J-STD-004B: A New Twist on an Old Standard Ales Sedlak
Outline/Agenda Introduction How Are Flux Properties Established How Are SIR Values Tested What Has Changed Things You Should Know Conclusion Q & A
Introduction Solder flux used in electronics production have been a constant evolution Since the earliest electronics assemblies rosin has been a component of electronic soldering fluxes
How Are Flux Properties Established? J-Std-004 and now J-Std-004B Updated in 2008 Manufacturer compliance is voluntary Many new products still refer to the -004A standard
Letter Designators Flux Composition RO - ROsin RE - REsin OR - ORganic IN - INorganic
Flux Residue Activity Levels
Understand the Subtle Differences Between Rosin and Resin The terms are often used interchangeably, but rosin is a naturally occurring substance, and resin is either a modified rosin or completely synthetic material. Rosins are tree products and are subject to more natural variation than resins; resins are commonly used in newer flux formulations due to their more consistent performance and tailored properties When more than one rosin/resin are combined, the IPC classification is based on the larger constituent. Therefore, if the distinction between RO and RE is important to the user, they should inquire with the flux s manufacturer to better understand the exact details of the content and classification criteria.
How Are Flux Properties Established?
How Are (S)urface (I)nsulation (R)esistance (SIR) Values Tested?
Effect of Ionic Compounds
Dendrite Formation
B-24 Coupon Corrosion ACID A ACID B ACID C ACID D ACID E
J-Std-004 v -004B What has Changed?
J-Std-004 v -004B What has Changed?
J-Std-004 v -004B What has Changed?
J-Std-004 v -004B Comparing SIR Results J-Std-004B IPC 2.6.3.7 J-Std-004 IPC 2.6.3.3
IPC Designation IPC-TM-650 method 2.3.28.1 for halide Determined halogen/halides are back calculated to the solids content of the flux
Chromatography Data for Liquid Flux
Chromatography Data for Liquid Flux Low solids fluxes are hyper sensitized by having a low solids content This causes many liquid fluxes to be classified as L1 although they are truly not
Things You Should Know
Know The Relationship Between Halides and Halogens Halides are ionic compounds typically used as activators and are often associated with corrosion. Specification of testing methods and thresholds for halide content are addressed by IPC J-Std.-004/004B Non-ionic halogenated compounds, or halogens, are the subject to REACH regulations. Specification of testing methods and thresholds for halogen content are addressed by European Environmental Standards - EN-14582. THIS IS AN ENVIRONMENTAL SPECIFICATION NOT A RELIABILITY SPECIFICATION.
Halogens in Paste Halogen vs. Halide When a halogen takes one electron, it becomes a halide Br + e Br- This causes the halogen to become a halide and is very reactive
List of Halogens (F) Fluorine (Cl) Chlorine (Br) Bromine (I) Iodine (At) Astatine
Why Halogens? These compounds are effective fluxing agents therefore less activation from organic acids is required in a flux formula Halogen compounds are thermally stable providing longer exposure time and a bigger process window They are cost effective and can be easily incorporated to flux chemistry
Halogens Are Neutral in charge non-ionic Enhance soldering when used in flux The most common use is in fire retardants for PCB laminate and in this capacity are the subject of REACH regulation
Halides Ionic, hydrophilic and can create conductive pathways Typically used in strong organic acid or inorganic acid flux Used for etching in circuit board assembly
What Classification is Your Flux Today? Fluxes older than 2008 are exempt from the new regulations and do not have to meet the specification of -004B When trying to replace them do not compare J- Std.-004 designators they are not equal. A flux classified as ORL0 under -004 is very possibly an ORL1 under -004B J-Std.-004A flux can contain much more halide as a -004B flux and still be considered halide-free.
Applying the Changes in Flux Designators to Your Process Does your flux choice suit your application process requirements This is especially critical in liquid flux Liquid flux is typically designed for wave soldering Specific fluxes should be used in consideration of the application method.
Liquid Flux Processing What About: Selective Rework Wave with palletized boards
What If Your Flux Is Not Properly Heated?
Flux Surface Insulation Resistance SIR test, the flux is heated Pre-2008 VOC free flux formulas may not pass the new SIR 2.6.3.7 Are you running a process that guarantees all liquid flux is heated? Flux deactivation is time/temperature dependent
Conclusion IPC J-STD-004B is a continually evolving specification It is important for the Engineer specifying the materials to understand the requirements for their product type IPC J-STD-004B may not always fit all assembly requirements Spacing, signal type, board materials and application methods can all affect the path of material sets specified
Questions? Q & A
Thank You Revision A