THE SPECIFIC HEAT OF COPPER FROM 20° TO 300 deg;K

1960 ◽  
Vol 38 (1) ◽  
pp. 17-24 ◽  
Author(s):  
Douglas L. Martin
Keyword(s):  
Specific Heat ◽  
Pure Copper ◽  
Annealed Sample ◽  
Rolled Material ◽  
Temperature Range ◽  
Specific Heats ◽  
Commercially Pure ◽  
Cold Rolled ◽  
Cold Worked ◽  
Annealed Copper

The specific heats of commercially pure cold-rolled copper and of annealed and heavily cold-worked 99.999% pure copper have been measured in the temperature range 20° to 300 deg;K. When results are averaged over the whole temperature range of measurement the specific heat of the pure cold-worked copper is about 0.15% above that of the pure annealed sample while results for the commercially pure cold-rolled material lie in an intermediate position. Results on a given sample are reproducible within 0.05%. The entropy of pure annealed copper at 298.15 deg;K is 7.92 ± 0.04 cal/°K g-atom.

Specific heats of polymer powders by differential scanning calorimetry

1982 ◽  
Vol 60 (14) ◽  
pp. 1853-1856 ◽  
Author(s):  
Eva I. Vargha-Butler ◽  
A. Wilhelm Neumann ◽  
Hassan A. Hamza
Keyword(s):  
Differential Scanning Calorimetry ◽  
Specific Heat ◽  
Scanning Calorimetry ◽  
Temperature Range ◽  
Specific Heats ◽  
Powdered Form ◽  
Polymer Powders

The specific heats of five polymers were determined by differential scanning calorimetry (DSC) in the temperature range of 300 to 360 K. The measurements were performed with polymers in the form of films, powders, and granules to clarify whether or not DSC specific heat values are dependent on the diminution of the sample. It was found that the specific heats for the bulk and powdered form of the polymer samples are indistinguishable within the error limits, justifying the determination of specific heats of powders by means of DSC.

An anomaly in the specific heat below 3 °K of copper containing hydrogen

1969 ◽  
Vol 47 (14) ◽  
pp. 1485-1491 ◽  
Author(s):  
Neil Waterhouse
Keyword(s):  
Specific Heat ◽  
Molecular Hydrogen ◽  
Pure Copper ◽  
Solid Hydrogen ◽  
Rotational State ◽  
Experimental Results ◽  
Ortho Hydrogen ◽  
Temperature Range ◽  
A Value ◽  
Heat Curve

The specific heat of copper heated in hydrogen at 1040 °C has been measured over the temperature range 0.4 to 3.0 °K and found to be anomalous. The anomaly occurs in the same temperature range as the solid hydrogen λ anomaly which, in conjunction with evidence of ortho to para conversion of hydrogen in the sample, suggests the presence of molecular hydrogen in the copper. The anomaly reported by Martin for "as-received" American Smelting and Refining Company (ASARCO) 99.999+ % pure copper has been briefly compared with the present results. The form of the anomaly produced by the copper-hydrogen specimen has been compared with Schottky curves using the simplest possible model, that for two level splitting of the degenerate J = 1 rotational state of the ortho-hydrogen molecule.Maintenance of the copper-hydrogen sample at ~20 °K for approximately 1 week removed the "hump" in the specific heat curve. An equation of the form Cp = γT + (464.34/(θ0c)3)T3 was found to fit these experimental results and produced a value for γ which had increased over that for vacuumannealed pure copper by ~2%.

FIRST SOUND IN LIQUID HELIUM AT HIGH PRESSURES

1953 ◽  
Vol 31 (7) ◽  
pp. 1156-1164 ◽  
Author(s):  
K. R. Atkins ◽  
R. A. Stasior
Keyword(s):  
Specific Heat ◽  
Liquid Helium ◽  
Carrier Frequency ◽  
High Pressures ◽  
Constant Pressure ◽  
Constant Density ◽  
Pulse Technique ◽  
Temperature Range ◽  
Specific Heats ◽  
First Sound

The velocity of ordinary sound in liquid helium has been measured in the temperature range from 1.2 °K. to 4.2 °K. at pressures up to 69 atm. A pulse technique was used with a carrier frequency of 12 Mc.p.s. Curves are given for the variation of velocity with temperature at constant pressure and also at constant density. There is no detectable discontinuity along the λ-curve. The results are used to discuss the ratio of the specific heats, the coefficient of expansion below 0.6 °K., and the specific heat above 3 °K.

