Mechanical properties testing of structural steel welds are well known and standardized. Results of those testing are important information regarding evaluation and qualification of welding technologies. However, using only standardized testing it is not possible to evaluate the weakest part of welds; e.g. coarse-grained heat affected zone, where peak temperature over 1300 C is reached during fusion welding. Such high temperatures have for consequence significant change and drop of some mechanical properties. Thus, it is important to perform some more sophisticated evaluation and prior preparation of test specimens. Actually, such prior preparation include welding thermo-cycle simulation on test specimen ready for standardized testing. The paper present one combination of testing results, both standardised and sophisticated, for the purpose of more detailed review of mechanical properties of high-strength steel welds with nominal yield strength in the range of 690-890 MPa. Detailed distribution across welds is presented including the following generalised mechanical properties: hardness, strength, toughness. Significant drop of some mechanical properties is observed within coarse-grained heat affected zone, which may require particular attention within everyday engineering practice.

Aluminium and its alloys represent very important group of structural materials. They have many applications in mechanical and civil engineering, and welding is considered to be one of the most important joining techniques. However, welding of aluminium has several issues, like high thermal conductivity and easy formation of oxide layer with high melting temperature. Recently, solid state friction stir welding process has been developed to overcome such issues, but it is not easily applicable in every situation. Therefore, welding of aluminium still greatly relies on arc welding. Among commonly used TIG and MIG processes, pulsed MIG (and its variants) are developed to fulfil requests regarding heat input and oxide layer removal during welding. This paper gives brief general overview of technical and technological aspects of these processes, and then more details regarding welding of widely used aluminium 5754 alloy with thickness of 4 mm. Comparison of relevant costs is given as well. All welds were made using digitally controlled equipment, while voltage and current were additionally measured. Based on evaluation of welds and calculated costs, conclusion regarding feasibility of each process is given.