Tin trace element detrimental effect
Tin trace elements lead to segregation at grain boundaries and promote temper embrittlement, which causes porosity and reduced strength.
Physical-Chemical Mechanism of Action
Tin trace elements react with other metals in the weld pool and concentrate at grain boundaries. This enrichment can impair the crystal structure by hindering the growth of new grains.
Metallurgical Relevance & Risks in Welding
The concentration of tin at grain boundaries promotes temper embrittlement. This leads to porosity in the weld, which reduces the strength and mechanical properties of the material. Additionally, it can cause hot cracking and other quality issues.
Workshop Practice & Instructions
To minimize the negative effect of tin trace elements, keep the content in the weld pool at minimal levels. For high-tin alloys, careful control of melting processes is essential. Avoid rapid cooling and ensure the weld has enough time to cool and stabilize the structure.