Diffusion treatment of quantum mechanics and its consequences

Localized ensemble of free microparticles spreads out as in a frictionless diffusion satisfying the principle of relativity. An ensemble of classical particles in a fluctuating classical scalar field diffuses in a similar way, and this analogy is used to formulate diffusion quantum mechanics (DQM). DQM reproduces quantum mechanics for homogeneous and gravity for inhomogeneous scalar field. Diffusion flux and probability density are related by Fick’s law, diffusion coefficient is constant and invariant. Hamiltonian includes a “thermal” energy, kinetic energies of drift and diffusion flux. The probability density and the action function of drift form a canonical pair and canonical equations for them lead to the Hamilton-Jacobi-Madelung and continuity equations. At canonical transformation to a complex probability amplitude they form a linear Schrödinger equation. DQM explains appearance of quantum statistics, rest energy (“thermal” energy) and gravity (“thermal” diffusion) and leads to a low mass mechanism for composite particles.

THERMODIFFUSION SATURATION OF THE SURFACE LAYERS OF α-TITANIUM BY OXYGEN, NITROGEN, CARBON

The purpose of the study is to analytically assess the depth of the gas-saturated zone in the case of a single-component diffusion saturation of alpha-titanium with nitrogen, oxygen and carbon from a rarefied controlled gas environment. Results. Based on the analysis of the literature data, the work schematically shows the interaction of alpha titanium with the elements of implementation and presents the processes with the corresponding parameters that characterize. It is shown that the surface impurity concentration is equal to the equilibrium concentration and is established instantly and does not depend on time. Consequently, with the proposed generalized nonstationary boundary condition in the absence of diffusion of impurities into the volume of the metal, the time dependence of its surface concentration is given, determined by the intensity of surface processes. The dependence of the relative change in the microhardness in the diffusion zone of titanium due to dissolved nitrogen (without taking into account the contribution of nitride inclusions) is presented. Analytically calculated concentration profiles of nitrogen generally correlate well with the distribution of the corresponding relative changes in microhardness in the surface layer. Analytical calculations of the concentration profiles of oxygen, nitrogen and carbon in titanium at a saturation temperature of 700 °C are presented. Practical value. The results obtained will make it possible to preliminarily estimate the size of the fortified near-surface layer depending on the parameters of chemical-thermal treatment and select the optimal parameters of thermal diffusion treatment to ensure the formation of reinforced layers on products made of alpha-titanium based on elements of interstitial in order to increase the functional properties.

Grain Boundary Diffusion Sources and Their Coating Methods for Nd-Fe-B Permanent Magnets

Nd-Fe-B magnets containing no heavy rare earth (HRE) elements exhibit insufficient coercivity to withstand the demagnetization field at elevated temperatures. The grain boundary diffusion (GBD) process provides the best route to fabricate high-coercive Nd-Fe-B magnets with low consumption of expensive HRE resources. Here we give a special review on the grain boundary diffusion sources and their coating methods. Up to now, various types of grain boundary sources have been developed, starting from the earliest Tb or Dy metal. The HRE-M eutectic alloys were firstly proposed for reducing the cost of the diffusion source. After that, the diffusion sources based on light rare earth and even non rare earth elements have also been proposed, leading to new understanding of GBD. Now, the diffusion sources including inorganic compounds, metals, and alloys have been employed in the industry. At the same time, to coat the diffusion source on the magnets before diffusion treatment, various methods have been developed. Different from the previous review articles for GBD, this review gives an introduction of typical types of diffusion sources and their fabrication approaches. The effects of diffusion source on the microstructure and magnetic properties are summarized briefly. In particular, the principles and applicability of different coating approaches were discussed in detail. It is believed that this review can provide a technical guidance for the industry for designing the diffusion process and products meeting specific requirements.

Effect of ultrasonic surface deep rolling combined with oxygen boost diffusion treatment on fatigue properties of pure titanium

Ultrasonic surface deep rolling (USDR), oxygen boost diffusion (OBD), and their combination (USDR-OBD) were all used to improve the surface hardening of pure titanium. The microstructure, microhardness, and fatigue life of pure titanium treated by USDR, OBD, and USDR-OBD methods were analyzed. USDR treatment induced a severe deformation area, while OBD treatment produced a brittle oxygen diffusion zone. The USDR-OBD treated samples approached the highest hardness in comparison with other treated samples. The fatigue lives of USDR treated samples were improved, which was due to the high compressive residual stress and refined grains. However, the fatigue lives of both OBD treated samples and USDR-OBD treated samples were decreased due to premature crack initiation and rapid propagation in the oxygen diffusion zone. Finally, the fatigue fracture mechanisms of different samples were proposed.

Effects of temperature on interfacial evolution and mechanical properties of pure titanium and carbon steel sheets bonded via new multi-pass continuous hot-roll diffusion with nickel interlayer

This study performed experiments and thermodynamic calculations to elucidate the effects of diffusion temperature on interfacial evolution and mechanical properties of pure titanium and carbon steel (i.e., steel) sheets bonded via a new type of multi-pass continuous hot-roll diffusion with nickel interlayer. The interfacial evolution results revealed that this new type of multi-pass continuous hot-roll diffusion treatment showed a very good adherence due to its metallurgy bonding, because it made a remarked improve to between compound and intermetallic compounds relationship. Secondly, in mechanical properties results revealed that the highest shear strength (∼470 MPa) was obtained at a processing temperature of 850°C. The highest peel strength (∼21 N/mm) was obtained in the sample processed at 900°C. Bonding temperatures above and below these levels reduced the bond strength respectively due to poor atom diffusion and excessive compound formation, resulting in joint failure at the Ti-Ni interface. Extensive cleavage planes with various alignments were observed on the fracture surfaces in these cases. Overall, a hot-rolling temperature of 850°C was found to provide the optimal tradeoff between interfacial bonding strength and ductility. This work provided an economical and convenient solution for broadening the engineering application of interface between sheets of pure titanium and steel.

Borate and Quaternary Ammonia Dip Diffusion to Treat Fungal Pathogens of Metrosideros polymorpha Wood

Rapid Ohia Death is a major concern for the viability of ohia (Metrosideros polymorpha) in Hawaii and has led to restrictions on log movement. The potential for using disodium octaborate tetrahydrate (DOT) and didecyl dimethyl ammonium chloride (DDAC) dip diffusion treatments to control the two causal fungi (Ceratocystis lukuohia and Ceratocystis huliohia) was investigated. A 10 percent boric acid equivalent dip diffusion treatment killed the pathogens in 0.5-cm-thick disks obtained from 4.0- to 5.0-cm-diameter limbs of naturally colonized trees. DOT tended to diffuse more consistently in 50- to 60-cm-long bolts of small (4.0 to 9.0 cm) and large (9.1 to 17.0 cm) diameter healthy ohia compared with those bolts naturally infected by C. lukuohia. Diffusion periods longer than 6 weeks resulted in deeper penetration. Immersion (24 h) of logs (1.3 m long; 9 to 17 cm diameter) from C. lukuohia artificially inoculated trees in two forest locations in a 15 percent DOT/1 percent DDAC solution and storage for 10 weeks before evaluation resulted in incomplete elimination of the pathogen and lower boron concentrations in the inner sapwood than outer. Further investigations are needed to explore using either higher boron concentrations or longer diffusion periods to deliver fungicidal concentrations of boron deeper within the wood matrix.