The precipitation of nano-sized Cr clusters was investigated in a commercial Cu-1Cr-0.1Zr (wt.%) alloy processed by equal-channel angular pressing and subsequent aging at 550 • C for 4 h using Small-Angle Neutron Scattering (SANS) measurements and High-Angle Annular Dark-Field-Scanning Transmission Electron Microscopy (HAADF-STEM). The size and volume fraction of the nano-sized Cr clusters were estimated using both techniques. The parameter values assessed by SANS (d ∼ 3.2 nm, Fv ∼ 1.1 %) agreed reasonably with those by HAADF-STEM (d ∼ 2.5 nm, Fv ∼ 2.3 %). In addition to the nano-sized Cr clusters, HAADF-STEM indicated the presence of rare cuboid and spheroid sub-micronic Cr particles measuring approximately 380-620 nm in mean size. Both techniques did not evidence the presence of intermetallic CuxZry phases within the aging conditions.

The aim of this work is to investigate cold worked Ti-6Al-4V (α+β) alloy. The alloy was examined by X-ray diffraction using Rietveld refinement method. MAUD software (Materials Analysis Using Diffraction) was used to analyze the microstructural parameters evolution (crystallite size, root mean square strain (r.m.s) and dislocation density. The Crystallite size is smaller in the β-phase compared to the α-phase. Microstrain and dislocation density are higher in the α-phase than those found in the β-phasefor the as received material. The microstructural parameters of Ti-6Al-4V alloy exhibit typical values of cold deformation state. The results show that the deformation process reducesthe crystallite size (coherent diffraction domains) from 520 to 210 Ȧ in the α-phase. Consequently, the r.m.s increases from 5 E -4 to 32 E -4 and the dislocation density increases from 2.92 E +10 to 4.6 E +11 m -2 after 85 % thickness reduction.

In this work, the micromechanical properties, crystallographic texture, welding residual stresses and their evolution after plastic strain were investigated in a Ti-6Al-4 V alloy tungsten inert gas weld joint. It was found that the welding process affected the Young modulus and microhardness values in both α and β phases in the different regions of the weld joint. The highest microhardness and Young modulus values of α phase were recorded in the heat-affected zone, whereas the highest values of these characteristics for the β phase were found in the fusion zone (FZ). The change in the micromechanical properties was accompanied by a change in the crystallographic texture components of the dominant α phase from (0001) < 10-10 > and (11-20) < 10-10 > components in the base material to (10-10) < 11-20 > and (11-20) < 3-302 > components in the FZ. The introduction of tensile testing resulted in a continuous stress relaxation and improved the weld joint performances.