the product: Delivering cost effective soldering performance and reliability in both Wave and Selective / Rework Soldering processes Upgrading to ALPHA Plus 0307
ALPHA Plus 0307 Introduction ALPHA Plus 0307 is the next generation of our original alloy. Plus was designed to minimise copper erosion. Copper erosion is a concern when solder contact times are long and solder temperature is high, which is common in selective soldering and rework processes. ALPHA Plus 0307 delivers the same high level of soldering performance as the original. Like the original alloy, ALPHA Plus 0307 can replace SAC 305 in most wave and selective soldering processes, at a cost well below the higher silver bearing SAC 305.
ALPHA Plus 0307 Alloy Properties * Ultra Low Lead (ULL) version, <0.05% Pb, also available *
ALPHA Plus 0307 Processing Parameters
Copper Erosion Fountain selective soldering and rework systems are normally operated at temperatures exceeding 260ºC Rework procedures can expose the copper lead and land to the molten alloy for up to 60 (or more) seconds Alloys not engineered to reduce copper erosion, particularly high silver alloys, can damage the copper land or lead making the assembly defective 15 Seconds 40 Seconds Annular ring knee with copper removed
ALPHA Plus 0307 Copper Erosion Many studies have demonstrate the low Cu erosion rates of Plus 0307 Source: inemi Cu Erosion Study, 2007 Source: Large CEM
ALPHA Plus 0307 Copper Erosion (Seconds) 35 30 25 20 15 10 5 0 Copper Erosion - Wire Break Times Increasing SAC0307 0307 Plus 0307 Time to break a fluxed 0.05mm copper wire under load of 3.6g in solder at 260C. Mean of 6 readings for each alloy. ALPHA Plus Alloys exhibit lower Cu Erosion rates than 0307 and SAC0307.
Soldering Performance Hole Fill Hole Fill is strongly correlated with the wetting performance of the alloy/flux/finish combination. Lower wetting angles are a good indicator of good soldering performance When wetting speed and force are high we should expect better hole fill -all other parameters being equal. Comparison of wetting balance test results are a strong indicator of hole fill capability.
Soldering Performance Hole Fill Plus 0307 exhibits nearly identical wetting as original 0307
Soldering Performance Number of PCI Connector holes meeting Class III (75%filled) soldering performance based on IPC-A 610C 75 Hole Fill data of Plus Alloys vs. Sn100C at 255 deg C Number of Holes 60 45 30 15 0 Sn 100C ALPHA Plus 0107 0307 ALPHA Plus 0307 ALPHA Plus 0807 SN100C and Plus TM 0807 shown as reference points that provide scale for the difference between 0307 and Plus TM 0307 Plus 0307 is a direct replacement for 0307 for most cases. For challenging boards (thicker, many copper layers) as used to generate the data above, a small increase in solder temperature may be required.
ALPHA Plus TM 0307 Dross Rate ALPHA Plus TM 0307 is manufactured using ALPHA s proprietary Vaculoy process and also contains the same levels of antioxidant as the original 0307
ALPHA Plus 0307 Reliability Thermal Fatigue Resistance ALPHA Plus TM 0307 contains the same constituents that make the original 0307 exhibit equivalent or better reliability than other leading Pb-free alloys Sampling of results from customer thermal cycling tests Test Type Lower Upper Cycles Results Thermal Cycling -40 125 2000 No difference b etween and SAC305 Thermal Cycling -40 85 1000 Lower failure rate that SAC305 Thermal Cycling -40 90 500 0 failures Thermal Shock -40 80 300 Lower failures than Sn/Cu/Ni Thermal Cycling 0 100 500 Passes requirements of PC manufacturer Thermal Cycling -40 125 1000 Equivalent to SAC305 b etter than Sn/Cu/Ni
Mechanical Reliability Tensile Test Data MPa 50 40 30 20 10 0 Tensile Test Data ALPHA Plus 0307 0307 ALPHA Plus 0107 SN100C Tensile Stress Tensile Strain Max. Displacement Yield Stress (%) Elongation Plus 0307 has similar resistance to mechanical stress than 0307 using a number of tests including Tensile Stress / Strain, Displacement and Yield.
Mechanical Reliability Pull Testing after Aging L e a d F o r c e ( g m s ) 1200 900 600 300 0 Effect of Cycling on Lead Strength on Sn 100c & Alloys Soldered at 255 deg C Sn 100C ALPHA Plus 0107 0307 ALPHA Plus 0307 ALPHA Plus 0807 0 cycles 500 cycles 1000 cycles Plus 0307 has similar pull force resistance than 0307 under various aging conditions.
Mechanical Reliability Shear Testing after Aging Shear Force (gms) 9000 7500 6000 4500 3000 1500 Effect of cycling on shear strength of chip component soldered at 265 degs C 0 cycles 500 cycles 1000 cycles 0 Sn 100C ALPHA Plus 0107 ALPHA Plus 0307 0307 ALPHA Plus 0807 Plus 0307 has similar shear force resistance than 0307 under various aging conditions.