ACS R&D : Press-Fit Technology and Tin Whiskers

As a specialist in industrial connectivity, ACS continuously improves its technical solutions to ensure a high level of reliability.

In this context, the company has been collaborating for several years with the Science and Engineering of Materials and Processes laboratory (SIMaP) at Université Grenoble Alpes. This partnership led to a CIFRE PhD focused on the study of whisker growth in solderless interconnection processes, particularly for press-fit connectors used on printed circuit boards (PCBs).

This work contributes to enhancing product reliability while optimizing manufacturing processes.

Press-Fit Technology: A Reliable Solution for Printed Circuit Boards

Press-fit technology is an assembly method used to integrate connectors onto printed circuit boards without soldering.

Operating Principle

The process consists of inserting a metallic contact into a plated through-hole of the PCB. During insertion, the contact undergoes controlled deformation and exerts mechanical pressure on the hole walls, ensuring both a durable electrical and mechanical connection.

Advantages of Press-Fit

This technology offers several key benefits for industrial and automotive applications:

elimination of soldering operations
high mechanical retention strength
reduced environmental impact (RoHS compliance)
simplified assembly processes

These advantages explain its growing adoption in demanding environments.

Tin Whiskers: A Major Reliability Concern

Tin-based coatings are widely used in electronic systems for electrical contacts.

Whisker Formation

Over time, these coatings may generate whiskers—thin, hair-like tin filaments that can reach several millimeters in length.

They typically form on thin layers deposited on copper alloy substrates, commonly used in press-fit connectors.

Associated Risks

Whiskers pose a significant reliability risk, as they can lead to:

short circuits
intermittent failures
overall degradation of system reliability

A CIFRE PhD Supporting Industrial Performance

The PhD conducted with the SIMaP laboratory aims to better understand whisker formation mechanisms and influencing parameters.

This research contributes to:

improving metallic coatings
reducing whisker formation
enhancing connector reliability

Through this collaboration between academia and industry, ACS develops increasingly robust press-fit solutions tailored to the most demanding applications.