder. If required, weak wetting is also determined. 4.2 Test Overview
Test Ta provides three different test methods, which are Method 1: Solder bath at 235°C
Method 2: Soldering iron at 350°C
Method 3: Solder ball at 235°C
Weak wetting can be determined by using Method 1 after appropriate changes in time and temperature. The test method to be used should be specified in the relevant standards. The solder bath method is the most similar test method to the commonly used soldering procedures in practice, however, it is not possible to express the test results quantitatively. Solder ball method, ... - a round conductor terminal test specimen is evenly divided into a small ball of molten solder of a given weight. This method is easier to use and uses the soldering time as the inspection standard.
When the above two methods are not feasible, the soldering iron method can be used. If the relevant standard requires accelerated aging before the test, the relevant standard can specify one of the following aging procedures:Aging method 1a: 1 hour steam aging testAging method 1b: 4 hours steam aging testAging method 2: 10 days constant humidity test (test Ca)Aging test 3: 16 hours high temperature test at 155℃ (test Ba)4.3 Preparation of test samples
4.3.1 The surface of the test sample to be tested should be in the same condition as "just received" and should not be touched by fingers or otherwise contaminated thereafter.
4.3.2 The test sample should not be cleaned before the solderability test. If required by the relevant standard, the test sample can be immersed in a neutral organic solvent at room temperature to remove oil. 4.4 Initial inspection
The test sample must be visually inspected, and the electrical and mechanical properties should be inspected if required by the relevant standard. 4.5 Accelerated aging
If the relevant standard requires accelerated aging, one of the following procedures shall be used. Note: If the aging temperature is higher than the maximum operating temperature or storage temperature of the component, or the component is likely to deteriorate significantly in 100°C steam, and this effect on solderability does not usually occur in natural aging, it is allowed to remove the lead for testing. 4.5.1 Aging method 1:
GB 2423.28--82
The relevant standard should clearly specify whether aging method 1a (1 hour in steam) or aging method 1b (4 hours in steam) is used. In these aging procedures, the test sample is suspended above boiling distilled water, and the lead is preferably in a vertical state. The tested area is 25 to 30 mm from the surface of the distilled water. The distilled water is contained in a borosilicate glass or stainless steel container of appropriate size (for example, a 2-liter beaker). The distance between the lead and the container wall should not be less than 10 mm. The container must be covered with a cover consisting of one or more plates made of the same material as the container. It can cover about seven-eighths of the total knocked-open area. An appropriate method for hanging the test sample should be designed, and it is allowed to perforate or slit the cover for this purpose. The fixture of the test sample should be non-metallic.
The water surface is kept at a certain position by adding hot distilled water. It should be added gradually in small amounts so that the water is always boiling. In order to reduce the evaporation of water, a reflux condenser can be installed (see Appendix A Figure A1). 4.5.2 Aging method 2
In accordance with GB2423.3-81 "Basic Environmental Test Procedures for Electronic Products Test Ca: Steady Humidity Test Method", the test sample is subjected to a 10-day steady humidity test.
4.5.3 Aging method 3
According to Test Ba in GB2423.2-81 "Basic environmental test procedures for electrical and electronic products Test B: High temperature test method", the test sample shall be subjected to a high temperature test at 155℃ for 16 hours. 4.5.4 At the end of the aging test, the test sample shall be placed in normal atmospheric conditions for no less than 2 hours and no more than 24 hours. 4.6 Test method 1 (solder bath at 235℃) Here is a procedure for evaluating the solderability of wires, lead terminals and irregularly shaped lead terminals. 4.6.1 Description of solder bath
The depth of the solder bath shall not be less than 40 mm and its volume shall not be less than 300 ml. The solder bath shall contain solder as specified in Appendix B. The temperature of the solder in the bath shall be 235±5℃ before the test. 4.6.2 Flux
As specified in Annex C, the flux used is composed of 25% rosin and 75% isopropyl alcohol or alcohol by weight. When inactive flux is not suitable, diethylamine hydrochloride (analytical grade) may be added to the above flux in accordance with the requirements of the relevant standards. The chlorine content is raised to 0.5% (expressed as free chloride ions based on the rosin content). 4.6.3 Procedure
Before each test, the surface of the molten solder should be scraped clean and bright with a piece of suitable material. The test should be carried out immediately after scraping.
