Varying Boron Concentrations Research Articles

A genome-wide investigation of the mechanism underlying the effect of exogenous boron application on sugar content and overall quality of “Benihoppe” strawberries

In recent years, the widespread application of growth regulators and nutrients to boost yield and quality of strawberry fruits has led to the rapid growth of strawberry industry globally. Although the effects of major nutrients on strawberry yield have been widely studied, investigations into the effect of trace elements such as boron remain limited. This study examined the effect of boron application on the yield and quality of “Benihoppe” strawberry fruits. Nutrient solutions with varying boron concentrations (0, 0.024, 0.048, 0.072, and 0.096 mM) were applied to the plants, and their effect on fruit quality was evaluated. The results indicated that boron application enhanced the yield per plant, nutrient composition (total amino acid and vitamin C content), antioxidant properties (total phenol) and volatile components (esters) in strawberry fruits. Specifically, treatment with 0.048 mM boron concentration significantly increased the accumulation of soluble sugars, such as sucrose, whose concentration was 154.29% higher than that of the control treated with 0 mM concentration. This enhancement is attributable to the regulated expression of sucrose phosphate synthase (maker-Fvb2-2-augustus-gene-229.38) and β-fructofuranosidase-1/2/3 (augustus-masked-Fvb5-4-processed-gene-2.0, maker-Fvb5-3-augustus-gene-272.30, and maker-Fvb5-1-augustus-gene-0.37) genes, which play crucial roles in sugar metabolism and enzyme activity. Overall, boron application enhanced the quality of “Benihoppe” strawberries. The findings of this study offer substantial theoretical and practical guidance for using boron fertilizers in strawberry farming.

Low-Mineral Water Diminishes the Bone Benefits of Boron.

This study looked at how desalinated seawater, which has low minerals and high boron, could affect bone health. Prior research suggests that low mineral water may harm bone health and boron could be beneficial, but the overall impact on bone health is still unclear. Eighty-nine-week-old male Balb/C mice were allocated into eight groups and administered either tap water or purified water with varying boron concentrations (0, 5, 40, and 200 mg/L). They were kept in an environment mimicking tropical conditions (35-40 °C, 70-80% humidity) and underwent daily treadmill exercise for 13 weeks. At the 14th week, serum, femora, and lumbar vertebrae were collected for mineral metabolism, bone biomarker, microstructure, and biomechanics evaluation. Boron exposure improved bone formation, microstructure, and biomechanics initially but the benefits weakened with higher levels of exposure (p < 0.05). Co-exposure to purified water elevated serum boron but weakened the promotion of boron on bone minerals and the bone benefits of boron compared to tap water (p < 0.05). Thus, when studying the health effects of boron in desalinated seawater, it is crucial to look at various health effects beyond bone health. Furthermore, it is important to consider the mineral composition of drinking water when using boron for bone health benefits.

A compact scintillator-based detector with collimator and shielding for dose monitoring in boron neutron capture therapy

Boron neutron capture therapy exploits 10B(n,α)7Li reactions for targeted tumor destruction. In this work, we aimed at developing a dose monitoring system based on the detection of 478keV gamma rays emitted by the reactions, which is very challenging due to the severe background present. We investigated a compact gamma-ray detector with a pinhole collimator and shielding housing. Experimental nuclear reactor measurements involved varying boron concentrations and artificial shifts of the sources. The system successfully resolved the 478keV photopeak and detected 1cm lateral displacements, confirming its suitability for precise boron dose monitoring.

Insight of Oxidative Stress, Ultrastructural Transformations, and Elemental Variations in Rice Seedlings Exposed to Boron Toxicity: Unraveling the Role of Fe-SOD in Boron Tolerance

