Influence of Gas Tungsten Arc Welding Parameters in Aluminium 5083 Alloy
The present work deals with the identification of the best combination of welding parameters, in TIG welding of Aluminium alloy 5083. In this study two level full factorial experimental design is considered which consists of two factors and two levels. Inorder to avoid experimental errors two replications are performed for each experimental combination. The working ranges of welding parameters for conducting experiments are initially obtained by trial and from literature survey. After the experiment, various tests like Tensile test; Microhardness, Macrostructure and Microstructure study are conducted to the welded specimens. The analysis of the test results is conducted and the combination of welding parameter ranges that gives best result is found. This combination can be considered as good working ranges for TIG welding of Aluminium alloy 5083.
Review of GTAW Welding Parameters
Welding as a fabrication process is one of the vital production routes for most manufacturing industries. Several factors are involved in the choice of welding process for specific applications; notable among these are compositional range of the material to be welded, the thickness of the base materials and type of current. Most metals oxidize rapidly in their molten state, and therefore, the weld area needs to be protected from atmospheric contamination; this is achieved in gas tungsten arc welding GTAW by a shielding gas (argon, helium, nitrogen). GTAW technique is one of the major processes for joining austenitic stainless steels (ASS) and ferritic stainless steel (FSS) fabrication. However, the microstructural change that occurs during welding and at weld joint is still a major challenge today as it affects both the corrosion resistance and the mechanical properties. Therefore, this present paper reviews past research findings on GTA welding of ASS and FSS. Results of the findings have confirmed that, depending on the amount of heat input, which can be controlled by welding parameters (welding speed, voltage and current), welded joints particularly, heat affected zones (HAZs) of both grades of steels can undergo mechanical failure and can be susceptible to corrosion attack if the joints are produced with a less ideal combination of welding parameters.
Effect of ECAP pass number on mechanical properties of 2A12 Al alloy
Abstract2A12 Al alloy was suffered from equal-channel angular pressing(ECAP) in this experiment. The influence of ECAP pass number on ultimate strength(UTS), hardness and elongation was studied. The results show that during ECAP the number of sample passing through the channels is very important for mechanical properties and microstructure refinement. ECAP not only increases their plasticity and hardness but also leads to refined grain. But the elongation reduces from 17.5% to11.8 % after 1 pass ECAP, then almost tends to be unchanged with the increasing of pass number. The value of ultimate strength of 2A12 Al alloy increases by 135%, hardness by 51%, and ultra fine grains of about 200 nm can be observed after 8 passes.