At room temperature, the lead-out terminal to be tested is first immersed in the flux specified in 4.6.2. Excess flux can be dripped by hanging for a suitable time or by any other method that can produce the same effect. In case of dispute, the drip-drying time should be 1 minute ± 5 seconds.
Then immediately dip the lead into the solder tank in the longitudinal axis direction. The distance between the lead's immersion point and the tank wall should not be less than 10 mm.
The immersion speed should be 25±2.5 mm/s, and the lead should remain immersed in the tank for 2.0±0.5 seconds. At the same time, the body of the component should maintain a distance from the solder as specified in the relevant standards. The test sample is then removed at a speed of 25±2.5 mm/s. For components with large heat capacity, the relevant standards may specify an immersion time of 5.0±0.5 seconds. If required by the relevant standards, a baffle made of insulating material with a thickness of 1.5±0.5 mm can be used between the component body and the molten solder, with a hole corresponding to the size of the lead. Any flux residue should be removed using isopropyl alcohol or alcohol. 4.6.4 Requirements
A visual inspection shall be carried out, which can be done by naked eye observation under suitable light or with the aid of a 4-10x magnifying glass. The dipped surface must be covered with a smooth, bright layer of solder, with only a few scattered defects such as pinholes, non-wetting or weakly wetted areas allowed, and these defects should not be concentrated in one place. 4.7 Test method 2 (soldering at 350°C) 286
GB 2423.28-82
Where the solder bath or solder ball method cannot be used, this test method may be used to assess the solderability of the lead-out. 4.7.1 Description of soldering iron
Tip temperature: 350 ± 10 °C (at the start of the test) Tip diameter: 8 mm
Exposed length: 32 mm, wedge length approximately 10 mm Type B
Tip temperature: 350 ± 10 °C (at the start of the test) Tip diameter: 3 mm
Exposed length: 12 mm, wedge length approximately 5 mm The tip shall be made of copper (preferably plated with iron) or of a corrosion-resistant copper alloy in accordance with common practice and tinned on the test surface.
4.7.2 Solder and flux
Rosin core solder wire shall be used, consisting of solder as specified in Appendix B and a single core with rosin as specified in Appendix C containing 2.5% to 3.5%. Visual inspection shall be carried out during the test to determine the presence of flux. 4.7.3 Procedure
A soldering iron of size A or B shall be used, depending on the type of component, as specified in the relevant standard. The nominal diameter of the soldering wire used shall be 1.2 mm for the A soldering iron and 0.8 mm for the B soldering iron.
The terminals shall be placed so that the surface of the soldering iron to be tested is in a horizontal position, as shown in Figure 2. Soldering iron tip
Component
Solder wire: sufficient to cover the test surface
Terminals
If the terminals are to be mechanically supported during the test, this support shall be made of thermally insulating material. When testing heat-sensitive components, the relevant standard shall specify the distance between the test area and the component body or the use of a specific heat sink. When the geometry of the terminals makes it impossible to perform the test according to the above procedure, the relevant standard may specify different test conditions.
Excess solder left on the surface of the soldering iron from previous tests must be removed. Unless otherwise specified, the time for applying the soldering iron and solder to the terminal position specified in the relevant standard shall be 2 to 3 seconds. The soldering iron shall remain motionless during this period.