Rice (Oryza sativa L.) seedlings differing in boron tolerance were grown in hydroponics containing varying boron concentration. (as boric acid) for 8 days. Yoshida Nutrient Solution (Yoshida et al.1976) served as control, whereas 0.5 mM boron (moderately toxic) and 1.5 mM boron (highly toxic). Boron excess (B) caused marked reduction in length, biomass and relative water content of the seedlings, with more reductions in B-sensitive cv. Malaviya-36 as compared with B-tolerant cv. Brown Gora. B-sensitive seedlings showed higher B uptake in roots and shoots compared to the tolerant. Scanning electron microscopy (SEM) revealed ultrastructural damage to the guard cells with excess boron. Energy dispersive X-ray analysis (EDXA) of rice leaves showed decline in concentration of P, S, Ca and Mg in seedlings on B treatment. Increased production of reactive oxygen species O2˙−, H2O2, lipid peroxides, alteration in activity of antioxidative enzymes and increased membrane permeability was observed in B treated seedlings compared to controls. Real time PCR analysis of stress regulatory genes indicated differential expression of SOD isoforms in the two sets of cultivars with B treatment. Interestingly seedlings of B-tolerant cultivar were characterized by higher level of expression of Fe-SOD and its further increased expression on B treatment. Results suggest that B toxicity involves ultrastructural and elemental changes, increased generation of ROS and altered antioxidative enzyme activities in rice seedlings and increased expression Fe-SOD isoform appears to be associated with B tolerance.

High-energy-density metallized gel propellant by hydrogen-bonded polymer-small molecules for enhanced stability and shear-thinning performance

Metallized gel propellants with high metal content hold significant potential for enhancing the energy properties of hydrocarbon fuels. However, achieving an optimal balance between storage stability and atomization characteristics poses a significant challenge. In this study, we successfully synthesized metallized gel propellants that exhibit exceptional stability and remarkable shear-thinning properties by utilizing cooperative hydrogen bonding between polymer octanoyl cellulose and the small Thixatrol ST molecule. Through meticulous mixture design and formulation optimization, the metallized gel propellants demonstrated noteworthy characteristics, including a high calorific value of 48.48 MJ/kg, an impressive dynamic stability index of 89.12%, a surface tension of 23.21 mN/m, and sustained stability for at least six months under resting conditions. The metallized gel propellant, containing 50 wt% boron particles, exhibited a density 1.54 times higher than pure kerosene, meeting the requirements for enhancing specific impulse in rocket and ramjet engines. Moreover, optimized samples with varying boron concentrations were evaluated for their rheological properties and atomization behavior. The results revealed that the inclusion of boron particles increased the viscosity of the metallized gels. Consequently, the sample with 50 wt% boron exhibited modified viscosity-flow behavior, resulting in the formation of larger gel droplets during atomization. Finally, the metallized gel propellant demonstrated successful ignition in ramjet engine experiments. We anticipate that the cooperative hydrogen bonding between the polymer and small molecule will pave the way for the development of high-content metallized gel propellants with exceptional stability and superior shear thinning performance.

Boron-doped amorphous carbon deposited by DC sputtering for a hardmask: Microstructure and dry etching properties

Boron-doped amorphous carbon (a-C) films have been investigated as a hardmask material for improving semiconductor integration, deposited using direct current (DC) magnetron sputtering with varying boron concentrations. Increased boron doping concentration in a-C led to a higher etch resistance but also resulted in the gradation of etch resistivity in the depth direction of the film, as confirmed by a continuous dry etching process. Scanning transmission electron microscopy electron energy loss spectroscopy showed an increase in the sp3 ratio of the film owing to boron doping as well as gradation in the B K edge region of a film doped with a high concentration of boron. This is because the high reactivity between boron and oxygen results in the reaction of residual oxygen in the chamber with boron. Time-of-flight secondary ion mass spectrometry was used to evaluate the penetration resistance to fluorine ions in the dielectric etchant. The results confirmed that B-O bonding resulted in relatively low fluorine resistance. Boron bonded with carbon can significantly improve the dry etch performance; however, bonding with oxygen needs to be effectively controlled to realize desirable film properties. Overall, this study demonstrates the potential of boron-doped a-C films as a hardmask material for the semiconductor industry.

Energy production from treatment of industrial wastewater and boron removal in aqueous solutions using microbial desalination cell

As a result of a much needed paradigm shift worldwide, treated saline water is being considered as a viable option for replacing freshwater resources in agricultural irrigation. Vastly produced geothermal brine in Turkey may pose a significant environmental risk due to its high ionic strength, specifically due to boron. Boron species, which are generally found uncharged in natural waters, are costly to remove using high-throughput membrane technologies such as reverse osmosis. Recent advances in bioelectrochemical systems (BES) has facilitated development of energetically self-sufficient wastewater treatment and desalination. In this study, removal of boron from synthetic solutions and real geothermal waters, along with simultaneous energy production, using the microbial desalination cell (MDC) were investigated. Optimization studies were conducted by varying boron concentrations (5, 10, and 20 mg L−1), air flow rates (0, 1, and 2 L min−1), electrode areas (18, 24, 36, and 72 cm2), catholyte solutions, and operating modes. Even though the highest concentration decrease was observed for 20 mg-B L−1, 5 mg-B L−1 concentration experiment gave the closest result to the 2.4 mg-B L−1 limit value asserted by WHO. Effect of electrode surface area was proven to be significant on boron removal efficiency. Employing the optimum conditions acquired with synthetic solutions, boron and COD removal efficiencies from real geothermal brine were 44.3% and 90.6%, respectively. MDC, being in its early levels of technology readiness, produced promising desalination and energy production results in removal of boron from geothermal brine.

