Titanium wear properties

Titanium Carbonitride. Titanium carbonitride (TiCJSfi.x) combines the wear properties of TiC with the low friction and oxidation and chemical resistance of TiN. It is obtained in a hydrogen atmosphere and at a temperature of approximately 1000°C by the following simplified reaction ... 

The second form consists of Pt metal but the iridium is present as iridium dioxide. Iridium metal may or may not be present, depending on the baking temperature (14). Titanium dioxide is present in amounts of only a few weight percent. The analysis of these coatings suggests that the platinum metal acts as a binder for the iridium oxide, which in turn acts as the electrocatalyst for chlorine discharge (14). In the case of thermally deposited platinum—iridium metal coatings, these may actually form an intermetallic. Both the electrocatalytic properties and wear rates are expected to differ for these two forms of platinum—iridium-coated anodes. 

Titanium (TiC) is an important industrial material produced extensively by CVD. It is an excellent refractory material which is unusually hard with high strength and rigidity and outstanding wear resistance. Its properties are summarized in Table 9.8. 

Titanium Carbonitride. Ti(C,N) is a solid solution of TiC and TiN and combines the properties of both materials. It offers excellent protection against abrasive wear and has good lubricating characteristics. It is used to coat tools and dies for the processing of ceramics, graphite, and filled plastics. 

Ferro-alloys Master alloys containing a significant amount of bon and a few elements more or less soluble in molten bon which improve properties of bon and steels. As additives they give bon and steel better characteristics (increased tensile sbength, wear resistance, corrosion resistance, etc.). For master alloy production carbothermic processes are used for large-scale ferro-sihcon, ferro-chromium, ferro-tungsten, ferro-manganese, ferro-nickel and metallothermic processes (mainly alumino and sihco-thermic) for ferro-titanium, ferro-vanadium, ferro-molybdenum, ferro-boron. 

Janes, Neumann and Sethna ° reviewed the general subject of solid lubricant composites in polymers and metals. They pointed out that the reduction in mechanical properties with higher concentrations of solid lubricant can be offset by the use of fibre reinforcement. Glass fibre is probably the most commonly used reinforcing fibre, with carbon fibre as a second choice. Metal and ceramic fibres have been used experimentally to reinforce polymers, but have not apparently been used commercially. To some extent powders such as bronze, lead, silica, alumina, titanium oxide or calcium carbonate can be used to improve compressive modulus, hardness and wear rate. 

Transition element carbides and nitrides are applied as cutting tools because of their extreme hardness and wear resistance. In some cases nitrides and carbides (e.g., of titanium) form solid solutions over the entire compositional range other transition metal nitrides and carbides exhibit fairly different structures and are not completely soluble. Carbon contents within the range of few percentage points usually do not influence the mechanical properties of transition metal nitrides, and vice versa. Hence, completely carbon-free nitrides or nitrogen-free carbides are not required, especially for the titanium compounds. 

Pan Y, Xiong D, Ma R (2007) A study on the fiiction properties of poly(vinyl alcohol) hydrogel as articular cartilage against titanium alloy. Wear 262 1021-1025... 

Titanium and its alloys have many biomedical applications due to their high strength and corrosion resistance, and are commonly incorporated in replacement hip joints and items such as bone pins [1]. Porous Ti foams have been explored for biomedical uses due to their enhanced adhesion to host tissue [15]. Surface-treatment of Ti and Ti alloys to enhance material properties, such as wear resistance, in a biomedical context has been examined [16]. In addition, titanium nitride-based materials could potentially serve as coatings for biomedical implants [17]. NiTi-based shape memory alloys are attractive candidates for biomedical materials due to their shape retention and pseudoelasticity, however, manufacturing and processing these memory alloys for biomedical apphcations is typically not straightforward [18]. 

There are a wide range of substrates and films which can be produced as biomaterials. Metals such as titanium alloys are often used where high strength or toughness is required, such as hip implants. Their mechanical properties can be somewhat similar to bone, which makes them ideal candidates as structural bioimplants. However, as outlined by Skinner and Kay (2011), metal erosion can be a potentially dangerous problem. Ceramic films such as Ti02, Si02 or hydroxyapatite Caio(P04)6(OH)2 are often added to the surface to reduce wear of the implant and improve biocompatibUity. 

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