Defects Caused by Improper Heating Process
The improper heating process can lead to a variety of unsatisfactory defects in the products, including poor weld strength, poor surface geometry, poor formability and poor machinability. This paper will discuss the various defects caused by improper heating process.
Poor weld strength: Improperly heated welds may fail due to weak weld metal or insufficient joint penetration. Poor weld strength can be caused by insufficient heat input to achieve proper metal temperature, application of too much heat, inadequate preheat and inter-pass temperature, and too slow cooling rates. It is generally easier to prevent weld strength problems by controlling the welding parameters than it is to fix them after the fact.
Poor surface geometry: Improperly heated welds may have issues with undercut, porosity, and cracking. Poor surface geometry can be caused by insufficient heat, uneven heat application, too much heat, insufficient preheat, and too slow cooling rates. Excessive oxide and other surface defacements can also be caused by the improper heating process.
Poor formability: Improper heating will affect the properties of the material, making it more susceptible to deformations due to fatigue and stress. Improperly heated materials tend to have deep hardening or softening of the material, which leads to weakening of the structure. Poor formability can be caused by insufficient heat, too much heat, and too slow cooling rates.
Poor machinability: Improperly heated materials tend to have hardness variations within the material, which can lead to tools wearing faster, changes in chip size, and shorter tool life. Poor machinability can be caused by uneven heat application, insufficient preheat, and too slow cooling rates.
In conclusion, proper heating is essential in many manufacturing processes, as improper heating can lead to a variety of defects. Poor weld strength, poor surface geometry, poor formability, and poor machinability can all be caused by the improper heating process. To avoid such defects, it is important to correctly adjust the heating process, taking into account the thermal history and temperatures of the material. Doing so can help ensure the desired properties of the material are achieved, and ultimately produce high-quality end products.