Effect of Boron on Pollen Attributes in Different Cultivars of Malus domestica L.

The effect of varying boron concentrations on in vivo pollen germination and tube penetration in four different apple cultivar crosses among ‘Golden Delicious,’ ‘Red Delicious,’ ‘Gala’ and ‘Fuji’ was evaluated. Boric acid (H3BO3) with two different concentrations: 1000 and 2000 mg L−1, was sprayed on the foliage long before the onset of flowering. Pollen–pistil interaction vis-a-vis pollen germination and tube penetration was evaluated using fluorescence microscopy technique, 72 and 120 h after manual pollination. Among different crosses, ♀Golden delicious × Red delicious♂ treated at 1000 mg L−1 concentration of boric acid showed maximum (27.39%) pollen germination and pollen tubes at different levels inside the style. In control without boron, only 6.49% germination was observed. Interaction of boron conc. × time depicted maximum pollen germination and tube number 120 hap. The present study demonstrates that foliar application of boron beyond 1000 mg L−1 on different apple cultivars reduces germination of pollen and development of pollen tubes down the style.

Influence of boron doping on the structural, spectral, optical and morphological properties of TiO2 nanoparticles synthesized by sol–gel technique for DSSC applications

In the present work, boron-doped TiO2 nanoparticles are synthesized by sol–gel technique with varying boron concentrations (0.025–0.3 M). The X-ray diffraction pattern shows the tetragonal crystal structure with the anatase phase. The average crystallite size is found to be decreased from 11.83 to 6.14 nm with increasing the boron concentration. The peak observed at 1372 cm−1 from FTIR confirms the presence of Ti – O – B vibrations. UV-DRS analysis shows the absorption edge is blue-shifted due to the incorporation of boron and the bandgap values increases from 2.95 to 3.17 eV. From PL analysis, the variation of emission edge and intensity of boron doped TiO2 nanoparticles is attributed to the subsequent doping with host lattices. The surface morphology of the synthesized particle is spherical in shape with agglomeration. DSSCs fabricated using pristine (undoped) TiO2, BT3 and BT4 photoanodes show the efficiency of 2.28%, 3.91% and 3.37%.

Quantification of history effects in PWR modelling

Nowadays, the application of nodal methods and cross section homogenization is a standard practice in reactor core design and safety studies. Specifically, nodal cross sections are prepared with the planned physical operating conditions in the single fuel assemblies, thus assuming different approximations like for instance a constant exposure at nominal power. Concerning the light water reactors, this scheme was especially suitable for the first PWR units operating on base load, and much less for BWRs due to the strong core heterogeneities and strong axial water density variation which required ad hoc corrections. The new generation of PWRs and yet the current units in Europe show frequent use of control rod elements in order to operate on load-following. In general, the current few group cross section models of core simulators are not designed to cover very long periods of control bank insertions, thus arising the problem of the physical representation. In this work, we quantify the errors on nodal cross sections in presence of strong insertion of control rods, using the classical approach for the cross sections preparation based on a single PWR assembly homogenization. The framework of the Burn-up Credit Criticality Benchmark NEA-6227 (Phase II-D) is used to model different rodded configurations of a UO2 fuel assembly by the lattice code APOLLO2.8, providing also additional validation elements for the code. Different insertion patterns along the multiple core cycles are investigated and differences against the standard cross section generation, which considers the control rods insertion only as a perturbation along the exposure in the nominal depletion sequence, are studied. Still using the framework of this benchmark, other test cases are formulated to investigate the influence of varying boron concentration along the fuel cycles, different water densities and the aging of control elements. In particular, the latter is marked as potential issue when staging a very long insertion as with the main cases of the benchmark. We also discuss mesh refinement to model “the skin effect” when depleting the absorption materials of control rods. The suggestions for the improved modelling are given in the conclusion.

