Commercially pure titanium

(1965) Trans, of Central Research Institute for Ferrous Metallurgy, Moscow, Russia. 43,69-80. Passivation is required to prevent pyrophoricity. 

Standard Specification for Titanium and Titanium Alloy Strip, Sheet, and Plate. ASTM B265-99 (8 pp) 

Engineering Aerospace Military Enginee- ring Aero- space Aerospace Engineer- ing Aerospace 

Apart from the ASTM grades, the world s largest titanium producers have proposed their own commercial designations for grades. For example, the commercial designations according to several of the chief titanium producers are listed in Table 4.50. 

ASTM (B265) Titanium Industries Cabot Performance Materials IMI Limited RMI Titanium Company TIMET (Titanium Metal Corp.) 

---

Table 5.13 Physical properties of commercially pure titanium...

The mechanical properties of titanium are affected by small amounts of oxygen and nitrogen in solid solution. It is therefore possible to produce a number of grades of commercially pure titanium, with mechanical properties suited to the different applications for which the material is intended. 

Resistance to stress-corrosion cracking Commercially pure titanium is very resistant to stress-corrosion cracking in those aqueous environments that usually constitute a hazard for this form of failure, and with one or two exceptions, detailed below, the hazard only becomes significant when titanium is alloyed, for example, with aluminium. This latter aspect is discussed in Section 8.5 under titanium alloys. 

For commercially pure titanium, the specific environments to be avoided are pure methanol and red, fuming nitric acid " , although in both environments the presence of 2% of water will inhibit cracking. On the other hand, the presence of either bromine or iodine in methanol aggravates the effect. When it does occur, stress-corrosion cracking of commercially pure titanium is usually intergranular in habit. 

The stress-corrosion cracking hazard for titanium alloys containing aluminium is significantly higher than that obtaining for commercially pure titanium, and in addition to stress-corrosion cracking in methanol and red... 

The most recently developed anode for the cathodic protection of steel in concrete is mixed metal oxide coated titanium mesh The anode mesh is made from commercially pure titanium sheet approximately 0-5-2mm thick depending upon the manufacturer, expanded to provide a diamond shaped mesh in the range of 35 x 75 to 100 x 200 mm. The mesh size selected is dictated by the required cathode current density and the mesh manufacturer. The anode mesh is supplied in strips which may be joined on site using spot welded connections to a titanium strip or niobium crimps, whilst electrical connections to the d.c. power source are made at selected locations in a suitably encapsulated or crimped connection. The mesh is then fitted to the concrete using non-metallic fixings. 

Sheet, thin plate, welded tubing, and small-diameter bar of commercially pure titanium are manufactured into parts by conventional cold-working techniques. The formability of titanium, when worked at room temperature, is like that of cold-rolled stainless steel. At 65°C the formability compares with stainless steel annealed at room temperature. Cold-working maybe difficult for some titanium alloys and heat may be required, especially for severe forming operations. Generally, titanium and its alloys are worked between 200 and 300°C. Lubricants reduce friction and galling. Slow forming speeds at controlled rates improve workability and are recommended for more difficult operations. 

The main corrosion problems in a nonacidified condensing sour water stripper occur in the overhead system. Exchanger tubes in the overhead condenser are often made of commercially pure titanium. The reflux pump is often alloy 20 (CN7M). In very corrosive waters, such as those containing phenols or large quantities of salts, Hastelloy1141 C276 is used. Two API surveys (API Standards 944 and 950) concluded that the location and severity of corrosion vary with the type of unit as follows ... 

Commercially pure titanium consists of several grades with increasing amount of oxygen and increase in strength. The versions most used are grades 2 and 3 for tubing, vessels and pipe. 

One of the first studies using r.f. magnetron sputtering performed by Cooley et al. (1992) investigated and compared the healing rates of bone around commercially pure titanium implants and titanium implants sputter-coated from... 

Fig- 7.32 Photograph of the top surface of a friction stir weld on commercially pure titanium. Note the absence of surface oxidation. 

Fig. 7.34 Optical micrograph of the commercially pure titanium base metal...

Table 7.10 Tensile properties of base metal and friction stir welds (FSWs) on commercially pure titanium...

Pure a titanium suffers little damage by hydrogen at low concentrations (<200 ppm), but impurities can greatly increase its sensitivity to hydrogen. Thus, commercially pure titanium exhibits a... 

Oxide-metal composite anodes consist of a mixed ruthenium dioxide and titanium oxide coating sintered onto a commercially pure titanium substrate. These expanded-mesh anodes also are used for protecting reinforcing steel in concrete [37]. 

Due in large measure to the introduction and overall clinical success of the Branemark system, the range of metallic materials utilized for dental implants has become limited largely to commercially pure titanium (cpTi > 99.5%) and its major alloy, T1-6A1-4V [De Porter et al., 1986 Keller et al, 1987]. Controversy remains, largely due to commercial advertising interests, as to which material provides a more suitable... 

Titanium alloys constitute the group of metallic materials showing the highest strength/weight ratio. The density is 4.5 g/cm. A grade widely used under corrosive conditions (the one with the best corrosion properties) is commercially pure titanium. 

---