The thermodynamic properties were reviewed by the author in 1995. A new assessment of the enthalpy of fusion at 68.0 ± 1.7 kJ mol⁻¹ leads to a revision of the thermodynamic properties of the liquid phase and although the enthalpy of sublimation at 298.15 K is retained as 788 ± 4 kJ mol⁻¹ the normal boiling point is revised to 5565 K at one atmosphere pressure.

Platinum-20% rhodium strengthened by oxides of zirconium and yttrium were prepared by solidification of platinum-rhodium-(zirconium)-yttrium powder which had been internally oxidised. After forging, rolling and annealing, 1 mm plates were obtained. Then the plates were mechanically ground to 50–70 μm from rolling-normal direction, followed by argon ion milling until a hole appeared on the centre of the foil to obtain samples which were characterised by transmission electron microscopy (TEM), combined with thermodynamic analysis. The existence of spherical ZrO₂ and Y₂O₃ particles was verified with platinum and rhodium present as pure metals at the same time. It was found that the deformation behaviour of ZrO₂ and Y₂O₃ particles was quite different during processing, where the former basically maintain their spherical shape and were bonded tightly to matrix, while the latter were compressed along normal direction and form two cracks on both sides of Y₂O₃ particles along the rolling direction. The differences in hardness and interface bonding properties of these two types of particles are supposed to be the main causes of different deformation behaviour during hot forging and cold rolling.

Deformation and fracture behaviour of cold drawing iridium wire under tension at room temperature is examined. High purity polycrystalline iridium was manufactured using pyrometallurgical technology. During the initial stage of cold rolling, iridium wire has its usual grain structure and exhibits brittle deformation behaviour: poor plasticity and brittle transgranular fracture (BTF). However, the wire begins demonstrating high plasticity including necking in spite of the brittle fracture mode when the lamellar structure has been formed in iridium during cold drawing.

BIORECOVER brings together diverse expertise with the goal of developing a new sustainable and safe process, essentially based on biotechnology, for selective extraction of critical raw materials (CRMs), rare earth elements (REE), magnesium and platinum group metals (pgms). The four-year European Union (EU) H2020 project involves 14 international partners from mining, microbiology, chemistry, engineering, metallurgy, sustainable process development, as well as CRM end-users. Starting from relevant unexploited secondary and primary sources of CRMs, BIORECOVER will develop and integrate three stages for CRM extraction: (a) removal of major impurities present in raw materials; (b) mobilisation of CRMs through use of microorganisms; and (c) development of specific technologies for recovering metals with high selectivity and purity that meet the quality requirements for reuse. Downstream processes will be developed and recovered metals will be assessed by end-users. Modelling and integration of the modular stages and economic and environmental assessment will be done to develop the most effective and sustainable process. This short feature describes the aims and approach, project technologies and intended outputs of the BIORECOVER project.