Availability, Printing parameters, Recommended reflow profile – HMC Electronics EM828 Kester Lead-Free Solder Paste User Manual
Page 2: Cleaning, Storage, handling, and shelf life, Health & safety

Application Notes
Availability:
Kester EM828 is available in the Sn96.5Ag3.0Cu0.5 alloy with Type 3 and Type 4 powder. Type 3 powder
mesh is recommended, but Type 4 powder is available for finer pitch applications. For specific packaging
information see Kester's Solder Paste Packaging Chart for available sizes. The appropriate combination
depends on process variables and the specific application.
Printing Parameters:
Squeegee Blade
80 to 90 durometer polyurethane or stainless steel
Squeegee Speed
Capable to a maximum speed of 150 mm/sec (6 in/sec)
Stencil Material
Stainless Steel, Molybdenum, Nickel Plated, Brass
Temperature/Humidity
Optimal ranges are 21-25°C (70-77°F) and 35-65% RH
Recommended Reflow Profile:
The recommended reflow profile for EM828 made
with SAC alloys is shown here. This profile is
simply a guideline. Since EM828 is a highly
active solderpaste, it can solder effectively over a
wide range of profiles. Your optimal profile may be
different from the one shown based on you oven,
board and mix of defects. Please contact Kester if
you need additional profiling advice.
Cleaning:
EM828 residues are best removed using automated cleaning equipment (in-line or batch) within 48 hours of
soldering. De-ionized water is recommended for the final rinse. Water temperatures should be 49-60°C
(120-140°F). Kester's 5768 Bio-Kleen
®
saponifier can also be used in a 1-2% ratio for aqueous cleaning
systems.
Storage, Handling, and Shelf Life:
Refrigeration is the recommended optimum storage condition for solder paste to maintain consistent viscosity,
reflow characteristics, and overall performance. EM828 should be stabilized at room temperature prior to
printing. EM828 should be kept at standard refrigeration temperatures, 0-10°C (32-50°F). Please contact
Kester if you require additional advice with regard to storage and handling of this material. Shelf life is 6
months from date of manufacture and held at 0-10°C (32-50°F).
Health & Safety:
This product, during handling or use, may be hazardous to health or the environment. Read the Material
Safety Data Sheet and warning label before using this product.
World Headquarters: 800 West Thorndale Avenue, Itasca, Illinois, 60143 USA
Phone: (+1) 630-616-4000 • Email: [email protected] • Website: www.kester.com
Kester Reflow Profile
SnAgCu Alloys
0
50
100
150
200
250
300
0
30
60
90
120
150
180
210
240
270
300
Time (sec.)
Temperature (C)
Pre-heating Zone
(2.0-4.0 min. max.)
Soaking Zone
(2.0 min.max.)
60-90 sec. typical
Reflow Zone
time above 217 C
(90 sec max)
60-75 sec. typical
Peak Temp.
235 - 255 C
<2.5 C/Sec
Asia Pacific Headquarters
500 Chai Chee Lane
Singapore 469024
(+65) 6449-1133
European Headquarters
Zum Plom 5
08541 Neuensalz
Germany
(+49) 3741 4233-0
Japanese Headquarters
20-11 Yokokawa 2-Chome
Sumida-Ku
Tokyo 130-0003 Japan
(+81) 3-3624-5351
The data recommendations presented are based on tests, which we consider reliable. Because Kester has no control over the conditions of use, we disclaim any responsibility connected with the
use of any of our products or the information presented. We advise that all chemical products be used only by or under the direction of technically qualified personnel who are aware of the
potential hazards involved and the necessity for reasonable care in their handling. The technical information contained herein is consistent with the properties of this material but should not be used
in the preparation of specifications as it is intended for reference only. For assistance in preparing specifications, please contact your local Kester office for details.
EM828
Rev: 21Sep09
Documentation Provided By HMC Electronics
33 Springdale Ave. Canton, MA 02021
(800) 482-4440