碳钢锻件的过热现象有哪些 Carbon steel forgings overheating phenomenon which
Carbon steel forgings forging before processing blanks need to be processed, then the process of heating in the process of overheating refers to the carbon steel forging the use of metal blanks heating temperature is too high, in the specified forging and heat treatment temperature range of residence time is too long, or due to Thermal effect caused by the temperature rise is too high caused by the phenomenon of coarse grain.
Carbon steel forgings after the overheating will appear Wei's organization. Martensitic steel after the overheating, often appear within the fabric texture, die and die steel is often a carbide angle characteristics to determine the superheat organization. Titanium alloy overheating, there is a clear β-phase grain boundary and straight and elongated Wei's organization. Alloy steel overheating after the fracture will appear stone fracture or strip fracture. Overheated tissue, due to coarse grain, will cause mechanical properties to reduce, especially the impact toughness.
The general forging plant on the overheated carbon steel forgings after normal heat treatment (normalizing, quenching), the organization can improve the performance also will be restored, this overheating is often referred to as unstable overheating; and alloy structural steel forgings serious overheating After the normal normalizing (including high temperature normalizing), annealing or quenching, the superheat tissue can not be completely eliminated, this overheating is often referred to as stable overheating.