In-depth analysis of Press-Fit tech and material application

In recent years, Press-Fit technology has been increasingly used in the manufacture of electrical systems in the automotive, energy and other markets. What is Press-Fit Technology? What are the advantages of its application? What are the performance requirements for alloy materials that meet Press-Fit technology?

01

Press-Fit, also known as "fisheye termination", is an alternative solution to solder mounting. The reliable connection of electrical contacts is mainly achieved by the solder-free method of cold connection. The fisheye end is pressed into the PCB hole, and a high clamping force is obtained through a small pressing force. During the pressing process, the fisheye end is elastically deformed and provides a tight connection with low contact resistance and high reliability.

Simply put, Press-Fit creates an electromechanical interconnection without soldering, which can quickly install the connector on the PCB module. The elimination of the soldering process not only reduces the connection resistance, but also further reduces the production cost and assembly time.

02

Press-Fit technical advantages

Compared with traditional welding, PressFit has many advantages:

(1) When crimping, the PCB and components will not generate thermal stress, and the impedance is small

(2)Small insertion force, high clamping force, forming a tight connection in the contact area between the Press-Fit and the PCB

(3)It has no solder bridges, no flux residues, no cleaning, and to a certain extent avoids problems caused by soldering such as tin whiskers, cracks, and non-wetting

(4)Reusable, environmentally friendly

(5)Easy assembly, easy maintenance, simplified module replacement

03

Typical Copper Alloys for Press-Fit

Bronze: CuSn4/C511, CuSn6/C519, CuSn8/C521

Advantages: Strength level, fine grain, low Young's modulus

Disadvantages: low electrical conductivity, low stress relaxation performance under high temperature conditions (>100°C)

CuNiSi alloy: C7025, C19005/C19010

Advantages: high strength, stress relaxation performance up to 150℃/1000h, medium conductivity

Disadvantage: Higher Young's modulus - depending on loading direction

CuCrZr alloy: C18150/C18160, C18400

Advantages: high electrical conductivity, stress relaxation performance up to 175℃/1000h, medium strength

Disadvantages: forming performance, electroplating performance