Ti and Ti-TiB composite materials were produced by selective laser melting (SLM). Ti showed an α΄ microstructure, whereas the Ti-TiB composite revealed a distribution of needle-like TiB particles across an α-Ti matrix. Hardness (H) and reduced elastic modulus (Er) were investigated by nanoindentation using loads of 2, 5 and 10 mN. The results showed higher H and Er values for the Ti-TiB than Ti due to the hardening and stiffening effects of the TiB reinforcements. On increasing the nanoindentation load, H and Er were decreased. Comparison of the nanoindentation results with those derived from conventional hardness and compression tests indicated that 5 mN is the most suitable nanoindentation load to assess the elastic modulus and hardness properties. The wear resistance of the samples was related to their corresponding H/Er and H3/Er2 ratios obtained by nanoindentation. These investigations showed that there is a high degree of consistency between the characterization using nanoindentation and the wear evaluation from conventional wear tests

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A comparative study of four series of pyrrhotite-type chalcogenide compounds Fe(7-y)M(y)X(8) (X = S, Se) with substitution of Ti or Co for iron has been performed by means of x-ray and neutron powder diffraction, and by magnetization measurements. In Fe(7-y)M(y)X(8) compounds having a ferrimagnetic order at y = 0, the substitution of either Ti or Co for iron is observed to result in a monotonous decrease of the magnetic ordering temperature, while the resultant magnetization shows a non-monotonous behavior with a minimum around y = 1.0-1.5 in all the Fe(7-y)M(y)X(8) families except Fe(7-y)Co(y)Se(8). Suppression of a magnetically ordered state with substitutions in Fe(7-y)M(y)X(8) is ascribed to nearly zero values of Ti and Co magnetic moments, while the non-monotonous changes of the resultant magnetization are explained by the compensation of the sublattice magnetizations due to the non-random substitutions in alternating metallic layers. The difference in the cation partitioning observed in Fe(7-y)Ti(y)X(8) and Fe(7-y)Co(y)X(8) is attributed to the difference in the spatial extension of Ti and Co 3d orbitals. High coercive field values (20-24 kOe) observed at low temperatures in the Ti-containing compounds Fe(7-y)Ti(y)X(8) with y ⩾ 3 are suggested to result from the enhancement of Fe orbital moment due to the Ti for Fe substitution.