可焊性wettingbalance

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1、1 Wetting Balance Instrument(MUST System-II)It can be used for study of below:Printed circuit boardsSurface treatment metalsFluxesSolder alloysCleansers2The Wetting Balance_Must System II3The Wetting Balance_Must System IISolderability of Metals4The Wetting Balance_Must System IISolderability on dif

2、ferent surface-Solder on Oxidised21 Copper5The Wetting Balance_Must System IISolderability on different surface-Solder on Clean Copper6The Wetting Balance_Must System IIWetting Forces Formula7The Wetting Balance_Must System IIWetting Forces Formula:For wetting to occur,the contact angle Theta Be les

3、s than 90 degree.8The Wetting Balance_Must System IIWetting Process9The Wetting Balance_Must System IIWetting Processrlv=surface tension of Flux/Molten solder(0.4 mN/mm)c =specimen perimeter(mm)=contact angle g =gravitational acceleration(9.81m/s2)=solder density(8 mg/mm3)v =specimen immersed volume

4、(mm3)10The Wetting Balance_Must System IIWetting Curvea)Sample reach the surface of the solder bathb)Sample at end of immersion depth Achimede pushc)Forces at Equilibriumd)Maximum Wetting forcee)Sample lift out of the solder bathf)Sample is out of the solder bath11The Wetting Balance_Must System IIW

5、etting Curveis reckoned directly from the force(F)measured.F+.v.g COS=-rlv.cNote:The wetting contact angle applies only to liquid solder.The angle is fully representative of the quality of wetting(or solderability).030 very good wetting 3040 good wetting 4055 acceptable wetting 70 very poor wetting

6、12The Wetting Balance_Must System IIWetting Angle Analysis13The Wetting Balance_Must System IIQuantitative Measurement By ST60 The result are expressed in quantitative units Capillary wetting forces(mN)wetting meniscus angle()14The Wetting Balance_Must System IIThe Compliant of ST60Fully compliant w

7、ith standards-NF A 89400-NF C 90550-MIL STD 883 D-IEC 68-2-69-DIN 2506-JIS 5033-IPC J-STD 002 A15The Wetting Balance_Must System IIMeasurement ApplicationMeasurements can be done on the following samples:following samples:Rectangular sample JLCC,PLCC,CCQPJ,SOJ Cylindrical sample 4 Sides output chip

8、22.20 Multi Rectangular leads DUPONT connector solder resist Multi Cylindrical leads PC Board Strip Plated Substrate Single Side Diode D04 Plated Substrate Double Side Diode D05 Chip Capacitor Chip solid Tantale A Chip Resistor Chip solid Tantale B Limited LC04/04 case Chip solid Tantale C SOT 23 Test Solder Paste SOT 143 Test Solder Paste Flat Pack,MQFP100,PQFP,SO CQPL,MQFP 100 SOT89 PCB(Plated Hole&Test Strip)DPACK package Sample(PBRC/AVX 4M)Cylindrical Resistor Chip Film(LCC)