With the development of artificial intelligence and vehicle networking technology, the future direction of automobile development is towards human-computer interaction with a longer time, deeper level and higher frequency. In order to meet these characteristics to give passengers the ultimate driving experience, the choice of basic materials is particularly important.
Future Intelligent Vehicle Market
In the future, the size of the intelligent vehicle market is forecast to grow at a CAGR of 20.62%, and the domestic market is expected to reach more than 200 billion CNY by 2023. In the transition from traditional cars to smart cars, the connector market will also increase at a high rate because of the increase in intelligence and functional components.
Throughout history, the automobile industry has experienced the steam age, the mechanical age, and the electronic age. They are corresponding to the stage of no automation, driving system assistance, partial automation and conditional automation, and then to the stage of L4 high automation which is currently under development.
The global autopilot penetration rate will increase rapidly according to the IHS forecast. From the forecast below, by 2040, all new cars will be equipped with autopilot function, of which the L4/L5 class autopilot penetration rate will be up to 50%.
New challenges for connectors
Compared with traditional cars, smart cars will add a large number of components such as cameras, radar (laser, millimeter wave, ultrasonic), sensors, positioning navigation, network communication (multi-sensor) and other components. These components are used in systems such as intelligent sensing, auxiliary driving, intelligent computing, intelligent public transport, audio and video entertainment, etc.
Connectors connect these components to the system, which are very important links in the entire system and can greatly aﬀect the operation of these functional components.
In intelligent driving without artificial intervention, the high-speed transmission performance and stability of connectors are the decisive factors for the safe operation of intelligent vehicles. Meanwhile, due to the multiplication of components, the miniaturization of connectors has become another inevitable trend.
The development of automobile intelligence means a sharp increase in data transmission. The components for high-speed network connection, high-definition entertainment system, automatic driving auxiliary system with high resolution and high precision sensor and radar greatly increase the number of high-speed data nodes. Under different application environments, such as vehicle network, entertainment systems, GPS antennas, ADAS, radar and so on, the transmission rate of the product will be from 1 Gbps up to 12 Gbps and above. For products with diﬀ e-rent rates, the conductivity of copper will be diﬀerent. The higher the transmission rate of the product requires the higher the electrical conductivity of copper.
Safety is about life. Under the condition of high-speed transmission, it is a major challenge for the industry to ensure the security and reliability of data transmission.
The automotive industry has very high requirements for connectors, which need to be suitable for harsh and complex environments while meeting the needs of long-term operation. This series of requirements is translated into connector retention, chemical resistance, temperature resistance mechanical impact, mating force and temperature cycle indicators. For electrical, mechanical and environmental characteristics of connector products have high requirements as well. Therefore, in the selection of copper alloy materials, we should pay attention to the stress relaxation, yield strength and high temperature resistance of the materials.
In addition to high-speed transmission and security reliability, miniaturization is also a major requirement. Reducing the size of the connector but remaining the same mechanical and electrical characteristics will be challenging. For example, how to ensure the terminal con-tact impedance, current conduction rate, retention force, electromagnetic interference resistance? Under these conditions, higher requirements are put forward for the strength, conductivity and stress relaxation of copper. For example, if bronze conductivity can still meet the requirement after miniaturization? Whether the material strength can still keep up after miniaturization?
KMD material solutions
The high-speed transmission of connectors is highly related to the properties of raw materials. Higher conductivity of the material can support a greater transmission rate of the products. In the meantime, it has a certain elasticity to help reduce the contact impedance. Such as Fakra and HSD connectors, diﬀerent transmission rate will need different material. For example, pin needles will use brass or bronze, shrapnel will use phosphorus copper or copper-nickel silicon. According to the demand of diﬀerent mate-rials, KMD can provide a complete copper strips solutions. Safety and reliability are the top priority of products. From passive safety, active safety to functional safety is the problem that automobile manufacturers should solve at all costs when developing and designing.
Good stress relaxation and yield strength of the material can ensure the long-term eﬀective connection of the system. And good electrical conductivity of the material ensures the eﬀective control of temperature rise under high temperature working conditions.
KMD CuNiSi series alloys have high strength, good electrical conductivity and excellent stress relaxation performance. Its application fish-eye terminals can be widely used in automotive module connectors and electronic control units. Fish-eye terminals made by CuNiSi alloys have good adhesion and retention, greatly improving the stability and safety of the system.
The miniaturization of the product can improve the integration of the system. However, the miniaturization of connectors will cause a decrease in copper thickness, which will reduce the conductivity of the product and the forward force. Therefore, higher strength, higher conductivity materials are needed in this circumstance. Miniaturized wire harness connectors support data transmission rates up to 100 Mbps, and KMD’s mass-produced high-elastic bronze products are very suitable for use in such products.
In addition, tin coating is also an excellent solution for smart car connector applications. For example, the tin-silver coating on the automobile terminals can provide higher conductivity, higher positive force and good solderability than traditional tin coating.
Besides tin-silver coating, KMD can also provide pure tin and thermic tin coating. KMD Group has inherited Germany's traditional technology and mature experience in hot-dip tinning. Hot-dip tin has excellent properties such as reducing mating force, improving welding ability between copper substrates, corrosion and oxidation protection, and whisker free. HDT can help customers in various working conditions of products to provide diﬀerent solutions. KMD Group helps customers choose the right copper alloy solution in order to stand out in the competitive automotive electronics industry.