Gear is one important and wide transmission part in mechanical industry, it is mainly used in transmission power, change movement speed and direction. Strictly heat treatment process will improve its quality and machining performance.

(1) working situation

① Due to transfer torque, dedendum bear big alternating bending stress.

② Uneven shift,start or mesh, gear bear certain impulsive load.   

③ Rolling or sliding contact on Tooth surface,it bears big contact pressure and friction.

(2) Performance requirement

① High bending fatigue strength,contact fatigue strength in order to prevent gear deformation.

② High tooth surface hardness and wear resistance in order to prevent wear of tooth surface.

③ Excellent heart strength and tenacity in order to improve load weight of gear.

④ Excellent cutting process and heat treatment process.

(3) Select material

① Gear material usually select middle carbon steel and middle carbon alloy steel with excellent mechanical property.such as:45 steel,1045,S45C,C45...

② Gear bear bigger implusive pressure, it should selects alloy carburizing steel,such as 20Cr,20Cr MnTi,5120,SCr420,20Cr4...

(4) Case

Gear on machine tool( Picture 1), 

Stress of gear on machine tool is not big during working, medium revolving speed, stable working, no strong shock,generally it selects middle carbon steel, after hardening and tempering,heart has enough and high tenacity, it can bear bigger bending stress and impulsive load. The surface adopt high frequency quenching, hardness reaches 52~55HRC, wear resistance is high.

The heat treatment process route is below:

Cutting stock--forging--normalizing--rough machining--hardening and tempering--precious machining--high frequency quenching and tempering--precious grinding

(5) Heat treatment equipment requirement

① Normalizing need car bogie furnace.(picture 2)

② Hardening and tempering need high temperature heat treatment furnace.(picture 2)

③ high frequency quenching need surface heat treatment.(picture 3)

If you have any request on these heat treatment equipment, please contact us! Email:[email protected]