ISO 9455-16:2013 pdf download.Soft soldering fluxes — Test methods — Part 16: Flux efficacy test, wetting balance method
7 Test pieces
The test pieces shall be made of copper. EXAMPLE Test pieces are cut from a rectangular copper sheet. The dimensions of each test piece are as follows:
— width: 10,0 mm ± 0,1 mm;
— length: constant between 15 mm and 30 mm, to suit the equipment used;
— thickness: either 0,10 mm ± 0,02 mm or 0,30 mm ± 0,05 mm. When testing fluxes of type 1 or 2 (as defined in ISO 9454-1), full details of the test pieces shall be given in the test report.
The sheet or other article used for preparing the test pieces shall be clean and free from contamination. In order to obtain accurate results, the test pieces shall be cut cleanly without leaving significant burrs.
8 Procedure
8.1 Preparation of the test pieces
8.1.1 Cleaning The test pieces shall be handled with clean tongs throughout. Select sufficient test pieces (see Clause 7) to allow 10 per test flux and 10 per standard flux. Degrease them in acetone (5.2) and allow to dry. Immerse them for 20 s in the acid cleaning solution (5.1) at room temperature. Remove the test pieces from the acid cleaning solution and wash for about five seconds under running tap water. Rinse with distilled or deionized water then acetone (5.2) and dry with acid-free filter paper (6.3). If required, the test pieces may be stored in acetone after rinsing them in deionized water. When needed, they shall be removed from the acetone and dried with acid-free filter paper (6.3). Subject all the test pieces to one of the ageing procedures given in 8.1.2 to 8.1.4 as agreed between the flux supplier and the customer.
8.1.2 Ageing the surface by sulfidation process Carry out the procedure given in Annex B on all the cleaned test pieces (see 8.1.1).
8.1.3 Steam ageing the surface Carry out the steam ageing procedure given in IEC 60068-2-20:2008, 4.1.1, ageing procedure 1b, for a period of 4 h on all the cleaned test pieces (see 8.1.1).
8.1.4 Damp-heat, steady-state ageing Subject all the cleaned pieces (see 8.1.1) to the test chamber conditions specified in IEC 60068-2-78:2001, Clause 4, for a period selected from 1 h, 4 h or 24 h.
8.2 Test method
8.2.1 Carry out the following test procedure on each of the 10 test pieces. Complete all 10 tests within 45 min of the preparation stage (see 8.1).
8.2.2 If the flux under test is of type 1 or type 2 (as defined in ISO 9454-1), maintain the temperature of the solder bath at 235 °C ± 3 °C or 255 °C ± 3 °C (see 6.2). When testing fluxes which are not type 1 or type 2 (as defined in ISO 9454-1), the bath temperature requirements and the standard flux to be used for comparison shall be agreed between the flux supplier and the customer.
8.2.3 Remove one of the test pieces from the acetone, dry it between two sheets of acid-free filter paper (6.3) and place it in the wetting balance specimen clip so that the long edges are vertical. Dip the test piece in the flux solution under test at room temperature, to a depth of no less than 3 mm greater than the depth selected for immersion of the test piece in the solder (see 8.2.5). Avoid excess flux by withdrawing the test piece cornerwise from the flux. If excess flux is still visible, touch the corner of the test piece on clean filter paper.
8.2.4 Attach the specimen clip to the wetting balance, ensuring that the bottom edge of the test piece is horizontal and approximately 20 mm above the solder bath (6.2). Allow it to remain there for 20 s± 5 s so that the solvent in the flux can evaporate before the test commences. Some types of flux might require a drying time which is shorter or longer than 20 s± 5 s. In these cases, the drying time shall be agreed between the flux supplier and the customer. During this drying period, adjust the suspension force signal and recorder trace to the desired zero position. Immediately before starting the test, scrape the surface of the solder bath with a blade of suitable material to remove oxides.
8.2.5 Either by raising the solder bath or by lowering the test piece, dip the test piece into the molten solder at a speed of 20 mm/s ± 5 mm/s to a depth of either 3 mm ± 0,2 mm or 4 mm ± 0,2 mm. Hold the test piece in this position for 5 s to 10 s and then withdraw it at a speed of 20 mm/s ± 5 mm/s. Record the wetting force against time for the period during which the test piece is in contact with the solder.
8.2.6 Repeat operations 8.2.2 to 8.2.5 for each of the remaining nine test pieces. 9 Reference value using standard flux Carry out the procedure described in Clause 8 using a further 10 test pieces (see Clause 7) but using a standard flux instead of the flux under test. If the flux under test is of type 1 or type 2 (as defined in ISO 9454-1), the standard flux prepared as described in Annex A may be used. If the flux under test is of type 1.1.1 or 1.2.1 (as defined in ISO 9454-1), use the standard flux prepared as described in A.5.1. If the flux under test is of type 1.1.2, 1.1.3, 1.2.2 or 1.2.3 (as defined in ISO 9454-1), use the standard flux prepared as described in A.5.2. If the flux under test is not of type 1 or type 2, use a standard flux as agreed upon by the supplier and customer (see 8.2.2, second paragraph). 10 Presentation of results A typical trace of wetting force against time is given in Figure 1. In Figure 1, non-wetting (upward) forces are shown as negative and wetting (downward) forces as positive.ISO 9455-16 pdf download.ISO 9455-16-2013 pdf download