Any flux residue shall be removed with isoresin or alcohol. 4.7.4 Requirements
A visual inspection shall be carried out, which may be done by visual inspection under suitable lighting or with the aid of a 4 to 10 times magnifying glass. The solder shall wet the test surface area and shall not have droplets. 4.8 Test Method 3 (Solder Ball at 235°C) A procedure for measuring the soldering time of round conductor terminals is provided here. 287
4.8.1 Method
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The apparatus described in Appendix D is designed so that the wire divides the molten solder ball into two halves. The time from the time the wire cuts the solder ball to the time the solder flows around the wire and covers the wire is measured. This time indicates the solderability of the wire. 4.8.2 Test Conditions
4.8.2.1 Solder
As shown in the Appendix, the relationship between the solder ball and the wire diameter is as follows: Nominal wire diameter
(mm)
0.74~0.55
0.54~0.25
Note: For the allowable deviation of the nominal weight, see B3 of Appendix B. 4.8.2.2 Temperature of the heating head
Nominal weight of the ball
(Jacques)
The device should be adjusted so that when the temperature is measured by the method shown in Figures D1 and D2 of Appendix D, the temperature is maintained at 235±2℃. 4.8.2.3 Flux
As specified in Appendix C, the flux used should consist of 25% rosin and 75% isopropyl alcohol or alcohol by weight. When inactive flux is not suitable, diethylamine hydrochloride (analytical grade) may be added to the above flux to raise the chlorine content to 0.5% (expressed as free chloride ion based on the rosin content) as required by the relevant standard. 4.8.3 Procedure
The test wires shall be substantially straight and, if necessary or convenient, may be removed from the test specimens to be tested.
The wires shall not be cleaned before solderability testing. If required by the relevant standard, the wires may be soaked in a neutral organic solvent at room temperature to remove oil. Before placing a new solder ball selected in accordance with 4.8.2.1 on the heating head of the soldering apparatus, the solder left on the heating head from the previous test shall be wiped clean.
The flux shall be applied by dipping the wire in the flux or by brushing the flux onto the wire placed in the appropriate position in the test apparatus. A small amount of flux may also be applied to the molten solder ball to ensure that it is clean and not oxidized and that it can completely wet the heating head. The wire to be tested is then placed in the ball so that the wire contacts the surface of the heating head. 4.8.4 Requirements
Measure the time from the wire cutting the solder contacting the heating head to the solder flowing around the wire and covering the wire. This is the welding time. The maximum value of the welding time should be specified in the relevant standards. 4.9 Weak wetting
Note: The relevant standards should specify whether this test is required. 4.9.1 Description of solder tank
The depth of the solder tank should not be less than 40 mm and its volume should not be less than 300 ml. The solder tank should contain the solder specified in Appendix B. The temperature of the solder in the tank should be 260±5℃ before the test. 4.9.2 Procedure
Before each test, the surface of the molten solder should be scraped clean and bright with a piece of suitable material. The test should be carried out immediately after scraping.
At the test room temperature, first immerse the tested terminal in the flux specified in 4.6.2. Excess flux can be removed by dripping for an appropriate time or by any other method that can produce the same effect. In case of dispute, the dripping time should be 1 minute ± 5 seconds.
GB 2423.28 -82
Then immediately immerse the lead-out terminal into the soldering tank in the direction of the longitudinal axis. The distance between the immersion point of the lead-out terminal and the tank wall should not be less than 10 mm.
The immersion speed should be 5±2 mm/s, and the lead-out terminal should remain immersed in the tank for 5.0±0.5 seconds. At the same time, the body of the component should maintain a distance from the solder as specified in the relevant standards. Then remove the test sample at the same speed. When removing it from the solder tank, the test surface of the lead-out terminal should be kept vertical until the solder solidifies. Any flux residue should be removed with isopropyl alcohol or alcohol. 4.9.3 Requirements
A visual inspection should be carried out, which can be observed with the naked eye under appropriate light or with the aid of Check with a magnifying glass of 4 to 10 times. The dipped surface must be covered with a smooth and bright solder layer. Only a small amount of scattered defects such as pinholes, non-wetting or weak wetting areas are allowed, and these defects should not be concentrated together. 4.9.4 Secondly, the above test should be repeated. Because weak wetting may occur very slowly, a total of 10 seconds of immersion is required. This immersion can be divided into two 5-second cycles so that any rapid weak wetting is not covered up by any subsequent rewetting. 4.10 Final test
The test sample should be visually inspected. If required by the relevant standards, electrical and mechanical properties should be checked. 4.11
Regulations that should be made in relevant standards
When the relevant standard covers this test, the following details should be given until applicable: a.
Whether degreasing is required
Initial inspection
Aging method (if required)
Test method
Whether active flux is used
Depth and time of immersion (if not 2 seconds)Whether a heat shield is used
Soldering iron number (A or B)
Distance of test area from component body or heat sink usedDifferent test conditions required due to the geometry of the lead-outsPosition of soldering iron
Time of use of soldering iron (if not 2 to 3 seconds)Soldering time||t t||Is a weak wetting test required?
