Do you know the six delivery status of steel-Part 2
4. Annealing state
The steel is annealed and heat-treated before leaving the factory. This delivery state is called the annealed state. The purpose of annealing is mainly to eliminate and improve the structural defects and internal stress left over from the previous process, and to prepare for the organization and performance of the subsequent process, alloy structural steel, structural steel to ensure hardenability, cold heading steel, bearings Steel, tool steel, steel for turbine blades, and steel wire-type stainless heat-resistant steel are usually delivered in an annealed state.
5. High temperature tempering state
The steel is subjected to high temperature tempering heat treatment before leaving the factory. This delivery state is called high temperature tempering state. The high tempering temperature of high temperature tempering is beneficial to completely eliminate internal stress and improve plasticity and toughness. Carbon structure, alloy steel, and structural steel with guaranteed hardenability can be delivered in high temperature tempering state. Some martensitic high-strength stainless steels, high-speed tool steels and high-strength alloy steels, due to their high hardenability and the strengthening effect of alloying elements, are often subjected to a high temperature tempering after quenching (or tempering) to Medium carbides are properly aggregated to obtain coarser tempered sorbite structure of carbide particles (similar to the spheroidizing annealing structure). Therefore, the steel in this delivery state has good cutting performance.
6. Solution treatment state
The steel is solution treated before leaving the factory. This delivery state is called the solution treatment state. This state is mainly applicable to the treatment of austenitic stainless steel before delivery. Through solution treatment, a single-phase austenite structure is obtained to improve the toughness and plasticity of the steel, create conditions for further cold working (cold rolling or cold drawing), and also prepare the structure for further precipitation hardening.