The density content and hardness of tin bronze plate

Bronze can be divided into tin bronze and special bronze, code: the method of representation is "Q+ main plus element symbol and mass fraction + mass fraction of other elements". Cast products in the code before adding "Z" word, such as: Qal7 means aluminum 5%, the rest of the copper aluminum bronze ZQSN10-1 means tin content is 10%, the content of other alloy elements is 1%, the residual amount of copper cast tin bronze, by tin mainly adding elements of copper alloy, also known as tin bronze plate.

When the content of tin is less than 5~6%, tin is dissolved in copper to form a solid solution, plasticity rises, when the content of tin is greater than 5~6%, due to the occurrence of Cu31sb8 based solid solution, tensile strength decreased, so the scale of tin bronze tin content is mostly between 3~14%, when the content of tin is less than 5%, suitable for cold deformation processing, When the tin content is 5-7%, it is suitable for hot deformation processing. When the tin content is more than 10%, it is suitable for casting.

Due to the similar potential of A and & electrode, and the formation of dense tin dioxide film after nitrification in the composition, the corrosion resistance of atmosphere and sea water is increased, but the acid resistance is poor. Because of the wide crystallization temperature range of tin bronze, poor fluidity, not easy to form concentrated shrinkage, and easy to form dendrite segregation and dispersed shrinkage, casting shrinkage rate is small, is conducive to the size of the casting is very close to the cast, so it is suitable for casting complex shape. The conditions of large wall thickness are not suitable for casting castings requiring high density and good tightness.

Tin bronze has good antifriction, diamagnetism and low temperature toughness. According to the production method, it can be divided into two categories: pressure processed tin bronze and cast tin bronze. The content of tin in pressure processed tin bronze is generally less than 8%. It should be processed into plates, belts, bars, tubes and other profiles under cold and hot pressure for supply. After working and hardening, its tensile strength and hardness increase while its plasticity decreases. After reannealing, the plasticity can be improved at high tensile strength, especially the elastic limit can be obtained. Cast tin bronze is supplied by ingot and cast into castings in foundry workshops. It is suitable for casting castings with complex shapes but low density requirements, such as sliding bearings and gears.