Immersion depth
Final test
Test Tb component resistance to soldering heat
5.1 Purpose
Determine the ability of the test sample to withstand the thermal stress generated by soldering. 5.2 Test Overview
Three different test methods are proposed here, which are: Test Method 1A: Solder bath at 260°C Test Method 1B: Solder bath at 350°C Test Method 2: Soldering iron at 350°C (see 4.3.2, 4.8.3)
(see 4.4)
(see 4.5)
(see 4.6, 4.7 or 4.8)
(See 4.6.2, 4.8.2.3)
(See 4.6.3, 4.9.2)
(See 4.6.3)
(See 4.7.3)
(See 4.7.3)
(See 4.7.3)
(See 4.7.3)
(See 4.8.4)
(See 4.9)
(See 4.9.2)
(See 4.10)
Methods 1A and 1B are the same as Test Ta Method 1, but different immersion times and temperatures are used. Method 2 is the same as Test Ta Method 2, but the soldering iron is applied to the test surface for 10 seconds. 289
5.3 Initial inspection
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According to the relevant standards, the test samples shall be inspected for appearance, electrical properties and mechanical properties. 5.4 Test method 1A (soldering tank with a temperature of 260°C) 5.4.1 Soldering tank
The depth of the soldering tank shall not be less than 40 mm and its volume shall not be less than 300 ml. The soldering tank shall contain the solder specified in Appendix B. The temperature of the solder in the tank shall be 260±5°C before the test. 5.4.2 Flux
5.4.2.1 The flux used shall consist of 25% by weight of rosin and 75% by weight of isopropyl alcohol or spirit, with diethylamine hydrochloride (analytical grade) added to bring the chloride content up to 0.5% (expressed as free chloride ion based on the rosin content). 5.4.2.2 When the test is part of a complete test series and is made before the damp heat test, an inactive flux consisting of 25% by weight of rosin and 75% by weight of isopropyl alcohol or spirit shall be used. In this case, the test shall be made on the following test specimens which have been satisfactorily tested for solderability in Test Ta Method 1 within 72 hours. 5.4.3 Procedure
Before each test, the surface of the molten solder shall be scraped clean and bright with a piece of suitable material. The test shall be made immediately after scraping.
The terminals to be tested shall first be immersed in the flux specified in 5.4.2 at laboratory temperature and then immersed in the solder bath in the longitudinal direction. The immersion point of the terminals shall be at least 10 mm away from the tank wall. Unless otherwise specified in the relevant standards. The terminals shall be immersed in a time not exceeding 1 second to a distance of 2.0 to 2.5 mm from the components or mounting surface. The terminals shall be immersed at the specified depth for one of the following durations specified in the relevant standards: a. 5 ± 1 second,
b. 10 ± 1 second.
Note: The shorter immersion time of 5 seconds is mainly intended for heat-sensitive components mounted on printed circuit boards. The user must be reminded that such components must be soldered to the printed circuit board within 4 seconds. Unless otherwise specified in the relevant standard, a baffle made of insulating material with a thickness of 1.5 ± 0.5 mm shall be placed between the component body and the molten solder, with apertures corresponding to the size of the lead terminals. When the relevant standard specifies the use of a heat sink during the test, details of the size and type of heat diverter used shall be given, and all these details shall be related to the method used in the product soldering. 5.5 Test Method 1B (Soldering Bath at 350°C) 5.5.1 Soldering Bath
The soldering bath shall be the same as that specified in 5.4.1, but its temperature shall be 350 ± 10°C. 5.5.2 Procedure
The procedure shall be the same as that specified in 5.4.3, but the immersion time shall be 3.5 ± 0.5 seconds. The entire immersion process, including the stay in the bath and the removal, shall be completed in a time of not less than 3.5 seconds and not more than 5 seconds. 5.6 Test Method 2 (Soldering Iron at 350°C) 5.6.1 Description of Soldering Iron
As specified in 4.7.1.
The relevant standard shall specify whether to use A or B soldering iron. 5.6.2 Solder and Flux
As specified in 4.7.2.
