Iridium mechanical properties

Platinum alloys containing from 0 5 to 20 per cent, of tantalum are hard, withstand heat, as well as the action of adds and fused potassium hydrogen sulphate, and are more resistant to the action of aqua-regia than platinum.8 They possess the mechanical properties off platinum-iridium alloys and are less expensive the relative quantities, of tantalum and iridium required to produce the same hardness and mechanical resistance are stated to be 1 5. Platinum-tantalum alloys, hence have been recommended for various purposes in place of platinum or platinum-iridium. Tantalum can also be coated with platinum, andl can then be utilised in high-temperature work. ... 

Titanium activated with oxides of different metals, in particular mthenium or iridium, used in the form of mesh, wire or strip, is the most reliable and widely used type of anode [51]. It has good mechanical properties and can easily be adapted to the entire surface of the structure in order to obtain a good distribution of current It is usually coated with an overlay of mortar but can also be embedded directly into the concrete. It can dehver current densities up to 100 mA/m over long periods, with short-term maximum levels of even 300-400 mA/m. Laboratory tests and field experience indicate that the service hfe can range from 20 to over 100 y (if the quahty of concrete and overlay are adequate). 

Pure platinum is relatively soft and is used in light-duty applications on sensitive relays and instruments. When alloyed with iridium, greater hardness and mechanical properties can be obtained, leading to its use in medium-duty applications. 

Using Dye/amine/alkyl bromide, iridium-containing photoluminescent polyacrylate films have also been manufactured. Polyoxometallate (POM)/polymer hybrid materials exhibiting modified mechanical properties (polymerized EPOX/TMPTA matrix with inserted POM clusters [XIA 15]) were synthesized in a one-step process using a silicon or phosphor polyoxomolybdate/iodonium salt/silane system. 

Hardness of the aimealed metals covers a wide range. Rhodium (up to 40%), iridium (up to 30%), and mthenium (up to 10%) are often used to harden platinum and palladium whose intrinsic hardness and tensile strength are too low for many intended appHcations. Many of the properties of rhodium and indium. Group 9 metals, are intermediate between those of Group 8 and Group 10. The mechanical and many other properties of the PGMs depend on the physical form, history, and purity of a particular metal sample. For example, electrodeposited platinum is much harder than wrought metal. 

Iridium metal compounds have shown some remarkable effects recently for luminescent properties such as very high photoluminescent quantum yields [27, 29, 44] and high stability [46]. Two reviews [2, 4] have recently reported on phosphorescent heavy-metal complexes (Re, Ru, Os, Ir, and Rh) as bioimaging probes, including their photophysical properties, cytotoxicity, and cellular uptake mechanisms [2], and on transition metals (Ir, Re, Ru) in fluorescent cell imaging applications such as uptake and toxicity [4], respectively. 

Anodic Electrochromic Materials. The most commonly used anodic electrochromic materials are nickel oxide (Svensson and Granqvist [1986]) and iridium oxide (Gottesfeld et al. [1978]). They switch from a transparent state to a colored one upon extraction of protons. Charge-balancing electrons are simultaneously extracted from the valence band. The films are probably a mixture of oxide and hydroxide components in the bleached state, since there needs to exist a reservoir of protons in the films. Due to the high cost of iridium, the use of nickel oxide is favored for large scale appfications. Recently, a class of mixed nickel oxides with enhanced modulation between the transparent and the colored state have been discovered (Avendano et al. [2003]). Intercalation of Li into ifickel oxide films has been attempted, but the optical properties are not modulated very much (Decker et al. [1992]). The mechanism of optical absorption is not known in detail. However, in... 

---