It is also important to choose the quenching temperature of the steel bar quenching and tempering treatment line

Ортоңку жыштык дарстарында жана жылытуу жабдууларынан often uses scanning quenching when the heating area of the workpiece is large and the power supply is small. At this time, the calculated heating area A refers to the area encompassed by the inductor. With the same power density, the required power source is small, and the equipment investment cost is low, which is suitable for small batch production.

The steel bar quenching and tempering heat treatment equipment has a certain quenching heating temperature range for each steel grade. Only by heating and quenching within this temperature range can satisfactory structure and performance be obtained. When the heating rate is constant, if the selected quenching temperature is lower than the optimal temperature, because the phase transformation is not complete, the hot structure is austenite plus ferrite, or austenite plus spherite, the quenched The structure is martensite plus ferrite or martensite plus pearlite, and the hardness will decrease. If the quenching heating temperature is higher than the optimal temperature, the hot austenite grains will grow, and the result will be obtained after quenching. Middle needle or thick needle martensite, if it is high carbon steel, there will be retained austenite, which will reduce the surface hardness.

In actual production, if the optimal quenching temperature range of a certain steel grade is determined, but because the heating rate (that is, the specific power when the part is heated) is greater than or less than the corresponding heating rate, unreasonable or undesirable quenching will also occur Organization, if the heating rate of the induction heating equipment is less than the corresponding heating rate, the workpiece will be heated to the determined quenching temperature, and the superheated structure will be obtained after quenching. If the acceleration is greater than the corresponding heating rate, the workpiece will be heated to the determined quenching temperature, after quenching A quenched structure with sufficient heating will be obtained. Therefore, when selecting the quenching temperature for the steel bar quenching and tempering treatment line, not only the composition of the material and the original structure must be considered, but the influence of the heating speed must also be considered.