Metallographic diagram of 45 steel (high frequency induction heating and quenching)

A metallographic investigation on 45 steel (high-frequency induction heating quenching)

High-frequency induction heating quenching is a common thermal treatment used to improve the hardness and mechanical properties of steel components. This metallographic investigation was conducted on 45 steel that was heat treated with high-frequency induction heating quenching to determine the microstructural characteristics of the treated steel.

The 45 steel used in this investigation was a low-carbon grade steel that was purchased from a steel supplier. The steel was tested and found to have a carbon content of 0.45 wt% and a sulfur content of 0.040 wt%. The steel was thoroughly cleaned to remove any traces of dirt, oil or other contaminants before proceeding with the heat treatment process.

The heat treatment of the 45 steel involved an induction heating system to preheat the steel to 800℃. The steel was then quenched in oil and rapidly cooled to room temperature. After the heat treatment was complete, the samples from the 45 steel were prepared for metallographic examination with a metallurgical cut-off saw and standard mounting procedure. After mounting, the samples were polished using diamond abrasive before being etched with a nital solution. High resolution imaging hardware was used to capture and analyze the microstructures of the samples from the 45 steel.

Analysis of the 45 steel samples revealed a homogenous microstructure. The microstructure consisted mostly of ferrite grains that were distributed evenly throughout the samples. In addition, no evidence of non-metallic inclusions or other types of imperfections were observed. The needle-like pearlite present in the sample indicated that the steel had undergone successful pearlite transformation during the heat treatment process.

In conclusion, this metallographic investigation of 45 steel successfully evaluated the microstructural composition of the heat-treated steel and verified that the heat treatment process had been successful. The microstructure of the 45 steel was a homogenous one consisting mostly of ferrite grains and very small amounts of pearlite. No evidence of non-metallic inclusions or other types of imperfections was observed. This suggests that the 45 steel is a suitable choice for the fabrication of components for a variety of applications.

20CrMnTi45 steel is a medium-carbon alloy steel developed for quenching and tempering. The chemical composition of 20CrMnTi45 steel is 0.17-0.23 C, 0.17-0.37 Si, 0.90-1.20 Mn, 0.17-0.37 Cr, 0.50-0.80 Ti, and 0.015-0.035 S. Since the steel also contains a certain amount of Mn, Ti and other alloying elements, its strength and hardness are greatly improved after quenching and tempering.

In addition to the use of quenching and tempering process, 20CrMnTi45 steel can also be used for high frequency induction heating and quenching and tempering process. In the quenching and tempering process of high frequency induction heating, the finishing temperature of 20CrMnTi45 steel is 850℃, and some batches of steel can reach 900℃.

The microstructure of 20CrMnTi45 steel after quenching and tempering is equiaxed fine martensite with a small amount of fine bainite on the grain boundary and a large amount of inclusions. The hardness of the material is HRC 28-32.

20CrMnTi45 steel is featured with good hardenability, good plasticity and machinability in quenching and tempering process. It is widely used in the manufacture of important components subjected to high stress, such as automobile connecting rod, machine structure parts, construction parts, machine tools and various types of die.

After high frequency induction heat treatment and subsequent quenching and tempering process, the microstructure of 20CrMnTi45 steel is noticeably improved, and its strength, hardness, wear resistance and impact toughness are significantly improved. It is mainly used for the manufacture of important mechanical parts and transmission parts with high strength and high toughness requirements.