45 steel heat treatment

       Quenching and tempering has a range of hardness, generally between 225-297HB. 45# steel is quenched and tempered, that is, quenching + high temperature tempering, the hardness should be at 297HB, that is, 31 ~ 32HRC! This is the most ideal state. This value may not be reached in general.

       45 steel quenching, if water quenching can generally reach 40----60HRC (according to water temperature and material size), quenching with oil is generally between 30----55HRC (depending on the thickness of the material and the type of quenching oil) ).
       There is no relationship between cracking and cracking and how much hardness is reached during the heat treatment, which is related to the shape of the workpiece and the heat treatment method.

       Medium and low carbon steels generally use normalizing. After the normalizing, the pearlite structure is obtained, which is convenient for cutting. High carbon steel, alloy steel is annealed (normal, spheroidized, isothermal.)

       Quenching and tempering is a double heat treatment of quenching and high temperature tempering, the purpose of which is to make the workpiece have good comprehensive mechanical properties.

       Quenched and tempered steel has two types of carbon quenched and tempered steel and alloy quenched and tempered steel. Whether it is carbon steel or alloy steel, its carbon content control is strict. If the carbon content is too high, the strength of the workpiece after quenching and tempering is high, but the toughness is not enough. If the carbon content is too low, the toughness is increased and the strength is insufficient. In order to obtain good overall performance of the tempering parts, the carbon content is generally controlled at 0.30~0.50%.

       During quenching and quenching, the entire section of the workpiece is required to be hardened, so that the workpiece is obtained by fine-stacked quenched martensite. By tempering at a high temperature, a microstructure mainly composed of uniform tempered sorbite is obtained. It is impossible for a small factory to conduct metallographic analysis for each furnace. Generally, it is only used for hardness testing. That is to say, the hardness after quenching must reach the quenching hardness of the material, and the hardness after tempering is checked according to the requirements of the drawing.
The operation of the workpiece quenching and tempering must be carried out strictly according to the process documentation. We only give some thoughts on how to implement the process during the operation.https://www.supplyforever.com/