Manganese twinning induced plasticity (TWIP) steels are attractive materials for the automotive industry thanks to their combination of strength and excellent toughness. This article deals with basic microstructural and mechanical properties of sheet metal of two heats of low-carbon medium-manganese steel with different aluminium levels. Microstructure observation was carried out using optical and scanning electron microscopy. Electron backscatter diffraction (EBSD) and X-ray diffraction were used for phase analysis. In an experiment that focused on the weldability of both materials, sheet metals were laser-welded using various laser power settings, with and without shielding gas. Various combinations of joints between materials of the two heats and sheet metal conditions were tested (work-hardened upon cold rolling + annealed). Mechanical properties of the weld joints were determined using miniature tensile testing and conventional hardness measurement. The strengths of miniature specimens of the weld metal were very close to the strength of the base material.

The various process-specific differences in techniques compared to traditional techniques can produce significantly different mechanical behaviour in additively manufactured (AM) parts compared to traditional bulk counterparts. Components produced by AM are built layer by layer via localised melting. Therefore, both location- and orientation-dependent properties can be expected. Since many AM parts take advantage of the design and topology freedom provided by AM, properties characterisation with the use of standard specimens is not always possible, requiring the use of small-sized specimen techniques. In the current paper, three AM-produced IN-718, Ti-6Al-4V and H13 parts using electron beam powder bed fusion and laser powder bed fusion are evaluated. Local mechanical properties have been assessed with the use of mini-tensile tests that were developed for cases where limited amounts of material are available. The results obtained demonstrate the ability to measure location- and orientation-dependent properties in AM components using such approaches and highlight that additional work by the AM community remains in order to determine the source(s) of such differences.

The strengthening effects of Cu and Mn were studied in steels, which contained 0.2% C and were micro-alloyed with B and Ti. The experimental steels were austenitized and quenched in order to take Mn and Cu into solid solution. The subsequent tempering of martensitic structures resulted in higher strengths in the materials alloyed with Cu than in the steel without Cu addition. Tensile testing and metallographic analyses were performed. The kinetics and magnitude of precipitation strengthening were measured for different tempering temperatures and times. Presumed synergistic effects between Cu precipitation strengthening and higher levels of Mn were observed.