5.6.3 Procedure
As specified in Test Ta 4.7 Method 2 Soldering Iron. However, the time of using the soldering iron on the test surface of the lead is 10 ± 1 seconds. For heat-sensitive components, the relevant standard shall specify the distance between the test area and the component body, or use a specific heat sink. 5.7 Recovery
Normal atmospheric conditions are specified in the national standard GB2421-81 "General Principles of Basic Environmental Test Procedures for Electrical and Electronic Products". Test 290
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The sample should be restored under normal conditions for 30 minutes or until thermal stability. Note: For some devices, such as semiconductor devices and capacitors, their electrical properties must be stabilized several hours after thermal stability. 5.8 Final inspection
According to relevant standards, the test samples should be inspected for appearance, electrical properties and mechanical properties. 5.9 Provisions to be made in relevant standards
When the relevant standard adopts this test, the following details shall be given until applicable: Initial test
Test method used
(see 5.3)
(see 5.4, 5.5 or 5.6)
Depth of immersion, if the distance from the component body is different from 2.0 to 2.5 mm (see 5.4.3) Smell during immersion
Whether a heat shield is used, if required, specify the details of the heat sink f.
No. of soldering iron Code (A or B)
Distance between component body and test area or use a specific heat sink Final test
6 Test Tc (Solderability of Printed Boards and Copper-clad Laminates) 6.1 Purpose
(See 5.4.3)
(See 5.4.3)
(See 5.6.1)
(See 5.6.3)
(See 5.8)
To determine the solderability of the area required to be solderable on the following items, and include a weak wetting test procedure. String. Single-sided or double-sided copper-clad laminates, b. Single-sided or double-sided printed circuit boards with or without metallized holes: c. Multilayer printed circuit boards.
Note: Each side of the double-sided board should be tested separately. 6.2 Test Overview
Batch soldering of printed circuit board assemblies is a widely used manufacturing process throughout the industry. One method is to use spray soldering or wave soldering. The practice is to fix the printed board on a moving conveyor so that it passes through a standing wave of molten solder. The test procedure described below provides a method for evaluating the difficulty of obtaining a good soldering surface on any particular copper-clad board. This test procedure has good reproducibility.
A rectangular test sample cut from a copper-clad laminate or from a single-sided or double-sided printed circuit board is first coated with flux and then conveyed at a constant speed on an endless conveyor around a horizontal axis so that the test surface is in contact with the molten solder. The time the test sample is in contact with the solder is controlled by a timing device. The wetting or weak wetting characteristics of the test sample are evaluated in accordance with the provisions of the relevant professional standards. 6.3 Test Samples
The test sample shall be a rectangle with a width of 30 ± 1 mm and a length that meets the requirements of 6.4.3.1 and shall be cut from: a. Single-sided or double-sided copper-clad laminates: samples that have not been etched should be used. b. Single-sided or double-sided printed circuit boards with or without metallized holes: a portion of a suitable typical test pattern is given in the relevant professional standards.
Multilayer printed circuit boards: To be determined.
Test samples b. and c. should be manufactured at the same time and under the same conditions as the batch production of printed circuit boards. When test samples b. and c. are not cut from any standard test pattern, conductor width, insulation gap, welding area, holes and thermal shunting effects should be taken into account. Test samples should not include conductor structures that may affect the evaluation of solderability, etc. We do not intend to prove whether a particular design of board is easy to solder, but to select samples to test the solderability of copper or clad metal layers. 6.4 Test equipment
6.4.1 Welding groove
A suitable welding groove with a depth of not less than 40 mm should be used. If the welding groove is round, its diameter should not be less than 120 mm. If the welding groove is rectangular, it should not be less than 100 mm × 75 mm.
6.4.2 Transport of test sample
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A mechanical device transports the test sample at a constant speed around the horizontal axis on a circular channel so that the test surface contacts the molten solder. When no stop is made during contact with the solder, the rotation radius should pass vertically through the center of the test sample surface. The distance between the test surface and the rotation axis should be 100±5 mm (the outline diagram in Appendix E shows the recommended arrangement of the test sample fixture and timing needle). The rotation speed range should be adjustable so that the time the test sample is in contact with the solder (as in 6.4.4) in the range of 1 second to 8 seconds.
