A cloud of vapour enters an empty room from the right.

Vapour Phase

Avoid thermal stress in electromechanical components

Convenience, safety and access to a whole range of functionalities - this is what electromechanical components make possible. Even when used in harsh environments, switches and pushbuttons for IP applications easily meet the requirements. In collaboration with IBL-Löttechnik, Würth Elektronik eiSos
has investigated the extent to which these are also suitable for the vapor phase soldering process.

Vapour Phase Process

Boiling Process

  • Heating of the chemically inert and electrically non-conductive liquid (Galden).
  • A protective gas atmosphere is formed which prevents oxidation in the process.


Solder Process

  • The material carrier places the circuit board in the machine.
  • The vapor condenses on the soldering material until the maximum temperature is reached.

Tested Components

The WS-TASV J-Hook SMT IP67 Tact Switch is a switch measuring 6x6 mm that features a J-hook construction.

Tact Switch 6x6 mm IP67

  • Actuator length: 3.4 mm & 5.1 mm
  • Operation force: 160 gf & 250 gf
  • Working voltage: 12 VDC

430 7x3 0x x8xx

 

The WS-TASV SMT IP67 Tact Switch is a switch measuring 6.2 x 4.1 mm.

Tact Switch 6.2x4.1 mm IP67

  • Actuator length: 2.5 mm
  • Operation force: 160 gf & 260 gf
  • Working voltage: 12 VDC

434 7x1 025 8x6

The WS-DISV Small Compact SMT Flat Actuator with Top Tape and a height of 1.27 mm is a compact, flat switch.

DIP Switch SMT 1.27mm

  • Available pincounts: 1 – 12
  • Working voltage: 50 VDC

416 131 xxx xxx

The WS-DISV Small Compact SMT Flat Actuator with Top Tape and a height of 1.27 mm is a flat switch.

DIP Switch SMT 2.54mm

  • Available pincounts: 1 – 12
  • Working voltage: 50 VDC

418 121 160 xxx

The WS-ROSV SMT IP67 Rotary Switch with arrow-type actuator and dimensions of 7x7 mm is a rotary switch.

Rotary Switch 7x7 mm

  • Types: Real und Complement Code
  • Available pincounts: 10 & 16
  • Working voltage: 42 VDC

428 542 320 8xx

Structure of the test series

The first step in the test series was to measure the initial contact resistances of the various switches. A leadfree, no-clean solder paste was first applied to 160 mm x 100 mm test boards and the electromechanical components were assembled manually by Würth Elektronik.

In several batches, the test boards underwent the vapor phase soldering process in the VAC 745 vapor phase soldering system from IBL Löttechnik.

In addition to typical standard soldering profiles, the electromechanical components were also subjected to a soldering profile that reached the load limit in terms of running time and maximum temperature. Some batches were run through the vapor phase process up to five times in order to meet the maximum requirements of five reflow cycles to which a component may be exposed according to the IPC (TM-650).

Finally, Würth Elektronik comprehensively tested the components in its test laboratory with regard to the reliability of the solder joints and the electrical properties of the components.

This temperature/time profile shows the standard soldering process: Overheating of the assembly during the process is physically excluded.

This temperature/time profile shows the standard soldering process: Overheating of the assembly during the process is physically excluded.

The temperature/time profile with a significantly longer peak temperature to simulate the upper load limit

The temperature/time profile with a significantly longer peak temperature to simulate the upper load limit.

Prospect

Tests are currently underway with other components from Würth Elektronik. This page will be updated accordingly as soon as the results are known.