Mechanical and corrosion behaviour of hot stamped 22MnB5/Usibor 1500 steel alloy Yb:YAG continuous fiber laser weldments

摘要

The hot stamped 22MnB5/Usibor 1500 is one of the best steel alloys used today in the car manufacturing industry. Therefore, the welding and their effect on the properties of this alloy is the study concern for the application. The aim of this work is to investigate and compare between the metallurgical, mechanical, and corrosion behavior of butt welding of 22MnB5 without Al/ Si layer and with Al/Si layer (Usibor 1500) steels. The welding was carried out byYb:YAG continuous fiber laser with material thickness 1.0 mm. The welding bead slightly increases with the increase of laser welding velocity. The heat affected zone (HAZ) width isinversely proportionate to the laser welding velocity. AlthoughUsibor 1500 steel undergoes a martensite structure, however its structure in the HAZ and fusion line is dependent on laser welding velocity. Higher ferrite content was observed in the HAZ with higher laser velocity. The hardness distribution was significantly affected with the changes in the microstructure. Electrochemical corrosion testing was used to evaluate the corrosion behaviour of the welded workpieces. The welded material is more susceptible to pitting than the un-welded material. Higher corrosion resistance was obtained in case of coated than rather uncoated workpieces.