Chromium specific heat

Stainless steel accessories in cars are usually plated with chromium to give them a shiny surface and to prevent rusting. When 5.00 g of chromium at 23.00°C absorbs 62.5 J of heat, the temperature increases to 50.8°C. What is the specific heat of chromium ... 

ASTM A 297/A 297M-97(2003) Standard Specification for Steel Castings, Iron-Chromium and Iron-Chromium-Nickel, Heat Resistant, for General Application (contains most of the H grade, e.g., HP, castings)... 

We indicated in our discussion of simple metals that the electronic specific heat at low temperatures is linear in temperature and proportional to the density of states at the Fermi energy. The density of states so obtained from the specific heat is shown in Fig. 20-9, and the correlation is apparent. Notice in particular the low value at four electrons per atom for Ti, Zr, and Hf, all of which occur in the hexagonal closc-packcd structure this corresponds to the dip we noted in the density of states in Fig. 20-8,a. Similarly the minimum at six electrons per atom corresponds to the minimum in the body-centered cubic density of states of Fig. 20-7, at the Fermi energy for chromium. 

Atomic Weight.— Like chromium and molybdenum, tungsten may in its compounds be di-, tri-, or hexa-valent from a consideration of its specific heat, the isomorphism of its compounds, its position in the... 

The specific heat of aq. soln. of chromium trioxide, between 21° and 53°, was measured by J. C. G. de Marignac. E. H. Buchner and A. Prins gave for soln. with the molar ratio CrOs H20 ... 

The specific heat of chromium rich Cr-Ni and Cr-Fe-Mo alloys was measured by [1971Bau] in the temperature range 1.3-4.2 K. Measurements were made for compositions of 20 mass% Mo and 0-20 mass% Fe. This experimental program was intended primarily for the determination of the electronic band stmcture of 3d transition elements. It is known that Cr-Fe alloys exhibit unusual electron specific heat coefficients and an abnormally low Debye temperature, which is attributed to a complex magnetic stmcture of these alloys. The addition of 20 at.% Mo may avoid such complications, as the alloy becomes paramagnetic at liquid He temperatures. The results of the measurements are shown in Table 4. The temperature dependence of the specific heat is expressed as C = 234 R (770) + where R is the gas constant and 0 is the apparent Debye temperature. The authors concluded that the values of the specific heat coefficients and the Debye temperature are rather unusual (a low value of the apparent Debye temperature). They cannot be caused by... 

Bau] Baum, N.P., Schroder, K., Specific Heat of Chromium-Rich Chromium-Nickel and Chromium-Iron-Molybdenum Alloys Between 1.3 and 4.2 K , Phys. Rev. B Solid State, 3, 3847-3851 (1971) (Thermodyn., Experimental, 29)... 

The low temperature specific heat of ten ternary alloys with 3 at.% of Si have been investigated by [ 1977Si], the chromium content ranging from 0.049 to 0.97 at%. The Debye temperature was obtained by interpolation between the two limits of the soUd solution. 

Stainless steel is the designation for steel that has been made particularly corrosion proof by adding chromium Cr and nickel Ni. The table reference Engineering Materials Handbook specifies that austenitic stainless steel with 18 wt-% Cr and 8 wt-% Ni has a specific heat capacity c of 0.12 Btu/(°F lb). The unit 1 Btu ( British Thermal Unit ) = 1054 J and the unit 1 lb ( libra pound) = 0.454 kg. Calculate the mass-specific heat capacity c for the steel concerned using the SI unit kJ/kg K ... 

Example 3.3. Determine the lattice specific heat of chromium at 20 K as given by the Debye function. 

This is in good agreement with the specific heat of 6x 10cal/g K reported for chromium at 20 K in Table 3.4. 

Determine the specific heat of chromium at the normal boiling temperature of liquid hydrogen by use of the Debye function. 

Figure 12-8A. Piston rings. The piston rod is manufactured from heat-treated stainless steel and is coated with wear-resistant overlays, such as ceramic, chromium oxide, and tungsten carbide applied by plasma techniques. Piston rod cross-head attachment has mechanical preloading system for the threads. Rider rings and seal rings are manufactured from PTFE filled resins fillers are matched to the gas, piston speed, and liner specifications. Typical fillers are glass, carbon, coke, or ceramic. (Used by permission Bui. BCNA-3P100. Howden Process Compressors Incorporated. All rights reserved.)...

Stein et al. [673] have described a simplified, sensitive, and rapid method for determining low concentrations of cadmium, lead, and chromium in estuarine waters. To minimise matrix interferences, nitric acid and ammonium nitrate are added for cadmium and lead only nitric acid is added for chromium. Then 10,20, or 50 pi of the sample or standard (the amount depending on the sensitivity required) is injected into a heated graphite atomiser, and specific atomic absorbance is measured. Analyte concentrations are calculated from calibration curves for standard solutions in demineralised water for chromium, or an artificial seawater medium for lead and cadmium. 

Most of the pillared structures are thermally stable up to about 500°C, and keep the specific surface area as large as 300-500 m /g. The bismuth [11] and the chromium oxides pillared clays collapse on heating to 300°C, the pillars being removed out of the interlayer spaces, although the chromium oxide with a larger basal spacing of 21 A is more thermally stable in a nitrogen atmosphere [10]. 

A large fraction of the iron and steel produced today is recycled scrap. Since scrap does not require reduction, it can be melted down directly in an electric arc furnace, in which the charge is heated through its own electrical resistance to arcs struck from graphite electrodes above it. The main problem with this process is the presence of tramps (i.e., copper from electrical wiring, chromium, nickel, and various other metals) that accompany scrap steel such as crushed automobile bodies and that lead to brittleness in the product. Tin in combination with sulfur is the most troublesome tramp. Only the highest quality recycled steel—specifically, steel with no more than 0.13% tramps—can be used for new automobile bodies, and usually reprocessed scrap has to be mixed with new steel to meet these requirements. 

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