The activation of magnetic nanoparticles (mNPs) by an alternating magnetic field (AMF) is currently being explored as technique for targeted therapeutic heating of tumors. Various types of superparamagnetic and ferromagnetic particles, with different coatings and targeting agents, allow for tumor site and type specificity. Magnetic nanoparticle hyperthermia is also being studied as an adjuvant to conventional chemotherapy and radiation therapy. This review provides an introduction to some of the relevant biology and materials science involved in the technical development and current and future use of mNP hyperthermia as clinical cancer therapy.

A systematic study of the effects of up to 1.1 at. % carbon on the mechanical properties and evolution of the dislocation substructure in a series of a high entropy alloys (HEA) based on Fe 40.4 Ni 11.3 Mn 34.8 Al 7.5 Cr 6 is presented. Transmission electron microscopy (TEM), synchrotron X-ray diffraction (XRD) and atom probe tomography (APT) were used to show that all the alloys are single-phase f.c.c. random solid solutions. The lattice constant, determined from synchrotron XRD measurements, increases linearly with increasing carbon concentration, which leads to a linear relationship between the yield strength and the carbon concentration. The dislocation substructures, as determined by a TEM, show a transition from wavy slip to planar slip and, at higher strains, and from cellforming structure (dislocations cells, cell blocks and dense dislocation walls) to non-cell forming structure (Taylor lattice, microbands and domain boundaries) with the addition of carbon, features related to the increase in lattice friction stress. The stacking fault energy (measured via weak-beam imaging of the separation of dislocation partials) decreases with increasing carbon content, which also contributes to the transition from wavy slip to planar slip. The formation of non-cell forming structure induced by carbon 3 leads to a high degree of strain hardening and a substantial increase in the ultimate tensile strength. The consequent postponement of necking due to the high strain hardening, along with the plasticity accommodation arising from the formation of microbands and domain boundaries, result in an increase of ductility due to the carbon addition.

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Only in the last few years has considerable progress been made in obtaining reproducible mechanical properties data for FeAl. Two sets of observations are the foundation of this progress. The frrst is that the large vacancy concentrations that exist in FeAl at high temperature are easily retained at low temperature and that these strongly affect the iowtemperature mechanical properties. The second is that room temperature ductiiity is adversely affected by the presence of water vapor. The purpose of this paper is not to present a comprehensive overview of the mechanical properties of FeAl but rather to highlight our understanding of key phenomena and to show how an understanding of the factors which control the yield strength and fracture behavior has followed from the discovery of the above two effects.In trod uc tion FeAl is a B2 or ordered body-centered-cubic compound that exists over a large compositional range, from 36.5 to 49.5 at. % A1 at room temperature, and up to a maximum temperature of Th Figure 1. The B2 structure adopted by FeAl, showing the slip vectors at low temperature, <111>, and high temperature, .1583 K (at 46 at. % Al) (1). Iron-rich-deviations from the stoichiometric composition are accommodated by Fe anti-site atoms. In addition, triple defects -two vacancies on the Fe sublattice site with an antisite (Fe) atom on the other (Al) sublattice -are present, especially in near-stoichiometric compositions (2). Irrespective of Fe:AI ratio, slip in FeAl occurs by the movement of anti-phase boundary (APB) coupled a/2<111> dislocations at low temperature but by the glide of perfect <100> dislocations at high temperature, see Figure 1. The temperature of this transition appears to decrease with increasing aluminum concentration (3-6). Slip occurs on { 112) or { 110) at low temperature but at room temperature and above slip is on { 110) (3,7-21).The summed manuscript has been authored by a WWaCtOr 960~464. Accordingly the U S. Government retains a nonexctusm royalty-free kmse to publish or reproduce the pubilshed foA of this ccntritpan. or allow others to do so, for U S. Government purposes of the U S Government under contract NO DE-ACOS-.t mechanical properties of FeAl were first reported as long ago as 1956 (22), but it is only in the last few years that progress has been made in obtaining reproducible mechanical data. Two sets of observations are the foundation of this recent progress. The first is that the large vacancy concentrations that exist in FeAl at high temperature are easily retained at low temperature (23) and that these strongly affect the lowtemperature mechanical properties (23-25), see Figure 2. The second is that room temperature ductility is reduced by water vapor (26).