Specific heats of plutonium and neptunium

1970 ◽  
Vol 317 (1530) ◽  
pp. 303-317 ◽  
Keyword(s):  
Specific Heat ◽  
Smooth Function ◽  
Magnetic Ordering ◽  
Temperature Range ◽  
Specific Heats ◽  
Very High

The specific heats of plutonium and neptunium metal have been measured from 13 and 7.5 K respectively, to 300 K. Both metals have very high electronic specific heats of 15.9 and 14.2 mJ mol -1 K -2 . A small anomaly in plutonium at about 60 K was found and is possibly caused by magnetic ordering. The specific heat of neptunium is a smooth function over the whole temperature range.

scholarly journals An Investigation on Dislocation Density in Cold-Rolled Copper Using Electrochemical Impedance Spectroscopy

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Elyas Rafiee ◽  
Mansour Farzam ◽  
Mohammad Ali Golozar ◽  
Ali Ashrafi
Keyword(s):  
Charge Transfer ◽  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Dislocation Density ◽  
Electrochemical Impedance ◽  
Pure Copper ◽  
Annealed Sample ◽  
Charge Transfer Resistance ◽  
Transfer Resistance ◽  
Cold Rolled

Variation of electrochemical impedance with dislocation density was investigated using electrochemical impedance spectroscopy (EIS). For this purpose, EIS measurements were carried out on 10, 20, 30, 40, and 50% cold-rolled commercially pure copper in 0.1 M NaCl (pH = 2) solution. Nyquist plots illustrated that the electrochemical reactions are controlled by both charge transfer and diffusion process. Increasing dislocation density, the magnitude of electrochemical impedance of samples was decreased. Decreasing magnitude of impedance at intermediate frequencies indicated increasing double-layer capacitance. Charge transfer resistance decreased from value 329.6 Ωcm2 for annealed sample to 186.3 Ωcm2 for sample with maximum dislocation density (1.72×1015 m−2). Phase angles were lower for samples that contained more dislocation density, indicating more tendencies to loss of electrons and releasing atoms into electrolyte.

Mechanical Properties of Some Cold-Rolled Plastics

1967 ◽  
Vol 9 (5) ◽  
pp. 362-369 ◽  
Author(s):  
J. G. Williams ◽  
Hugh Ford
Keyword(s):  
Mechanical Properties ◽  
Cold Rolling ◽  
Compression Tests ◽  
Stress Strain ◽  
Material Density ◽  
Rolled Material ◽  
General Improvement ◽  
Cold Rolled ◽  
Cold Worked

A technique for cold rolling thermoplastics is described and the results of compression tests on some rolled materials are described in terms of basic stress-strain curves. There is evidence of a general improvement in mechananical performance particularly for biaxially oriented (cross-rolled) material. Density changes are examined and a pronounced resistance to environmental cracking for cold-worked materials is reported.

The specific heat of pure copper and of some dilute copper + iron alloys showing a minimum in the electrical resistance at low temperatures

1961 ◽  
Vol 263 (1315) ◽  
pp. 494-507 ◽  
Keyword(s):  
Specific Heat ◽  
Electrical Resistance ◽  
Low Temperatures ◽  
Pure Copper ◽  
Iron Alloys ◽  
Absolute Zero ◽  
Iron Ions ◽  
Temperature Range ◽  
Dilute Alloys ◽  
Resistance Minimum

The specific heat of pure copper and of some dilute alloys of iron in copper, containing approximately 0.05, 0.1 and 0.2at. % iron, have been measured in the temperature range 0.4 to 30 °K. The electrical resistance of the copper + iron alloys has been measured from 0.4 to 80 °K. The alloys show specific-heat anomalies which probably extend from the absolute zero of temperature to the region of the minimum in electrical resistance. The entropy contents of the anomalies lie close to the value R In 2 per mole of iron suggesting that only two energy states of the iron ions are involved in the resistance minimum phenomena. The results are discussed in relation to existing theories.

