Titanium commercially pure grade

The mechanical properties of titanium are greatly affected by small amounts of oxygen and nitrogen. The properties of the commercially pure grade metal and its alloys are given in the Table 3.35. 

Titanium Corrosion Rate Data- Commercially Pure Grades... 

In commercially pure grade 2 titanium, the allotropic transformation from a hep a-phase to a bcc P-phase occurs at -915 0. Transitions from a P-Ti bcc pattern at high temperature inside the HAZ, to a a+p-mixed zone, and eventually to the a-Ti hep pattern have been recorded in real time. In addition to phase transformations, the material undergoes annealing and re-crystallization in the cooler region and outside of the HAZ. SRXRD data obtained from different starting positions with respect to the weld center may... 

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. 

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. 

The choice of metals is highly restricted. The only metals found satisfactory and in wide use are titanium, tantalum, and precious metals. Of these, only titanium is used in quantity for the construction of equipment. Its application is straightforward, and commercially pure metal (Grade 2) is satisfactory without alloying. The other metals listed above are used primarily in instruments and other small items. The ban on the large majority of metals extends to their use in auxiliary systems. Copper, for example, is used in many industrial water systems. It should not be used with hleach dilution water, however, because of its catalysis of hypochlorite decomposition reactions. 

Titanium grade 2 or commercially pure titanium is the most common titanium alloy for corrosion applications. The titanium grade 7 alloy, which contains a small amount of Pd, has better corrosion-resistance than Ti Gr 2 it is, however, more expensive. The corrosion performance of titanium grade 12 is generally between those of Ti Gr 2 and Ti Gr 7 alloys and it is sometimes used as a less expensive alternative to Ti Gr 7 (Covington and Schweitzer, 1989). Table 2-19 shows the comparative corrosion performance of these three titanium alloys in a variety of environments. 

High-purity titanium has one-half the oxygen content as commercially pure (ASTM grade 1) titanium. High-purity titanium is produced finm a special grade of titanium sponge (<0.1 wt% oxygen). 

Commercially pure titanium is available in several grades, which have varying amounts of impurities such as carbon, hydrogen, iron, nitrogen, and oxygen. Some modified grades also contain small palladitim additions (Ti-0.2 Pd) and nickel-molybdemun additions (Ti-0.3Mo-0.8Ni). These alloy additions allow improvements in corrosion resistance and/or strength. 

Titanium is not a cure-all for every corrosion problem, but increased production and improved fabrication techniques have brought the material cost to a point where it can compete economically with some of the nickel-base alloys and even some stainless steels. Its low density offsets the relatively high materials costs, and its good corrosion resistance allows thinner heat-exchanger tubes. Table 8.42 presents the corrosion rates observed on commercially pure titanium grades in a multitude of chemical environments. ... 

TABLE 8.42 Corrosion Rates of Commercially Pure Titanium Grades... 

Titanium Alloys Commercially pure (ASTM grade 1) 4.51 0.163... 

Commercially pure ASTM grade 1, annealed TITANIUM ALLOYS 100.00-120.00 85.6... 

The intermetallic compounds were prepared from the best grade of metals commercially obtainable. The rare earth metals, obtained from Research Chemicals, Inc., were 99.9% pure, and cobalt and nickel, obtained from the United Mineral Corp., were 99.999% pure. After each element was weighed to obtain the correct stoichiometric amounts, the compounds were formed by induction melting in a water-cooled copper boat under an argon atmosphere, purified by passage through a titanium-gettering furnace. 

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