Lattice Parameter Mismatch
Lattice constant mismatch is the difference in lattice spacing between different crystal phases. It affects elastic strain energy and thermal stability.
Physicochemical Mechanism of Action
The lattice constant is the distance between atoms in a crystal lattice. During phase transitions or when joining different materials, these distances can differ, leading to lattice constant mismatch. This mismatch can increase elastic strain energy and impair thermal stability.
Metallurgical Relevance & Risks in Welding
High lattice constant mismatch can lead to stress development, which can cause cracks or distortion during cooling. This is especially dangerous in highly stressed components or at high temperatures.
Workshop Practice & Action Guidelines
To minimize lattice constant mismatch, choose materials with similar crystal structures and avoid strongly different phases. When welding, ensure controlled cooling to reduce stresses. If needed, use special welding methods like gas welding or electrolytic welding that cause less mismatch stresses.