Transcription of Solder Paste—Tack Test
1 ScopeThis test is to determine the ability of a printedpattern of Solder paste to retain a probe placed in the solderpaste by measuring the force required to separate the probefrom the paste. Time between printing and probe placementare progressively increased to simulate variables in a manu-facturing Applicable Test SpecimenA representative sample of this pasteshould then be printed out, using a stencil, onto clean plain-glass slides. At least six paste deposits should be printed perrequired time data-point. The final deposits must be circular, mm in diameter and mm thick. Mark the test speci-men in a suitable manner to identify the sample and the timeafter printing when tackiness is to be measured.
2 The preparedsamples shall be stored at 25 C 2 C and 50 C 10% rela-tive humidity (RH) until evaluated. The samples shall not bestored in an enclosed cabinet or container, which allows thesolder paste solvent vapors to saturate the environment sur-rounding the printed paste, thus preventing natural drying ofthe Equipment/ApparatusA Chatillon tackiness tester orother equipment may be used, providing it is capable of accu-rately measuring force when tested at a similar velocity. Theequipment shall have a stainless steel test probe with a nomi-nal mm mm diameter bottom surface, which issmooth, flat, and aligned parallel to the plane of the subjecttest specimen.
3 The probe shall contact the test specimen at acontrolled speed and apply a controlled, fixed initial contactforce. Finally, a means shall be provided to withdraw the testprobe from the surface of the test specimen at a controlledspeed and record the peak force required to break contactwith the test ProcedurePlace the specimen slide under the testprobe and center the probe over one of the three printed pat-terns. Bring the test probe in contact with the printed pastespecimen at a rate of mm/min. mm/min. and applya force of 300g 30gtothespecimen. Within five secondsfollowing application of this force, withdraw the probe from thespecimen at a rate of mm/min.
4 Mm/min. and recordthe peak force required to break the contact. Take at least fiveadditional measurements under the same test conditions andaverage all the readings. Record both the tack force and timefollowing paste EvaluationInitial measurements are to be taken imme-diately after printing. Subsequent measurements of force shallbe taken as needed to best define the rise and decline of thetack force. Tackiness data should be presented in graph form,provided that the graph with tack force is plotted as a func-tion of time after printing. The data can also be reported asfollows:1. Time to reach 80% of the peak The peak tack force in grams with the expected Time over which the peak value is maintained or for thetack force to decline to 80% of its peak Test Equipment SourcesThe equipment sourcesdescribed in and represent those currently knownto the industry.
5 Users of this test method are urged to submitadditional source names as they become available so that thislist can be kept as current as Somerset DriveLargo, FL 33773 Phone: 1 (800) Instruments Industrial , CA 94545 Phone: 1 (510) 293-0580 The Institute for Interconnecting and Packaging Electronic Circuits2215 Sanders Road Northbrook, IL 60062-6135 IPC-TM-650 TEST METHODS Paste Tack TestDate3/98 RevisionReaffirmedOriginating Task GroupSolder Paste Task Group (5-24b)Material in this Test Methods Manual was voluntarily established by Technical Committees of the IPC. This material is advisory onlyand its use or adaptation is entirely voluntary. IPC disclaims all liability of any kind as to the use, application, or adaptation of thismaterial.
6 Users are also wholly responsible for protecting themselves against all claims or liabilities for patent referenced is for the convenience of the user and does not imply endorsement by the
