Structure and properties of welded joints in large thick-wall structures made of 25L steel welded without preheating

Selected from Svarochnoe Proizvodstvo 2017(4) 3–7.

Abstract

The effect of welding without preheating is investigated and the effect of additional operations by the transverse hill method on mechanical properties and structure-welded joints in 25L steel is studied and compared with properties after welding with preheating and high-temperature tempering. It is shown that after welding without additional operations, the heat-affected zone is characterized by the formation of a structure of upper granular bainite resistant to brittle fracture. The impact and ductility properties of this structure are higher than the requirements imposed on the parent metal.

Keywords:

• Steel
• welding
• transverse hill
• preheating
• tempering
• structure
• grain
• bainite
• properties
• brittle fracture

Notes

Selected from Svarochnoe Proizvodstvo 2017(4) 3–7.