Thermal Expansion Coefficient in Welding
The thermal expansion coefficient indicates how the volume of a metal changes when heated or cooled. It is important for calculating stresses and distortion in weld zones.
Physical-Chemical Mechanism of Action
The coefficient of thermal expansion (α) describes how a material's volume changes with temperature. It is given in 1/Kelvin and indicates the percentage change in length or volume per Kelvin increase.
Metallurgical Relevance & Risks in Welding
Welding can cause large temperature differences, leading to thermal stresses. These can deform the material or cause cracking if too high. The expansion coefficient helps predict and avoid these stresses.
Workshop Practice & Instructions
To minimize thermal stresses, design the welding process for even heating and cooling. This can be done by choosing the right process and controlling temperatures. For metals with high expansion coefficients, especially, ensure continuous cooling to avoid thermal stresses.