Pseudoelasticity in Fe3Ga with boron-A combined atomistic–micromechanical treatment

The Fe3Ga base alloy is known to exhibit pseudoelasticity and the solute hardened Fe3GaB holds considerable promise as well. The present work aims at developing a theoretical model to establish the critical twinning stress in Fe3Ga with varying boron concentration. The theoretical model is based on the atomistic–micromechanical approach where we utilize density functional theory and Peierls Nabarro formalism at an atomic scale and the Eshelbian anisotropic elasticity at microscale. Using local strain measurements at the grain scale, we also show the experimental evidence of effect of boron in elevating the twinning stress in Fe3Ga. The work calculates the interaction energies associated with the presence of boron in octahedral, tetrahedral and xenohedral sites in the D03 lattice and the transition from octahedral to xenohedral sites upon twinning. The model distinguishes the elevation of twinning stress depending on the interstitial site and the transition between the sites.

Surface Roughness and Critical Exponent Analyses of Boron-Doped Diamond Films Using Atomic Force Microscopy Imaging: Application of Autocorrelation and Power Spectral Density Functions

The evolution of the surface roughness of growing metal or semiconductor thin films provides much needed information about their growth kinetics and corresponding mechanism. While some systems show stages of nucleation, coalescence, and growth, others exhibit varying microstructures for different process conditions. In view of these classifications, we report herein detailed analyses based on atomic force microscopy (AFM) characterization to extract the surface roughness and growth kinetics exponents of relatively low boron-doped diamond (BDD) films by utilizing the analytical power spectral density (PSD) and autocorrelation function (ACF) as mathematical tools. The machining industry has applied PSD for a number of years for tool design and analysis of wear and machined surface quality. Herein, we present similar analyses at the mesoscale to study the surface morphology as well as quality of BDD films grown using the microwave plasma-assisted chemical vapor deposition technique. PSD spectra as a function of boron concentration (in gaseous phase) are compared with those for samples grown without boron. We find that relatively higher boron concentration yields higher amplitudes of the longer-wavelength power spectral lines, with amplitudes decreasing in an exponential or power-law fashion towards shorter wavelengths, determining the roughness exponent (α ≈ 0.16 ± 0.03) and growth exponent (β ≈ 0.54), albeit indirectly. A unique application of the ACF, which is widely used in signal processing, was also applied to one-dimensional or line analyses (i.e., along the x- and y-axes) of AFM images, revealing surface topology datasets with varying boron concentration. Here, the ACF was used to cancel random surface “noise” and identify any spatial periodicity via repetitive ACF peaks or spatially correlated noise. Periodicity at shorter spatial wavelengths was observed for no doping and low doping levels, while smaller correlations were observed for relatively higher boron concentration. These semiquantitative spatial analyses may prove useful in comparing synthesis techniques and varying compositional makeups of diamond films and other technologically important electronic materials. These findings in terms of critical exponents are also correlated with traditional Raman spectroscopy and x-ray diffraction structural properties, thus helping to provide insight into the growth kinetics, albeit in reverse manner.

The Lattice Kinetic Monte Carlo Simulation of Boron Diffusion in SiGe

The lattice kinetic Monte Carlo simulation (kMCS) was applied to study the boron diffusion in Si-SiGe beyond nanotechnology. Both the interstitialcy and kick-out mechanisms of boron diffusion were considered, including the effects of annealing temperatures, boron dopant concentrations, Ge compositions, and concentrations of Si self-interstitial defects (SiI). The effects on boron diffusion caused by single and double layer(s) of SiGe phase with different Ge contents and varying boron concentrations in double layers of SiGe phase were also simulated. The results show that boron diffusion in Si and between SiGe-Si both largely increase as the temperature or concentration of SiI increases, but the boron diffusion between SiGe-Si is much less than in Si. Increasing the Ge contents in SiGe alloy could retard boron diffusion heavily, while increasing the boron concentration on SiGe phase would enhance boron diffusion.

