Copper-Tin Segregation Tendency
Copper-tin segregation tendency is a phenomenon where tin-rich phases distribute unevenly in leaded or lead-free tin bronzes. This requires rapid cooling.
Physical-Chemical Mechanism of Action
The copper-tin segregation tendency occurs when tin-rich phases form unevenly in the cast structure during the solidification of tin bronzes. This happens due to the different solubility of copper and tin at various temperatures.
Metallurgical Relevance & Risks in Welding
If a bronze casting cools too slowly, a tin-rich phase can form unevenly, which can lead to the formation of pores and cracks. This impairs the strength and toughness of the weld.
Workshop Practice & Instructions
To avoid the copper-tin segregation tendency, rapid cooling of the cast structure is essential. This can be achieved by using cooling water or special cooling dies. The optimal cooling time should be set so that the cast structure cools within 30 seconds.