In the processing and production of hardware Spring, there are always a variety of small problems, so how to deal with it?

If air furnace heating quenching does not protect gas or salt bath deoxidization is not enough, it may cause decarbonization, the solution is air furnace heating quenching should pass protection gas or drop organic solution protection,salt bath should be deoxidized when salt bath furnace heating, impurity BAO mass fraction less than 0.2; strengthen the surface quality inspection of raw materials.

2. if the hardness is insufficient after quenching, the service life of the hardware spring will decrease and the residual deformation. Solution is to choose steel with good harden-ability, improve the cooling capacity of quenching medium, the temperature of metal spring entering quenching medium should be above AR3, raise the heating temperature of quenching properly, and make metallographic structure test after strengthening quenching.

3. temperature overheating will cause coarse grains and increase brittleness. Solution is to do heating and quenching according to the correct temperature of process test; reducing the thermal forming temperature appropriately or strengthening the proofreading of the instrument to ensure the accuracy of temperature measurement.

4. cracking is mostly happen due to high thermal temperature or excessive cooling capacity of quenching medium, surface decarbonization and untimely tempering. Solution is to use isothermal quenching or martensite grading quenching; cold in quenching medium to 250~300 oC take out air cooling; tempering immediately after quenching