Borate as a Synergistic Anion for Marinobacter algicola Ferric Binding Protein, FbpA: A Role for Boron in Iron Transport in Marine Life

Boron in the ocean is generally considered a nonbiological element due to its relatively high concentration (0.4 mM) and depth independent concentration profile. Here we report an unexpected role for boron in the iron transport system of the marine bacterium Marinobacter algicola. Proteome analysis under varying boron concentrations revealed that the periplasmic ferric binding protein (Mb-FbpA) was among the proteins whose expression was most affected, strongly implicating the involvement of boron in iron utilization. Here we show that boron facilitates Fe(3+) sequestration by Mb-FbpA at pH 8 (oceanic pH) by acting as a synergistic anion (B(OH)4(1-)). Fe(3+) sequestration does not occur at pH 6.5 where boric acid (B(OH)3; pK(a) = 8.55) is the predominant species. Borate anion is also shown to bind to apo-Mb-FbpA with mM affinity at pH 8, consistent with the biological relevance implied from boron's oceanic concentration (0.4 mM). Borate is among those synergistic anions tested which support the strongest Fe(3+) binding to Mb-FbpA, where the range of anion dependent affinity constants is log K'(eff) = 21-22. Since the pKa of boric acid (8.55) lies near the pH of ocean water, changes in oceanic pH, as a consequence of fluctuations in atmospheric CO2, may perturb iron uptake in many marine heterotrophic bacteria due to a decrease in oceanic borate anion concentration.

Characterization and oxidation behavior of MTCVD Ti–B–N coatings

In this work, Ti–B–N coatings have been prepared by moderate temperature chemical vapor deposition (MTCVD). The effect of a varying boron concentrations (9.6 and 55.4at.%) on the chemical composition and the oxidation behavior was investigated by XRD, SEM, WDS, XPS and Raman spectroscopy. The results clearly demonstrate a good correlation between the different techniques. The same transition trends were observed in the examined Ti–B–N system in the progression from TiN to TiB2 by the addition of boron. At boron concentrations ≥18at.%, the coatings reveal a two phase structure comprising a nanocrystalline TiN phase embedded in an amorphous TiB2 matrix. In Ti–B–N coatings with boron concentrations ≤18at.%, the high sensitivity of Raman spectroscopy enabled the identification of an amorphous TiB phase.The oxidation behavior of Ti–B–N coatings was found to be affected by the boron concentration as well. Boron concentrations ≤18at.% improve the thermal stability compared to TiN, most likely due to the TiB phase present in these coatings. Ti–B–N coatings with a high boron concentration show a higher degree of oxidation compared to TiN manifested in a higher oxide layer thickness. In addition, these coatings tend to form boron oxides on their surface, which lead to the formation of metastable anatase rather than the thermodynamically stable rutile.

Boron in Human Health: Evidence for Dietary Recommendations and Public Policies

For over twenty years boron has been of interest to investigators confirming the safety and essentiality of the element in humans. Fruits, vegetables, nuts, and pulses are natural sources of boron in the diet which world wide averages about 1-3 mg daily for most adults. In boron-rich regions of Turkey drinking water sources with 29 mg boron/liter are consumed without harmful effects. The European Union established a safe drinking water standard of 1.0 mg boron/ litre a level difficult for some regions to achieve. Safe standards are difficult to establish due to limited information and widely varying boron concentrations in food and water, high exposures in boron-rich regions or occupational settings and voluntary intakes, for example, of boron containing products. Current research implicates boron as an essential nutrient in humans demonstrating healthful effects in cellular functions associated with osteoporosis, arthritis, inflammation and cancer. Proposed mechanisms of action implicate that boron, found in cells as boric acid, participates in important membrane functions and intracellular signaling cascades. Traditionally, biochemical mechanisms associated with health- fully beneficial effects are needed for nutrients to meet the criteria for essentiality in humans. While boron meets the traditional criteria to be determined essential in humans the research process has provided additional insight into essential- ity for boron insight that essentiality for trace elements may based on different criteria. The study of boron in living systems provides a more fundamentally important role by demonstrating functions for trace elements differing from those needed to confirm essentiality previously for carbon based compounds, i.e., carbohydrates, lipids, proteins, and vitamins in human nutrition. To conclude, boron can be a model element to introduce a new field of study, elementomics. Further studies from boron-rich areas are needed to determine essentiality, dietary requirements, metabolic functions, therapeutic applications, economic benefits and important public policies for boron, a biologically important trace element.