When the board is in a horizontal position, the depth of immersion of the test surface in the molten solder should not exceed the thickness of the board. It is important to ensure that the solder does not flow over the upper surface of the test specimen. Therefore, it is permitted to use a sample fixture equipped with a frame to avoid this phenomenon (see 6.4.3).
6.4.3 Test sample fixture
Whatever type of sample fixture may be used, provided that it can hold the test specimen as specified above (see also Annex E) and meets the following requirements:
a. The exposed length of the test surface of the test specimen in the direction of movement shall be 25 ± 1 mm. b. Those parts of the sample fixture (including the retaining spring if installed) that come into contact with the test specimen or the solder shall have low heat capacity and low thermal conductivity. c. The sample fixture shall not in any way hinder the wetting of the exposed surface. 6.4.4 Timing Device
The contact time between the test surface of the test specimen and the molten solder shall be determined by a timer which is triggered by the electrical contact of a needle with the molten solder. The needle tip shall be placed close to the test specimen and have the same axis of rotation and radius of rotation as the center of the test surface of the test specimen. The needle tip shall be insulated from the test specimen holder (see Annex E) which carries it and shall be kept clean during the test. Since the size of the needle can affect the time recorded, each device shall be calibrated before being used. 6.4.5 Cleaning of Solder
In order to remove oxides or flux residues from the solder surface before the test specimen is placed, a narrow strip of suitable material 50 mm wide shall be fixed to the test device in front of the test specimen during the test cycle. The maximum distance of this strip in front of the test specimen shall not exceed 10 mm.
6.5 Solder
The solder bath shall contain solder of chemical composition and melting temperature range in accordance with Annex B. The temperature of the solder in the tank immediately before the test is to be determined by the relevant professional standard. 6.6 Flux
The relevant standard shall specify one of the following three fluxes, the composition of which is as follows: 6.6.1 25% rosin and 75% isopropyl alcohol or alcohol by weight (as specified in Appendix C). 6.6.2 Diethylamine hydrochloride (analytical grade) is added to the flux described in 6.6.1 to obtain a chlorine content of 0.2% (expressed as free chloride ion based on the rosin content). 6.6.3 Flux as specified in 6.6.2, but with a chlorine content of 0.5%. 6.7 Accelerated Aging
If accelerated aging is required before solderability testing, the procedure used shall be specified in the relevant standard. 6.8 Test Procedure
6.8.1 General Requirements
Before solderability testing, the test specimens shall be cleaned in accordance with the procedures specified in the relevant standard. The immersion depth and the operating speed shall be adjusted to the conditions specified in 6.4.2 and 6.8.2 respectively. The test sample shall be prepared in accordance with 6.3 and 6.8.1 and dipped into the flux specified in 6.6 to coat the flux. The test sample shall be dipped vertically into the flux and shaken to allow the flux to flow smoothly into the holes. The holding time at the maximum depth shall be 3 seconds. The test sample shall then be removed vertically at a rate of approximately 5 mm/s. The holes still filled with flux shall be cleared again (this may be done by tapping the test sample). The excess flux may be left to drip dry by placing the test sample vertically for 5 minutes until the flux becomes viscous. The test sample shall be fixed on the test device and the welding test shall be started. 6.8.2 Solderability - Time in contact with solder a. Wetting - The test sample shall be kept in contact with the molten solder for an appropriate time as specified in the relevant professional standards. b. The weak wetting test specimen shall be kept in contact with the molten solder for an appropriate time as specified in the relevant professional standards. 6.9 Assessment of solderability and weak wetting
After the test is completed, the excess flux shall be removed with a suitable solvent such as isopropyl alcohol or alcohol. It can be inspected with the aid of a magnifying glass of 8 to 12 times under appropriate lighting. Note: The requirements for solderability and weak wetting and the applicable sampling plan are specified in the relevant professional standards. 6.10 Provisions to be made in the relevant standards
