|
SOLDERING
The soldering tests are conducted to determine if materials
can withstand soldering effects, such as resistance to soldering heat,
as well as the solderability of components during the manufacturing process.
RESISTANCE TO SOLDERING HEAT
The test is performed for the purpose of determining whether component
parts can withstand the effects of the heat to which they will be subjected
during the soldering of their terminations. The heat can be either conducted
heat through the termination into the component part, or radiant heat
emanating from the solder dip or soldering iron when in close proximity
to the body of the component part, or both. The heat of soldering can
affect the electrical characteristics and cause mechanical damage as well
to the part: Electrical characteristics of resistive elements, semiconductor
devices, soldered connections, and insulation materials are affected in
varying degrees by heat. Mechanical damage, such as loosening of terminations
of windings, softening of insulation, opening of solder seals, and weakening
of mechanical joints, can occur.
Resistance to soldering heat testing is specified in
the following:
MIL-T-27,
MIL-STD-202, MIL-STD-750, MIL-S-3928, MIL-S-8805, MIL-C-11015, MIL-F-15733,
MIL-F-18327
SOLDERABILITY
The purpose of this test is to determine the solderability of solid and
stranded wires up to 1/8 inch thickness, as well as lugs, tabs, hook leads,
turrets, etc., which are normally joined by a soldering operation. This
determination is made on the basis of the ability of these terminations
to be wetted by a new coating of solder, or to form a suitable fillet
when dip soldered to a specially prepared solderable wire. An accelerated
aging test is included in this method which simulates a period of natural
aging under a combination of various storage conditions. This test, simulates
the effect of the environment on materials prior to soldering.
Solderability testing is specified in the following:
MIL-PRF-27,
MIL-T-27, MIL-STD-202, MIL-STD-454, MIL-STD-750, MIL-STD-3885, MIL-S-3928,
MIL-S-15743, MIL-S-10399, MIL-C-11015, MIL-I-11683, MIL-R-13312, MIL-F-13926,
MIL-C-14550, MIL-W-16878, MIL-T-17301, MIL-F-18327, MIL-R-18546, MIL-M-19097,
MIL-H-19760, MIL-N-19900, MIL-S-20708, MIL-T-21200, MIL-S-22432, MIL-L-23886,
UL-471,
UL-42
|