Open AccessTechnology of thermal welding with ultrasonic weld joint treatment as applied to NPP formworks
Author(s) -
Sergey Ivanovich Minin
Publication year - 2017
Publication title -
nuclear energy and technology
Language(s) - English
Resource type - Journals
ISSN - 2452-3038
DOI - 10.1016/j.nucet.2017.07.005
Subject(s) - welding , materials science , joint (building) , residual stress , electric resistance welding , plastic welding , metallurgy , deformation (meteorology) , ultrasonic sensor , heat affected zone , composite material , ultrasonic welding , structural engineering , filler metal , arc welding , engineering , physics , acoustics
Increasing the strength, reliability and durability of welded structures is an important problem in welding engineering. A significant influence is exerted by residual stresses. Uneven heating of the product during welding causes its uneven temperature deformation. The product material solidity prevents the free temperature deformation of its individual parts, resulting in the formation of stresses and plastic deformation of some parts of the joint metal during welding, and after cooling, welding stresses and deformations remain in the product.The paper describes an innovative technology of thermal welding with ultrasonic weld joint treatment as applied to aluminum sliding formworks used in NPP construction. Ultrasonic treatment in the process of welding greatly increases the strength of formwork weld joints by reducing their residual stresses, grain size and degassing. The structure and properties of aluminum welds become identical to the base metal. Thermal welding with ultrasonic weld joint treatment will improve the reliability of welded joints and increase their time in service. The paper presents the results of theoretical and experimental studies of ultrasonic effects on the welded joints and heat-affected zone