Temperature of solder in the solder bath
Type of flux
If required, specify the accelerated aging method
Cleaning procedure for test specimens
(See 6.5)
(See 6.6)
(See 6.7)
(See 6.8.1)
Cooling water inlet
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Appendix A
Example of an accelerated steam aging apparatus
(Supplement)
Clamp for supporting the flask
A height of about 75 mm and a diameter of about 125 mm
Space for placing the test sample
Test sample
Support for the test sample (porcelain filter disc supported by a glass
rod)
Anti-boiling stones
Note: The test sample should not be placed in the lowest part of the cooling flask because of dripping water. 294
Cooling water out of the mountain
Borosilicate glass flask with a capacity of 2 liters
Filtration with loose-fitting glass fiber
Beaker spout plugged with paper roll
Borosilicate glass beaker with a capacity of 2 liters
800 cubic centimeters of deionized water
750 W electric furnace with power regulator
The solder used should meet the following requirements:
B.1 Chemical composition
The composition calculated by weight percentage is as follows: Tin
GB 2423.28—82
Appendix B
Solder Specifications
(Supplement)
From 59% to 61%
Up to 0.5%
Up to 0.1%
Up to 0.05%
Up to 0.02%
The remainder
Impurities such as aluminum, zinc or the like shall not be present in the solder in an amount that would adversely affect the properties of the solder. B.2 Melting Temperature Range
The melting temperature range for solder containing 60% tin is as follows: 183°C
Fully solidified
Fully liquefied
188°C
Weight of solder balls during solder ball test (Method 3) B.3
The number of solder balls exceeding ±10% of the nominal weight shall not exceed 1.5%. 2952% (expressed as free chloride ions based on the rosin content). 6.6.3 Flux as specified in 6.6.2, but containing 0.5% chloride. 6.7 Accelerated Aging
If accelerated aging is required prior to solderability testing, the procedure used shall be as specified in the relevant standard. 6.8 Test Procedure
6.8.1 General
Before solderability testing, the test specimens shall be cleaned in accordance with the procedures specified in the relevant standard. The immersion depth and operating speed shall be adjusted to the conditions specified in 6.4.2 and 6.8.2, respectively. The test specimens shall be prepared in accordance with 6.3 and 6.8.1 and dipped into the flux specified in 6.6 to coat the flux. The test specimens shall be dipped vertically into the flux and shaken to allow the flux to flow smoothly into the holes. The holding time at the maximum depth shall be 3 seconds. The test sample shall then be removed vertically at a rate of approximately 5 mm/s. The holes still filled with flux shall be cleared again (this may be done by tapping the test sample). The excess flux may be left standing for 5 minutes to drip dry until the flux becomes sticky. Fix the test sample on the test device and start the soldering test. 6.8.2 Solderability - Time in contact with solder a. Wetting - The test sample shall be kept in contact with the molten solder for an appropriate time as specified in the relevant professional standards. b. Weak wetting test sample shall be kept in contact with the molten solder for an appropriate time as specified in the relevant professional standards. 6.9 Evaluation of solderability and weak wetting
After the test is completed, the excess flux shall be removed with a suitable solvent such as isopropyl alcohol or alcohol. It may be inspected under appropriate lighting with the aid of a magnifying glass of 8 to 12 times. Note: The requirements for solderability and weak wetting and the applicable sampling plan are specified in the relevant professional standards. 6.10 Provisions to be made in relevant standards
Temperature of solder in solder bath
Type of flux
If required, specify accelerated aging method
Cleaning procedure for test samples
(See 6.5)
(See 6.6)
(See 6.7)
(See 6.8.1)
Cooling water inlet
GB 2423.28-82
Appendix A
Example of an accelerated steam aging apparatus
(Supplement)
Clamp for supporting the flask
A height of about 75 mm and a diameter of about 125 mm
Space for placing the test sample
Test sample
Support for the test sample (porcelain filter disc supported by a glass
rod)
Anti-boiling stones
Note: The test sample should not be placed in the lowest part of the cooling flask because of dripping water. 294
Cooling water out of the mountain
Borosilicate glass flask with a capacity of 2 liters
Filtration with loose-fitting glass fiber
Beaker spout plugged with paper roll
