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Covetics by QED induced radiation
The QED enhanced yield strength of metal Covetics found by adding carbon particles to the melt during thermal processing depends on the particle size
By: QED Radiations
Covetics are new compounds thought formed by adding carbon to molten metals (aluminum, copper, silver, etc.) to produce carbon-metal bonds that enhance the yield strength of the metal. The history of Covetics is voluminous, but for a brief overview, see link  below, “Covetics - Rare new hybrid fuses nanocarbons and metal in bond stronger than sp2.”
However, controversy [2, 3] surrounds how the Covetics bond forms with the metal. During thermal processing of Covetics, a known amount of carbon is added to the molten metal. Upon solidification, Covetics samples are taken from which the carbon bonded to the metal is thought given by the difference between the carbon added and that combusted by the LECO method. LECO stands for Laboratory Equipment Corporation. In LECO, a sample is heated in oxygen to 1500 C and the carbon content inferred from the CO2 produced by the chemical reaction with oxygen by infrared absorption spectrometry.
But carbon bonding in Covetics is questionable as the density is observed [2, 4] not to change contrary to the law of mixtures that predicts ~10 % reduction in density. Moreover, the formation of the Covetics bond based on DFT studies  failed to show stable carbon-metal configurations. DFT stands for density functional theory.
Hence, the argument may be made that the Covetic melt does not produce bonds stronger than sp2 as it is energetically more favorable for the carbon particles to:
1. Remain as carbon particles in the lattice upon solidification,
2. Undergo combustion during: (a) thermal processing, and (b) LECO measurements of carbon content.
Central to this argument is how carbon added to the melt is combusted, i.e., as stated in :
“Unlike virtually all other forms of carbon and carbon compounds in metals, the nanocarbon in the covetics did not combine with oxygen at these temperatures. Instead, it remained in the melt, bound to the metal. We learned that we can, however, use the LECO method to detect carbon that is not in nanocarbon form.”
Particle Size and Quantum Mechanics
In Covetics, the carbon added to the melt during thermal processing may be nano or microcarbons. In Al Covetics , nanocarbons are 5-200 nm particles. In this PR, nanocarbons are referred to as NPs having sizes < 100 nm. NPs stands for nanoparticles. But in Cu Covetics , microcarbons comprising porous activated carbon 1-120 micron particles are added to the melt.
Unlike classical physics that allows the atom to always have heat capacity from the micro to the nanoscale, QM requires the heat capacity of the atom to vanish at the nanoscale. QM stands for quantum mechanics. For NPs, QM precludes the conservation of thermal energy acquired from the melt by an increase in temperature. Instead, NPs surprisingly remain at the temperature at which they are added to the molten metal, but microcarbons following classical physics do indeed increase in temperature. See diverse QED applications at http://www.nanoqed.org , 2009 – 2015
In Al Covetics , the NPs added to the melt at ambient temperature remain at ambient temperature during thermal processing and remain in the lattice upon solidification. Hence, the LECO method measures negligible CO2 produced as the chemical reaction of carbon NPs with oxygen occurs at ambient temperature, the consequence of which is carbon may be interpreted as bonded to the metal when in fact the carbon remains in the lattice as NPs.
By QM, NPs in the Al Covetic cannot conserve the heat from the melt by an increase in temperature. Instead, conservation proceeds by QED inducing the NPs under TIR confinement to emit EM radiation which for NPs is in the EUV. QED stands for quantum electrodynamics, TIR for total internal reflection, EM for electromagnetic, and EUV for extreme ultraviolet. Under EUV radiation, the Al atoms charge positive and undergo Coulomb repulsion. Hydrostatic tension is produced, the consequence of which is enhanced yield from the triaxial stress state that stiffens the Al lattice. The thumbnail depicts the Al lattice expected under hydrostatic tension away from the NPs. The QED induced stiffening mechanism was shown  in MD simulations to explain the increased yield strength of Ag above bulk observed in tensile tests of nanorods. MD stands for molecular dynamics.
The microcarbons  added to Cu Covetics do indeed acquire melt temperature and by combusting diminish in size to become NPs during thermal processing. Unlike the NPs added at ambient temperature, the NPs formed at melt temperature may not bond to Cu because it is energetically more favorable to simply undergo total combustion. Hence, NPs are not likely observed in Cu Covetics.
Microcarbons emit EM radiation in the far IR that lacking the Planck energy to ionize Cu atoms cannot enhance the yield of the Cu Covetic by QED stiffening. Whether carbon bonding increases the yield strength of Cu Covetics remains to be proven by tensile tests.
Covetics by QED radiation depends on whether the carbon added to the melt are NPs or microcarbons. Adding NPs at ambient temperature enhances the Covetics yield strength by QED stiffening of the lattice, but NPs remain in the lattice. In contrast, microcarbons acquire melt temperature and most likely are totally combusted, and therefore QED radiation lacking NPs cannot enhance the yield of the Covetics. For microcarbons, only carbon bonding may enhance the yield. Regardless, tensile tests are required to support claims of yield enhancement in Covetics.
The failure of DFT to find stable carbon-metal atomic binding configurations and the lower density expected from the law of mixtures is consistent with microcarbons added to the Covetics melt being totally combusted in thermal processing.
NPs are not observed in nanoscale Covetic films as the microcarbons added to the melt during thermal processing are most likely totally combusted.
 L. Luedke, “Covetics - Rare new hybrid fuses nanocarbons and metal in bond stronger than sp2,” at http://www.nanowerk.com/
 D. Forrest, et al., "Novel Metal Composites with integrally-bound nanoscale carbon," Nanotech 2012, Santa Clara, CA, 18 June 2012, CRC Press.
 L. Salamanca-Riba, et al., “A New Type of Carbon Nanostructure Formed Within a Metal-Matrix,”
 T. Knych, et al., “Characterization of Nanocarbon Copper Composites Manufactured in Metallurgical Synthesis Process,” Metal. Mat. Trans. B, March 14, 2014.
 L. Salamanca-Riba, “Advances’
 T. Prevenslik, “Quantum Mechanical Stiffening of Nanowires,” Proc. of the ASME 4th Micro/Nanoscale Heat & Mass Transfer Conf. MNHMT2013-22025, December 11-14, 2013, Hong Kong, China.
Page Updated Last on: Dec 29, 2014