Preliminary Treatment of 65Si2MnWA Steel
Thermal treatment, also known as heat treatment, is a process involving physical change of a material subjected to an appropriate combination of temperature, time and cooling. 65Si2MnWA steel is a medium-carbon steel alloy containing an elemental composition of 0.65 percent silicon, 2 percent manganese, 0.12 percent sulfur, 0.02 percent phosphorus, and 0.12 percent vanadium. As such, the physical and chemical properties of the material are vastly different from that of the parent alloy.
The thermal treatment conducted on 65Si2MnWA steel consists of two stages. The first stage involved heating the material up to 1100°C for 20 minutes. The second stage of the thermal treatment process was the hardening step – a quick cooling process which quenches the material with cold water. This process involved heating the material to 475°C and then quenching it with cold water for 5 seconds.
The purpose of the thermal treatment process is to optimize the mechanical and physical properties of 65Si2MnWA steel. After undergoing thermal treatment, soft and malleable 65Si2MnWA steel becomes much harder and more resilient. Its ductility and toughness is also greatly improved.
Before performing the thermal treatment process, it is important to analyze the original condition of the 65Si2MnWA steel and assess the microstructure. From the microscopic observation, it is possible to determine the orientation and type of grain of the material. It is also important to ensure that the proper heat treatment was done on the material to remove any internal and surface stresses that may have been previously present.
The heat treatment of 65Si2MnWA steel requires both a furnace with precise temperature and time control, as well as a supplementary chiller. The temperature of the furnace needs to be adjusted in order to sustain the 1100°C range that was desired for the first stage of the treatment. The chiller is then used to quench the material after it is heated up to 475°C in order to complete the second stage of the treatment.
To further understand the changes that have occurred after the thermal treatment, a directional metallographic analysis was required to be conducted. To do this, some cross sections of the material were cut and then polished to obtain a clean surface. After that, they were etched with nital or aqua regia solution and observed under a microscope. This revealed the changes in the microstructure of the material as a response to the two stages of heat treatment.
The metallographic observations revealed that the grains were well-aligned after the heat treatment and their shape was smooth. It was also found that no impurities were present in the material, confirming that the material had gone through a successful thermal treatment. The process was also confirmed to be effective in optimizing the physical properties of the 65Si2MnWA steel.
Thus, the thermal treatment of 65Si2MnWA steel was successful in achieving the desired outcome. The microstructure shows that the grains of the material were well-aligned after the heat treatment and the material was also found to have no impurities. Furthermore, the process was observed to be effective in optimizing the physical properties of 65Si2MnWA steel, making it much harder and more resilient.