Ti-3Al-2.5V

Alloy Digest ◽  
1990 ◽  
Vol 39 (4) ◽  
Keyword(s):  
Corrosion Resistance ◽  
Titanium Alloy ◽  
Physical Properties ◽  
Tensile Properties ◽  
Elevated Temperatures ◽  
Heat Treating ◽  
Commercially Pure ◽  
Pure Grade ◽  
Alpha Titanium ◽  
Cold Worked

Abstract Ti-3A1-2.5V is a near-alpha titanium alloy offering 20-50% higher tensile properties than the strongest commercially pure grade of titanium at both room and elevated temperatures. Normally furnished in the annealed, or in the cold-worked stress-relieved condition, Ti-3A1-2.5V titanium alloy features excellent cold formability and good notch tensile properties, as well as corrosion resistance in many environments. This datasheet provides information on composition, physical properties, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Ti-95. Producer or source: Titanium alloy mills.

An EBSD Study on Orientation Effects during Recrystallization of Coarse-Grained Niobium

2004 ◽  
Vol 467-470 ◽  
pp. 519-524 ◽  
Author(s):  
Hugo Ricardo Zschommler Sandim ◽  
Dierk Raabe
Keyword(s):  
Longitudinal Section ◽  
Primary Recrystallization ◽  
Coarse Grained ◽  
Subgrain Structure ◽  
Electron Backscattered Diffraction ◽  
Subgrain Growth ◽  
Metallographic Inspection ◽  
Cold Rolled ◽  
Cold Worked ◽  
Viable Mechanism

The recrystallization behavior of coarse-grained niobium depends on the nature of its deformation microstructure. In this regard, a longitudinal section of a high-purity coarse-grained niobium ingot was cold rolled to a thickness reduction of 96% followed by annealing in vacuum at 800°C for 1 h. Metallographic inspection in cold-rolled and annealed specimens was carried out in a field emission gun scanning electron microscope (FEG-SEM). Microtexture was determined by electron-backscattered diffraction (EBSD) coupled to the FEG-SEM. The use this technique has evidenced details of the boundary character and subgrain structure found in partially recrystallized regions. The early stages of primary recrystallization are associated to the presence of high-angle lamellar boundaries found in the cold-worked state. Abnormal subgrain growth has been evidenced as a viable mechanism for nucleation of recrystallization.

Effects of Macroscopic Pores on the Damping Behaviors of Metal Materials

2011 ◽  
Vol 66-68 ◽  
pp. 1155-1162
Author(s):  
Jian Ning Wei ◽  
Gen Mei Li ◽  
Li Ling Zhou ◽  
Xue Yun Zhou ◽  
Jian Min Yu ◽  
...  
Keyword(s):  
Internal Friction ◽  
Pure Aluminum ◽  
Air Pressure ◽  
Damping Capacity ◽  
Infiltration Process ◽  
Pressure Infiltration ◽  
Temperature Range ◽  
Commercially Pure ◽  
Damping Behavior ◽  
Metal Materials

A large number of macroscopic pores were introduced into commercially pure aluminum (Al) and Zn-Al eutectoid alloy by air pressure infiltration process to comparatively study the influence of macroscopic pores on the damping behaviors of the materials. Macroscopic pores size are on the order of a millimetre (0.5~1.4mm) and in large proportions, typically high 76vol.%. The damping behavior of the materials is characterized by internal friction (IF). The IF was measured on a multifunction internal friction apparatus (MFIFA) at frequencies of 0.5, 1.0 and 3.0 Hz over the temperature range of 25 to 400 °C, while continuously changing temperature. The damping capacity of the metal materials is shown to increase with introducing macroscopic pores. Finally, the operative damping mechanisms in the metal materials with macroscopic pores were discussed in light of IF measurements.

Sign in / Sign up

Export Citation Format

Share Document