Friction-stir-welding (FSW) technology has been growing since it was patented in 1991 at TWI. Since then the majority of research and industrial applications for joining aluminium alloys were made on wrought aluminium alloys. Lately several investigations have been done in FSW of dissimilar alloys. FSW also has a big potential in the casting industry – especially in high-pressure die casting (HPDC). In this article an investigation of a FSW dissimilar joint made from a casting aluminium alloy (AA413.0) and technically pure aluminium (AA1050) was done. This kind of joint can be used to make an assembled casting, joined with FSW with the aim to have a casting with different material properties or to join HPDC with FSW to assemble a casting with inner cavities. In this article the temperature distribution of the FSW joint of a cast aluminum alloy and technically pure aluminum is investigated. In the experimental work several FSW parameters were tested: the tool speed, the tool rotation and the position of the tool regarding the joint center. During joining the temperature was measured with a thermocouple and the temperature distribution in steady state was calculated with the FEM program Sysweld. The microstructure and mechanical properties of the joint were investigated.
COBISS.SI-ID: 1264991
Joining Advanced Pore Morphology (APM) sandwich panels with Friction Stir Welding (FSW) has been investigated in this work. APM foam based sandwich panels are compound of APM foam bonded to two 1 mm thick sheets of EN AW 6082-T6 aluminium alloy. Several different designs of butt joint were investigated with and without additional material between panels. A classic tool for FSW was used with tilt angle of 1.5°. Tool rotation speed was constantly 1900 min-1. Welding speed varied from 95 to 235 mm/min. Through several iterations, the parameters were changed together with joint design. From the visually acceptable joints specimens for macrographs and mechanical testing were prepared. Charpy impact test and tensile strength test were conducted for visually acceptable joints. A joint design with welding parameters was determined at which acceptable welds can be obtained. Preposition for the further research is to increase the number of samples considering investigation of higher welding speed. The unique properties of APM sandwich panels make them an attractive alternative as a cost effective and easily applicable material that can be joined with FSW.
COBISS.SI-ID: 13353499
This paper presents the preliminary test of tungsten heavy alloy as a filler metal for repair welding of high pressure die casting dies. H13 grade hot work tool steel was used as a base material. Multipass gas tungsten arc welding was used to fill a single-V butt joint with tungsten heavy alloy in the form of a welding rod. The microstructure of the weld was examined using scanning electron microscopy and optical microscopy. It was found that tungsten grains are not dissolved completely during welding and areas of fine eutectic were formed during solidification of the weld. The hardness of the weld was measured in three courses across the weld and increased in the heat affected zone while the weld hardness was below 380 HV0.3. Charpy V-notched samples were prepared from the weld. The high content of tungsten grains distributed in the nickeliron weld matrix resulted in low impact toughness of 5.1 J. Face bend testing of the weld was conducted in order to study weld ductility.
COBISS.SI-ID: 13223451