Introduction
Forging is an important metalworking process that involves forming and reshaping the metal by applying force. Metal forging is an integral part of many industries including automotive, aerospace, shipbuilding, and engineering. The metal forging process involves heating the metal to the desired temperature, forming it according to the shape that is desired, and then cooling and finishing it. During the process, a variety of defects can occur both in the metal and in the forging itself. This paper will discuss the main defects of raw materials used in metal forging and the defects in the forgings caused by them.
Defects of Raw Materials Used in Forging
The primary defects of raw materials used in forging can be divided into two categories: surface-level defects and subsurface-level defects.
Surface-level defects of raw materials used in forging are usually caused by corrosion or inadequate surface preparation. These defects can usually be easily seen and can include cracking, scaling, pitting, and corrosion.
Subsurface-level defects are internal defects and occur when the material has not undergone proper heat treatment. These defects can include porosity, inclusions, voids, and microcracks.
Defects in Forgings Caused by Raw Materials
The defects in forgings caused by raw materials can also be divided into two categories: surface-level defects and subsurface-level defects.
Surface-level defects are visible to the eye and can include cracking, scaling, and pitting. These surface-level defects can be caused by the raw material’s surface not being properly prepared or poor selection of material properties such as grain size, size distribution, and chemistry.
Subsurface-level defects are internal defects and can include material segregation, cavity shrinkage, and decarburization. Subsurface defects are caused by a variety of factors including inadequate heat treatment, improper control of forging temperatures, and variations in material properties.
Conclusion
Metal forging is an important process used in many industries. In order to ensure that the process produces forgings of the highest quality, it is important to understand the main defects of raw materials used as well as the defects in forgings caused by them. In general, the defects of raw materials used in forging can be divided into surface-level and subsurface-level defects, and the defects in forgings can also be divided into surface-level and subsurface-level defects. Proper material selection, preparation, and heat treatment can help prevent defects and help ensure the highest quality end product.
