Metallographic study of SUS304(890℃ tempering)
Metallography is the study of the structure and composition of materials by examining them under a microscope. It is one of the most important ways for materials scientists and engineers to study the structure of a material. In this paper, an analysis of the metallographic structure of SUS304 (890℃ tempering) is presented.
SUS304 stainless steel is a grade of stainless steel with a slightly higher strength than the usual austenitic stainless steels. It has a higher percentage of chromium and nickel in its composition, resulting in increased corrosion and wear resistance. The 890℃ tempering of SUS304 stainless steel is an method by which it can be hardened and strengthened, improving its performance and helping it resist corrosion.
The metallographic structure of SUS304 stainless steel after tempering at 890℃ was studied using a metallograph. The sample was cut and polished following standard metallographic techniques. It was then etched using a mixture of ferric chloride and hydrofluoric acid, allowing the microstructure to be observed on the surface.
In general, the microstructure of SUS304 (890℃ tempering) exhibits a refined polymorphous ferritic and austenitic structure. The size and distribution of the grains is even and small, while the ferrite and austenite martensite grains are well-defined and homogeneous. The martensite grains appear as needle-like particles that are highly dispersed.
The overall grain structure of SUS304 (890℃ tempering) is relatively fine, with an average grain size of 20-30 μm and a grain boundary area of about 10%. The grain structure also appears to be stable, with no major structural changes observed in the grain size.
SUS304 (890℃ tempering) also contains a small amount of chromium carbides, which appear as small dark patches on the surface of the sample. These carbides provide an important protection against corrosion.
The results of the metallographic study show that SUS304 (890℃ tempering) is a highly homogeneous steel with a fine grain structure and a stable structure. It also provides good protection against corrosion due to the presence of chromium carbides.
Overall, SUS304 (890℃ tempering) is a good quality stainless steel with excellent mechanical and corrosion resistance properties. It is suitable for many applications such as chemical, aerospace, and other industries where high performance and corrosion resistance is necessary. It is also cost effective, making it a popular choice among many manufacturers.
