Effect of heat input on HAZ softening in fiber laser welding of 22MnB5 steel

TUNÇEL O., AYDIN H., Davut K.

OPTICS AND LASER TECHNOLOGY, cilt.164, 2023 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 164
  • Basım Tarihi: 2023
  • Doi Numarası: 10.1016/j.optlastec.2023.109560
  • Dergi Adı: OPTICS AND LASER TECHNOLOGY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, Applied Science & Technology Source, Communication Abstracts, Computer & Applied Sciences, INSPEC, Metadex, Civil Engineering Abstracts
  • Anahtar Kelimeler: Fiber laser welding, 22MnB5 steel, HAZ softening, Mechanical properties, Microstructure, HIGH-STRENGTH STEEL, WELDED DISSIMILAR JOINTS, MECHANICAL-PROPERTIES, FATIGUE PROPERTIES, LOW-ALLOY, MICROSTRUCTURE, BEHAVIOR, TENSILE
  • Bursa Uludağ Üniversitesi Adresli: Evet

Özet

This study investigates the effects of heat input on the heat-affected zone (HAZ) softening in fiber laser welding of quenched 1.1 mm thick 22MnB5 steel. Laser power (1500-2500 W) and welding speed (40-120 mm/s) parameters are considered as the input process variables. Depending on the input parameters, the applied heat input varied between 12.5 and 62.5 J/mm. The results indicate that a minimum heat input of 50 J/mm is required for full weld penetration. Microhardness findings revealed that the drop in hardness in the HAZ region relative to the base material (BM) reached 39% due to grain coarsening caused by an increase in heat input under the welding conditions. Grain coarsening (prior austenite grains) is also detected in SEM analysis. In addition, grain coarsening at high heat input was also determined quantitatively in EBSD analyses. The proportion of 8.91 mu m grain size in the sample with high heat input is 4.2%, while it is 1.2% in the sample with low heat input. When the heat input increased from 12.5 to 62.5 J/mm, the width of the softened zone with the lowest hardnesses in the HAZ grew from 0.2 mm to 2.2 mm.