Several typical examples of post-weld heat treatment

Normalizing: Usually performed on carbon steel to provide a stress-free fine grain structure. This is achieved by making the temperature higher than the temperature at which most materials undergo a phase change (usually around 950°C) and then cooling it in still air. By performing this treatment on ordinary carbon/carbon-manganese steel, they will develop a good balance of strength and toughness. This is a very typical heat treatment applied to steel castings, forgings and other steels to achieve fine grain structure.

Precipitation hardening: If the temperature of certain materials is increased and maintained for a period of time, very small particles will form in their structure. These small particles are called sediments. The presence of these small particles acts as a reinforcing material. A typical precipitation hardening cycle is as follows: Set the temperature of the material to the point where the "solution treatment" will be performed. The material is then "quenched" to ensure that no precipitate forms. Next, the temperature is raised again (but lowered to a temperature below the temperature of the solution), and then precipitates are induced to form. This is called "aging" treatment. It is important to note that if the temperature is too high, or if it rises for too long during this part of the cycle, the material will "age". Compared with properly aged materials, overly aged materials will have lower hardness and strength. Similarly, if the aging temperature or time is too low, the material will "age", which in turn leads to a decrease in hardness and strength. Aging is not a problem, because you can increase the temperature again to further aging until the best results are obtained. Excessive aging is a bigger problem, because it can only be solved by executing the entire cycle again. (From solution treatment.) Because you can increase the temperature again to further aging until you get the best results. Excessive aging is a bigger problem, because it can only be solved by executing the entire cycle again. (From solution treatment.) Because you can increase the temperature again to further aging until you get the best results. Excessive aging is a bigger problem, because it can only be solved by executing the entire cycle again. (From solution treatment.)

Thermomechanical Control Process: (TMCP) Strictly speaking, this is not heat treatment, but I think this is a good place for a brief discussion. In TMCP, the steel is deformed (for example, rolled), while the temperature is not high enough to cause total phase transformation and recrystallization, but the temperature is not low enough to cause only cold forming. Each steel mill often has its own temperature and deformation sequence to obtain a strong material that is easy to weld. TMCP steel tends to have a low carbon equivalent while still being very hard.