Effect of weld superpulse time on the microstructural evolution of a low carbon steels

Materia

Raad, Franco¹  Gualco, Agustín² 

[1]Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina

[2]Instituto de Investigación en Soldadura FI-UNLZ, Buenos Aires, Argentina

关键词: pulse welding;    time of pulses;    low carbon steel.;   

DOI  :  10.1590/s1517-707620180002.0354

学科分类：工程和技术（综合）

来源: Universidade Federal do Rio de Janeiro * Coordenacao dos Programas de Pos-Graduacao de Engenharia

【 摘 要 】

The Super Pulse arc type was developed to provide a solution to butt root pass beads in the semi-automatic welding process with gas protection (GMAW). Unlike standard pulse welding, the Super Pulse uses a sequence of different pulse waveforms to create a cord shape and appearance similar to the GTAW process. It uses higher amperage in the primary phase to improve penetration and low amperage in the second phase to reduce the heat input. Spray transfer is used in the primary phase to improve penetration and short arc in the secondary phase to cool the solder bath giving less heat transfer and less distortion to the base material. In the literature there is little information regarding the relationship between the Super Pulse variables and the microstructural characteristics of the deposited metal. The objective of this work was to evaluate the influence of the times of each phase in Super Pulse mode, on the geometric characteristics of the cord and the solidification in weld deposits of low carbon steels. For this purpose, strands should be welded on an IRAM - IAS U500 42 - F24 plate by varying the phase time of the Super Pulse. In cross sections, the geometry of the bead was determined and in longitudinal sections, the microstructure and the characteristics of the molten and affected areas were determined. Preliminary results showed that bead geometry and solidification were strongly influenced by pulse parameters.

【 授权许可】

CC BY