Titanium heat capacity

Prom the following thermodynamic data, with the assumptions that the heat capacities of reaction are negligible and that standard conditions (other than temperature) prevail, calculate the temperatures above which (a) carbon monoxide becomes the more stable oxide of carbon, in the presence of excess C (6) carbon is thermodynamically capable of reducing chromia (Cr2Os) to chromium metal (c) carbon might, in principle, be used to reduce rutile to titanium metal and (d) silica (taken to be a-quartz) may be reduced to silicon in a blast furnace. 

Titanium metal is used as a structural material in many high-tech applications such as in jet engines. What is the specific heat of titanium in J/ (g °C) if it takes 89.7 J to raise the temperature of a 33.0 g block by 5.20°C What is the molar heat capacity of titanium in J/(mol °C) ... 

Heat capacity estimated by comparison to the other zirconium halides and titanium halides. Entropy estimated from additive constants. 

There are two enthalpy studies (j, 2) covering the liquid region of titanium. The work of Treverton and Margrave ( ) was adopted. A glass transition is assumed at 1300 K below which extrapolated B-Tl heat capacity values are used. The entropy is calculated in a manner similar to that used for the enthalpy of formation. 

Dugdale JS, Morrison JA, Petterson D (1954). The effect of particle size on the heat capacity of titanium dioxide. Proc R Soc London Ser A 224 228-235... 

Properties Dense, silvery solid. D 19.0, mp 1132C, bp3818C, heat of fusion 4.7 kcal/mole, heat capacity 6.6 cal/mole/C. Strongly electropositive, ductile and malleable, poor conductor of electricity. Forms solid solutions (for nuclear reactors) with molybdenum, niobium, titanium, and zirconium. The metal reacts with nearly all nonmetals. It is attacked by water, acids, and peroxides, but is inert toward alkalies. Green tetravalent uranium and yellow uranyl ion (U()2") are the only species that are stable in solution. 

The thermal functions of Zr(g) listed in Table V-7 are those derived by [85CHA/DAV] (or calculated from those values listed by [85CHA/DAV]). The equations listed above for the heat capacity of zirconium gas and equations for other thermodynamic properties derived from these equations reproduce the values listed in Table V-7 to within 0.5%. As is evident from the data presented in the table, the heat capacity exhibits a maximum at about 435 K and a minimum at 975 K. This behaviour also occurs for other metals such as titanium and iron. 

This is an investigation of the heat capacity of zirconium, titanium and zirconium alloys using an adiabatic calorimetry technique in the temperature range 60 lo 960°C. Two samples of zirconium were studied and nine separate experiments were accepted by the authors. However, all experiments exhibited a maximum in the heat capacity between 180 and 250 C, a feature which is inconsistent with previous or subsequent studies of the heat capacity or enthalpy of the metal, fhe position of the maximum varied from run to run. I lic author e.xplaincd the peak as being due to the presence of an amount of zirconium hydride in the sample and provided some evidence for the observed behaviour, demonstrating that as little as 0.26% hydrogen (28.5 ppm) could explain the results obtained. If this explanation was correct, each of the runs would contain a differing... 

A comparison of thermophysical and thermomechanical properties for all three alloys is given in Table 7.12. Values for thermal conductivity, heat capacity, density, thermal diffusiv-ity, flow stress (800 °C, or 1470 °F, and strain rate =10 s ) and beta-transus temperature are given. Also recall that the CP titanium alloy has an hep crystal structure, the Ti-15-3 alloy has a bcc structure, and the Ti-6A1-4V alloy has a dual hcp/bcc structure. Furthermore, it is important to note that the total alloy content increases from CP titanium to Ti-6A1-4V to Ti-15-3. Study of the various properties suggests that ease of welding may be dependent on crystal structure, thermal conductivity, and beta-transus temperature. However, much more work is needed to understand differences in the FSW response of the three alloys. 

If there is an operation bottleneck because of lack of heating capacity of a furnace in this temperature range, control techniques are available to increase capacity by raising the temperature of the furnace above the final product temperature. If bright metals such as stainless steel or titanium are to be heated, the rate of radiation will be low because of their lower emissivity (eq. 2.6) therefore, convection velocity should be increased. An excess of furnace or gas temperature over the desired final load temperature is permissible with steel provided the hottest location has a T-sensor to automatically control heat head. A fiue gas temperature somewhat higher than the final load temperature can be used with aluminum because of its lower absorptivity and higher thermal conductivity. 

The specimen is initially in thermal equilibrium at an elevated temperature in a furnace. An increment in temperature of a few kelvins is produced by delivering a pulse of electrical energy to the specimen, one heat capacity value being obtained for each pulse. This procedure is then repeated for different starting temperatures. For example, Parker measured the enthalpy of transformation a- to P-titanium at 1155.6 K. 

Specific heat capacity MJ m-= K-1 1.66 1.03-1.541 (titanium dioxide composite) V feng, S Zhang, J Liu, L Yang, F Zhang, Y, Solar Energy Mater. Solar Cells, 143, 120-7, 2015. 

Heat capacities of titanium carbides and nitrides as a function of temperature. (From Ref. 

Bro] Bros, J.P, Michel, M.L., Castanet, R., Enthalpy and Heat Capacity of Titanium Based Alloys , J. Thermal Analysis, 41, 7-24 (1994) (Experimental, Thermodyn., 6)... 

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