Welding in solid state

The importance of the Solid State Processes (SSP) has increased in the last decade due to the industry demands of improved properties of joined/surfaced materials, combined with cost reduction and energy saving. New and/or micro-scale solid state processed materials are used by aerospace, automotive and electrotechnics industry. Nowadays, classic SSP are mainly applied to light materials, but progresses were also reported in steels. In this field, the tools design, the technology and practical techniques surpassed the fundamental approach of the materials solid state processing. The SSP parameters evaluation is based on different experiments, approaching the material flow in the large plastic deformation domain. The paper approaches the solid state welding/joining and surface processing. The envisaged SSP are solid state joining processes as Cold Welding (butt and spot welding), Friction Stir Welding – FSW, and surface processing, Friction Stir Processing - FSP. Therefore, the investigation targeted the deformation and flow pattern of the parent metal in case of cold welding and FSW/FSP, processes parameters evaluation and correlation, local analysis of the material structural transformations, and material hardening

High Intensity Lasers Application to Advanced Materials Processing: Laser Peening and Related Processes

High Intensity Lasers Application to Advanced Materials Processing: Laser Peening and Relate

TEMPLUM: A Process Adapted Numerical Simulation Code for The 3D Predictive Assessment of Laser Surface Heat Treatments in Planar Geometry

A process adapted numerical simulation code for the 3D predictive assessment of laser heat treatment of materials has been developed. Primarily intended for the analysis of the laser transformation hardening of steels, the code has been successfully applied for the predictive characterization of other metallic and non metallic materials posing specific difficulties from the numerical point of view according to their extreme thermal and absorption properties. Initially based on a conventional FEM calculational structure, the developed code (TEMPLUM) reveals itself as an extremely useful prediction tool with specific process adapted features (not usually available in FEM heat transfer codes) in the field of laser heat treatment applications

Soldadura láser remota de aceros de alto límite elástico

En este artículo se presenta un estudio de soldabilidad del acero de alto límite elástico Usibor 1500 P revestido al Al-Si sin tratar térmicamente mediante soldadura láser remota. La soldadura de este material presenta dificultades debido a que el Al presente en el recubrimiento provoca inclusiones de compuestos íntermetálicos Al-Fe en la unión. Estos compuestos tienen baja ductilidad y fractura frágil a temperatura ambiente, produciendo estos efectos en la unión realizada.- This paper presents a weldability study of Usibor 1500 P high strength steel pre-coated of Al-Si in the non quenched state by remote laser welding. The pollution of the melt pool by Al-Fe intermetallic particles during laser welding results in low strength joints

Overall vs. local mechanical behaviour of ferritic austenitic steel joints made by laser welding

The present investigation addresses the overall and local mechanical performance of dissimilar joints of low carbon steel (CS) and stainless Steel (SS) thin sheets achieved by laser welding in case of heat source displacement from the weld gap centreline towards CS. Welding was performed on a Nd:YAG laser DY033 (3300 W) in a continuos wave (CW), keyhole mode. The tensile behavior of the joint different zones assessed by using a video-image based system (VIC-2D) reveals that the residual stress field, together with the positive difference in yield between the weld metal and the base materials protects the joint from being plastically deformed. The tensile loadings of flat transverse specimens generate the strain localization and failure in CS, far away from the weld

Cold welding on cogged surface

La soldadura por frío entre superficies dentadas es lograda presionando una chapa de aluminio deformable fácilmente por una superficie dentada de un componente más duro. El proceso requiere la limpieza exacta de las chapas en el área de contacto. El empalme se logra solamente por grande deformación plástica del componente del aluminio, que entra entre los dientes del más duro, hecha de cobre, o de acero carbón o inoxidable. El papel presenta el modelo 2D por elemento finito del proceso: Los resultados como tensión elemental y las tensiones en el área de contacto en el componente de aluminio fueron discutidos y comparados con experimentos. Se presentan también la deformación y/o las grietas del aluminio que fluye durante presionar entre los dientes del material más duro, a diversas grados de deformación. El uso industrial más importante del proceso es en electrotécnica, para los empalmes disímiles de aluminio-cobre.-Cold welding on cogged surfaces is achieved by pressing an easy deformable sheet of aluminium on a cogged surface of a harder component. The process requires sheets accurate cleaning in the contact area, where the cold welding is expected to occur. The joint was obtained only by large plastic deformation of the aluminium component on the harder one, made from copper, or carbon/stainless steel. The paper presents the 2D Finite Element Method Model of the process; results as aluminium component elementary strain and stresses in the contact area were discussed and compared with experiments. The aluminium flowing during pressing into the harder material cogs at different deformations, its deformation or cracking are presented, as too. The process industrial application in electrotechnics, to obtaining dissimilar joints of aluminium-copper, is of high importance due to the coupled materials electric properties