Welding performance and preparation before welding of 35CrMo4 steel

35CrMo4 steel has good welding performance and can be welded by conventional welding methods. However, welding at high temperature for a long time may lead to the growth of grains and the reduction of hardness, so it is necessary to properly control the welding temperature and time so as not to affect the welding quality. In addition, it is recommended to properly preheat the material before welding to improve the strength and toughness of the welded joint.

The welding of 35CrMo4 steel needs to pay attention to the following points:

1. Clean the surface: Before welding, it is necessary to ensure that the surface of the workpiece is clean and free of oil, rust and other debris.

2. Control heat input: Since 35CrMo4 steel has high hardness and toughness, heat input should be controlled during welding to avoid quality problems such as overheating and cracks.

3. Select the appropriate welding material: the appropriate welding material should be selected according to the characteristics and requirements of the workpiece to ensure the quality of the weld.

4. Strictly control welding parameters: including current, voltage, welding speed, gas protection and other parameters to ensure welding quality.

5. Post-weld heat treatment: For some workpieces with high requirements, post-weld heat treatment is an essential step to avoid problems such as deformation and cracks.

Before welding 35CrMo4 steel, the following preparations should be made:

1. Clean the surface of 35CrMo4 steel to remove impurities such as grease and dust.
2. Check the 35CrMo4 steel surface and base metal for defects or cracks.
3. Select the appropriate welding method, electrode, gas and other welding parameters according to the actual situation.
4. According to different welding methods, take corresponding preheating measures to prevent the occurrence of thermal cracks.
5. Carry out trial welding and check the quality of the weld to confirm the feasibility of the welding parameters.