INTRODUCTION
A No Clean mildly rosin activated solder paste designed for use in a wider
operating window range of conditions.It has exceptional longer tack time (compared to most
commercial available paste) and consistent print definition. It meets IPC, J-STD-004 &
-005 and Bellcore specifications.
AVAILABLE ALLOYS
Various low oxide spherical composed of Sn-Pb-Ag and other alloys available upon request.
Typical metal loads range from 85% - 90% for standard alloy compositions.
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Solder Powder Diameter |
| Type |
Pitch |
Mesh Size |
Microns |
Inches |
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| 1 |
STD |
-100 +/- 200 |
75-150 |
.0030 - .0059 |
| 2 |
STD |
-200 +/- 325 |
45-75 |
.0018 - .0030 |
| 3 |
Fine |
-325 +/- 500 |
25-45 |
.0010 - .0018 |
| 4 |
Ultra - Fine |
-400 +/- 635* |
20-38 |
.0008 - .0015 |
* -400 +/- 500 also available |
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STENCIL MATERIAL
Stainless Steel, Brass or Nickle Plated
SQUEEGEE
80 - 90 shore A Durometer Rubber or Stainless Steel Blade
SQUEEGEE SPEED
25 mm. to 50 mm. (1.0" to 2.0") per second for typical fine pitch printing with
89 - 268 gms/cm (0.5 lb. to 1.5 lb.) pressure.
REFLOW METHODS
Convection, IR (Infra-Red), Vapor Phase etc.
RECOMMENDED PROFILE
This profile for use with Sn63Pb37 &
Sn62Pb36Ag2 alloys and will serve as a general guideline in establishing a reflow
profile for your process. Adjustment will be necessary for use with other alloys. Various
board geometries, densities, and oven types may require further profile adjustment.
The typical reflow profile encompasses four
basic stages:
1 Preheat : 0.5 degree C to 1.0 degree C/second rate of rise
2 Soak or Dryout : 30 - 60 seconds
3 Reflow : Peak temperature should be 30 to 40 degree C above the
liquidus of the alloy for 30 to 60 seconds.
4 Cool Down: <4 degree C/second.
CLEANING
NC SM3678R is designed for No-clean applications: however, the flux residue can be
removed if necessary by using semi-aqueous system. saponified water, alcohols and other
CFC-free alternatives.
STENCIL CLEANING
This is best performed using isopropyl alcohol (IPA) as s solvent. Conventional cleaning
solvents, saponification, and other CFC-free alternatives are also effective.
SHELF LIFE, RECOMMENDED STORAGE AND
USE
6 months at 20 degree C to 21 degree C
Solder paste should be allowed to reach
ambient working temperature prior to use. Actual time reach thermal equilibrium will vary
with container size. In order to maximize the opened-jar paste performance, the paste
should be covered when not in use.
| Test |
Result |
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Test |
Result |
| J-STD-400 (IPC-TM-650) |
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J-STD-005 (IPC-TM-650) |
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| Flux Type Classification |
LO |
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Solder Paste
Viscosity |
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| Flux Induced Corrosion (Copper Mirror) |
Pass |
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(Sn63, -325/+50 mesh) |
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Presence of Halide
Silver Chromate
Fluoride Spot Test
Cl Equivalent |
Pass
Pass
<0.019% |
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Brookshield (5 rpm)
90% metal load
90.5% metal load
Malcom (10 rpm) |
850+/-100 kcps
1100+/-100 kcps |
| Non-Volatile Content (Solid Content) |
90% |
|
90% metal
load |
1600-2100 poises |
| Post Reflow Flux Residue (ICA Test) |
47% |
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Thixotropic Index : SSF (ICA Test) |
-0.57 to -0.64 |
| Corrosion |
Pass |
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Slump Test |
Pass |
| SIR |
Pass |
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Solder Ball Test |
Pass |
| Electromigration |
Pass |
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Tackiness |
38g |
| Acid Value |
85 |
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Wetting Test |
Pass |
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