Heat Treatment Specification of the Newly Developed Substrate Steels in China
From the global perspective, China has developed a number of new and innovative technologies in the field of steelmaking, particularly in the area of substrate steels. In order to ensure that these steels properly perform in applications, the corresponding heat treatment requirements have to be met. This article will formulate the heat treatment specification for the newly developed substrate steels in China.
Firstly, the substrate steels must be heated to an appropriate temperature for heat processing. When heated, the heating temperature should be no lower than the tempering temperature of the given steel and no higher than the normalizing temperature. Generally speaking, the heating temperature should be 800 to 1000 degrees Celsius. The temperature should be watched and controlled strictly during the heating process.
Secondly, the duration of the heat treatment methodology should be decided according to the actual situation. Generally, the duration of conventional heat processing should be in the order of 10 to 20 minutes. If a special heat treat or alloy is required, then the duration should be extended to a higher order 0f 20 to 30 minutes.
Thirdly, the quenching temperature range should be between 800 to 1000 degree Celsius for normal alloy steels. If a so-called superheat is necessary, then the temperature range should be 1300 to 1500 degree Celsius.
Fourthly, the quenching rate should be kept to an appropriate level. In general, the quenching rate should not exceed 0.5 degree Celsius per second to facilitate effective heat processing. All quenching operations must be performed rapidly and evenly to ensure the performance and functionality of the final product.
Fifthly, the tempering temperature should be determined according to the required strength of the final substrates. Generally, the tempering temperature should range between 150 to 650 degree Celsius, with the lower temperature being preferred for higher strength steels.
Finally, the annealing temperature should be determined based on the type of substrate steel. Generally speaking, the annealing temperature should be between 200-700 degrees Celsius with the lower temperature being applied to materials with higher strength.
In conclusion, the above heat treatment specification must be strictly followed by the heat treaters of newly developed substrate steels in China. The proper implementation of the heat treatment process is the key to maximizing the efficiency and the performance of the steels.
