Performance characteristics of high lead bronze
With the development of large-scale machinery and equipment, the requirements for important parts have become more stringent. Bearings and bearing bushes are important wear-resistant parts of large-scale equipment such as metallurgy, electric power, and mining. During production work, they not only withstand greater pressure, impact loads, and alternating stresses, but also withstand friction, wear, higher temperatures, and a variety of The corrosive effect of the medium on it. Ordinary tin-based and lead-based Babbitt alloy and cast iron-based bearing materials can no longer meet the requirements. High-lead bronze alloy has excellent dry friction properties, high thermal conductivity, fatigue resistance and seizure resistance, and is currently widely used.
High lead bronze is a very versatile alloy material. However, because the melting points and specific gravity of copper and lead are very different, lead segregation is easily produced.
High-lead bronze has excellent qualities such as high fatigue strength, thermal conductivity and wear resistance, as well as no cracking under working conditions with impact loads.
High-lead bronze bearing bushes and copper-lead alloy bearing bushes mainly produced by the centrifugal casting method. Due to the high preheating temperature of the steel shell and the high temperature of alloy casting, a rapid cooling method must be used to prevent lead segregation during the casting process. Therefore, the back surface of the steel gets a "quenching effect", which increases the hardness and reduces the toughness. Not only will it bring difficulties to future cutting processes, but also due to the large internal stress of the bearing after casting, the shape and size of the bearing will change during the processing, and the accuracy will be affected to a certain extent. What's more serious is that the increase in hardness and decrease in toughness of the steel back caused by the "quenching effect" is one of the important reasons for the bearing to break or even chip during use.
