What is the reason for cracking of Q235NH weathering steel?

1. Poor weldability, resulting in inability to weld. Set up suitable welding conditions.
2. Dressing defective welding parts, resulting in defective welding. Precautions in the cutting process.
3. Welding pollution (oil, water, dust removal) set the appropriate welding pollution after welding speed.

Preventive measures: after heat treatment - blanking: quenching and annealing sites;
Choose materials with excellent molding; The cracking rate can be reduced by improving the lubrication condition, cracking and surface state of Q235NH weathering steel, although there is no direct cause.