Press-Fit Technology Innovation: New Solutions with Potential
News from Research & Technology: Diehl Metal Applications is a member of the Industrial Working Group ‘Press-Fit Technology in OSP’.
Press-fit technology with flexible press-fit zones in printed circuit boards has established itself over the past decade in the area of automotive electronics, too. The major advantages of press-fit technology include extremely simple process control, the omission of temperature processes and its suitability both for miniaturization as well as for high-current applications. In Europe, immersion tin plating has primarily been used to date for printed circuit boards. Parallel to this, the more cost-effective Cu/OSP surface finish is widely used on the Asian market. To tap this cost potential for assemblies with press-fit technology, the press-fit connection for the Cu/OSP surface finish needs to be qualified.
For this purpose, the new Industrial Working Group ‘Press-Fit Technology in OSP’ has formed. Here, issues relating to the use of OSP plating for printed circuit boards are analyzed. For the three basic press-fit zone types – EoN (Eye of Needle), SpS (Spring Shape) and CrZ (Cracking Zone) – the press-fit connection was assessed according to jointly defined criteria, firstly for printed circuit board surfaces with immersion Sn plating and secondly for those with an OSP finish. Members of the Industrial Working Group include press-fit contact manufacturers and printed circuit board manufacturers (Tier 2), including Diehl Metal Applications, automotive suppliers (Tier 1) and automotive manufacturers (OEM).
The analyses conducted in the Industrial Working Group show that press-fit technology in printed circuit boards with a Cu/OSP surface finish largely achieves comparable results to printed circuit boards plated with immersion Sn. For general serial application of Cu/OSP surface finishes, additional analyses are necessary. Due to the collaboration among the various industrial partners along the value-added chain, a comprehensive, scientifically sound test program was generated and the required limit samples were made available. An independent testing laboratory allowed important insights to be gained on the OSP surface finish and its interaction with press-fit technology. These analyses have created the basis for future serial application of printed circuit boards with an OSP surface finish in combination with press-fit technology.
Further information on the test program and the results of the analyses may be found in the article <media 14894 _blank linkFile "TEXT, Artikel Einpresstechnik in Cu OSP-Oberflaechen, Artikel_Einpresstechnik_in_Cu_OSP-Oberflaechen.pdf, 1.4 MB">“Press-Fit Technology in Cu/OSP Surfaces – an Alternative with Future Potential?”</media>, published in German in PLUS 5/2015.