The Best Material For Socket Shrapnel
Which is the best material for socket shrapnel, pure copper or Tin Phosphorus Bronze?
People who have a little knowledge of the switch socket know that the material is the most important to judge the quality of a socket, especially the shrapnel material directly related to the socket performance. The author mentioned in the previous article "how to identify the quality of switch socket: contacts and shrapnel". The best copper material of socket is copper.
However, some careful friends found that many famous brand sockets now use Tin Phosphorus Bronze shrapnel and claim to be superior to pure copper. Is this the case? Which is better, pure copper or Tin Phosphorus Bronze?
1、 Socket spring performance requirements
The spring piece of socket mainly plays the role of clamping the plug and realizing the conductivity, which requires the spring piece to have excellent conductivity first, and the second is to have good elasticity and flexibility. The strength of the combination of spring piece and plug is not small, which can not only clamp the plug, but also pull it out easily. The spring back of spring piece is good. After repeatedly pulling and inserting, its elasticity and spring back attenuation should be within the control range, The national standard is to be able to experience 40000 times of repeated plug-in. At the same time, the shrapnel should not rust, resist oxidation and arc, otherwise it will lead to the decline of conductivity.
2、 Performance comparison between pure copper shrapnel and Tin Phosphorus Bronze shrapnel
Before the advent of composite materials, pure copper was indeed the best conductive material, and the performance of copper materials also had high and low points. Specifically, the purer the copper, the better the conductivity. Copper is better than brass, but copper has its inherent defects, one is soft, the second is low toughness, rebound performance is not particularly excellent, in addition, it is easy to oxidize and rust. Of course, compared with the current popular Tin Phosphorus Bronze, these properties of Tin Phosphorus Bronze are better than pure copper, especially the remarkable improvement of oxidation resistance, hardness and toughness. Generally, the shrapnel made of Tin Phosphorus Bronze can be easily pulled and inserted more than 50000 times, some of which have good performance can even be doubled, the number of times of repeatedly unplugging and inserting is more than 80000, so it's not surprising that some switch socket brands can call out 20-year warranty and lifetime warranty.
In a word, the socket shrapnel is an important element directly related to the performance of the socket. We cannot ignore the inspection when purchasing. In addition to paying attention to the shrapnel material, we also need to check the thickness and workmanship of the shrapnel, whether it is riveted or integrally formed, which are also related to the performance and life of the socket.