Borosilicate glass beaker with a capacity of 2 liters
800 cubic centimeters of deionized water
750 W electric furnace with power regulator
The solder used should meet the following requirements:
B.1 Chemical composition
The composition calculated by weight percentage is as follows: Tin
GB 2423.28—82
Appendix B
Solder Specifications
(Supplement)
From 59% to 61%
Up to 0.5%
Up to 0.1%
Up to 0.05%
Up to 0.02%
The remainder
Impurities such as aluminum, zinc or the like shall not be present in the solder in an amount that would adversely affect the properties of the solder. B.2 Melting Temperature Range
The melting temperature range for solder containing 60% tin is as follows: 183°C
Fully solidified
Fully liquefied
188°C
Weight of solder balls during solder ball test (Method 3) B.3
The number of solder balls exceeding ±10% of the nominal weight shall not exceed 1.5%. 2952% (expressed as free chloride ions based on the rosin content). 6.6.3 Flux as specified in 6.6.2, but containing 0.5% chloride. 6.7 Accelerated Aging
If accelerated aging is required prior to solderability testing, the procedure used shall be as specified in the relevant standard. 6.8 Test Procedure
6.8.1 General
Before solderability testing, the test specimens shall be cleaned in accordance with the procedures specified in the relevant standard. The immersion depth and operating speed shall be adjusted to the conditions specified in 6.4.2 and 6.8.2, respectively. The test specimens shall be prepared in accordance with 6.3 and 6.8.1 and dipped into the flux specified in 6.6 to coat the flux. The test specimens shall be dipped vertically into the flux and shaken to allow the flux to flow smoothly into the holes. The holding time at the maximum depth shall be 3 seconds. The test sample shall then be removed vertically at a rate of approximately 5 mm/s. The holes still filled with flux shall be cleared again (this may be done by tapping the test sample). The excess flux may be left standing for 5 minutes to drip dry until the flux becomes sticky. Fix the test sample on the test device and start the soldering test. 6.8.2 Solderability - Time in contact with solder a. Wetting - The test sample shall be kept in contact with the molten solder for an appropriate time as specified in the relevant professional standards. b. Weak wetting test sample shall be kept in contact with the molten solder for an appropriate time as specified in the relevant professional standards. 6.9 Evaluation of solderability and weak wetting
After the test is completed, the excess flux shall be removed with a suitable solvent such as isopropyl alcohol or alcohol. It may be inspected under appropriate lighting with the aid of a magnifying glass of 8 to 12 times. Note: The requirements for solderability and weak wetting and the applicable sampling plan are specified in the relevant professional standards. 6.10 Provisions to be made in relevant standards
Temperature of solder in solder bath
Type of flux
If required, specify accelerated aging method
Cleaning procedure for test samples
(See 6.5)
(See 6.6)
(See 6.7)
(See 6.8.1)
Cooling water inlet
GB 2423.28-82
Appendix A
Example of an accelerated steam aging apparatus
(Supplement)
Clamp for supporting the flask
A height of about 75 mm and a diameter of about 125 mm
Space for placing the test sample
Test sample
Support for the test sample (porcelain filter disc supported by a glass
rod)
Anti-boiling stones
Note: The test sample should not be placed in the lowest part of the cooling flask because of dripping water. 294
Cooling water out of the mountain
Borosilicate glass flask with a capacity of 2 liters
Filtration with loose-fitting glass fiber
Beaker spout plugged with paper roll
Borosilicate glass beaker with a capacity of 2 liters
800 cubic centimeters of deionized water
750 W electric furnace with power regulator
The solder used should meet the following requirements:
B.1 Chemical composition
The composition calculated by weight percentage is as follows: Tin
GB 2423.28—82
Appendix B
Solder Specifications
(Supplement)
From 59% to 61%
Up to 0.5%
Up to 0.1%
Up to 0.05%
Up to 0.02%
The remainder
Impurities such as aluminum, zinc or the like shall not be present in the solder in an amount that would adversely affect the properties of the solder. B.2 Melting Temperature Range
The melting temperature range for solder containing 60% tin is as follows: 183°C
Fully solidified
Fully liquefied
188°C
Weight of solder balls during solder ball test (Method 3) B.3
The number of solder balls exceeding ±10% of the nominal weight shall not exceed 1.5%. 295
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