Eutectoid Decomposition Product
Eutectoid decomposition product is a phase mixture of ferrite and cementite that forms at the critical temperature. It has a lamellar structure and influences the mechanical properties of the steel.
Physical-Chemical Mechanism of Action
When cooling high-temperature steels, a phase mixture of ferrite and cementite forms at the critical temperature. This mixture forms a lamellar structure composed of various layers of ferrite and cementite.
Metallurgical Relevance & Risks in Welding
The eutectoid decomposition product influences the mechanical properties of the steel, such as hardness and elasticity. Too many lamellae can reduce toughness and promote cracking. It is important to control cooling to achieve a homogeneous structure.
Workshop Practice & Action Instructions
To avoid or minimize the eutectoid decomposition product, the steel should be cooled in a controlled temperature range during welding. This can be achieved by choosing the right welding process and correct cooling time. For high-temperature steels, it is especially important to cool slowly and uniformly.