To be clear from the outset, this topic is purely theoretical. The facts listed here are achievable if work is carried out in a perfect production environment, with pre-products without tolerances etc. This does not correspond to reality. In fact, this does not correspond to reality. In all process variants of assembly and connection technology, the final soldering quality is dependent on optimum layout geometries of the assemblies, pin-pad component geometries and wetting-friendly metallisation of all components involved. Added to this are the associated fluxes and soldering materials as well as the holistic soldering automation concept.
Nevertheless, we look at this question of which soldering process delivers the best qualitative results from a purely technical perspective. The following soldering process comparisons are based on a basic physical quality weighting as an initial orientation. The process capability index Cpk or the parts per million (ppm) values are initially to be evaluated independently and therefore neutrally by the manufacturer of the soldering automation. However, the actual ppm tolerance range is very much dependent on the core competence and professionalism of the soldering automation manufacturer.
With this approach, all selective soldering processes can be evaluated in relation to each other and placed in an overall economic context with the additional boundary conditions. For a project foresighted quality assessment, a Process evaluation under real process conditions is essential. This approach makes it possible to make the planned investment decision with full certainty.
Due to the fundamentally physically robust process factors, the mini-wave soldering process in its professional realisation represents the first choice of possible selective soldering processes in terms of quality.
- 0.3 as Cpk value corresponds to 32% corresponds to 320,000 ppm
- 1.00 as Cpk value corresponds to 2.7% corresponds to 2,700 ppm
- 1.33 as Cpk value corresponds to 0.0063% corresponds to 63 ppm
- Mini wave soldering process under inert gas: 0.01 to 0.05 %: 100 to 500 ppm
- Laser soldering process0.1 to 3 % = 1,000 to 30,000 ppm
- Piston soldering process0.9 to 7 % = 9,000 to 70,000 ppm
- Thermode soldering process0.3 to 3 % = 3,000 to 30,000 ppm
- Induction soldering process0.3 to 3 % = 3,000 to 30,000 ppm
- Reflow soldering process: 0.005 to 0.030 %: 50 to 300 ppm
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