The effect of boron on the abrasive wear behavior of austenitic Fe-based hardfacing alloys

The effect of boron on the abrasive wear behavior of the austenitic Fe–Cr–C–Si–B hardfacing alloys was investigated with varying boron concentration. It was found that the abrasive wear resistance of the hardfacing alloys increased up to 50% compared to that of boron-free alloys with increasing boron concentration. The mechanism of the abrasive wear resistance changed at 0.6wt.% boron. Below 0.6wt.% boron concentration, the abrasive wear resistance was improved almost linearly and strain-induced martensitic transformation was considered as the controlling factor for improving the resistance. Above 0.6wt.% boron, it was observed that the primary borides started to precipitate. Further increase in boron concentration was not able to enhance the resistance due to the negligible change of primary borides’ size and volume fraction. With these results, it was concluded that two different effects of boron on the wear resistance of the austenitic Fe–Cr–C–Si–B hardfacing alloys existed depending on the boron concentration.

The effect of boron doping and gamma irradiation on the structure and properties of microwave chemical vapor deposited boron-doped diamond films

We investigated the effects of gamma irradiation doses of 50, 100, and 103 kGy on boron-doped diamond (BDD) thin films synthesized using microwave plasma-assisted chemical vapor deposition with varying boron concentrations of [B]/[C]gas = 100, 1000, 2000, and 4000 ppm. The diamond thin films were characterized prior to and post-irradiation and the influence was assessed in terms of morphology, structure, and physical properties using scanning electron microscopy, atomic force microscopy, x-ray diffraction, vibrational spectroscopy (Raman and IR), x-ray photoelectron spectroscopy, and electrical measurement techniques. The results clearly showed that the response of gamma irradiation on BDD films was distinctive compared to those of undoped diamond films with changes in electronic behavior from metallic (&gt;1019 to 1020 cm–3) to semiconducting (≤1019 cm–3), especially in the case of heavily boron-doped diamond films demonstrated by micro-Raman spectroscopy and electrical property characteristics. In fact, this modification in electrical property behavior induced by “gamma conditioning” can be effectively used to fine control boron doping in chemically vapor deposited diamond much needed for various electronic devices. The “gamma conditioning” refers to material processing by radiation which helps to passivate electrically active boron and defects with hydrogen migration thus fine tunes the boron acceptor concentration albeit that this is difficult to achieve during BDD film deposition. In addition, the results also indicate that almost all of the BDD films studied hereby tend to reach a state of damage saturation when submitted to gamma irradiation of 103 kGy. We discuss our novel findings in terms of the interplay of boron-hydrogen in diamond with possible multiple scenarios: (i) the generation of point/Frenkel defects due to Compton scattered electrons, (ii) the formation of a nonmetallic boron-rich borocarbide (e.g., B13C2) phase, (iii) the passivation of electrically active acceptor (B) sites due to the invariable presence of H in the grains and at the grain boundaries, (iv) the desorption of H from the diamond surface, and (v) the “priming or pumping” effect, which improves the electronic properties by compensating for the shallow boron acceptors to produce semiconducting/insulating material, verified by the cold neutron depth profiling technique.

Machining of Difficult-to-Cut Materials with a Lubricant Coated Tool

Tools coated with TiBON films of varying boron concentrations were made, and the influence of boron concentration on tool wear was investigated. The TiBON coating film acts as a lubricant at high temperature. Tools coated with such films were applied to the machining of difficult-to-cut materials (Ti-6Al-4V and Inconel 718), where the cutting temperature increases rapidly and heavy adhesion occurs. In the experiment, turning and interrupted cutting were performed. In cutting of Ti-6Al-4V, the tool coated with a film of high boron concentration showed long tool life. In turning of Inconel 718, the tool coated with a film of a boron concentration of 15% showed the longest tool life-about four times longer than that of a tool coated with TiAlN.

Machining of Difficult-to-Cut Materials with a Lubricant Coated Tool

Tools coated with TiBON films of varying boron concentrations were made, and the influence of boron concentration on tool wear was investigated. The TiBON coating film acts as a lubricant at high temperature. Tools coated with such films were applied to the machining of difficult-to-cut materials (Ti-6Al-4V and Inconel 718), where the cutting temperature increases rapidly and heavy adhesion occurs. In the experiment, turning and interrupted cutting were performed. In cutting of Ti-6Al-4V, the tool coated with a film of high boron concentration showed long tool life. In turning of Inconel 718, the tool coated with a film of a boron concentration of 15% showed the longest tool life-about four times longer than that of a tool coated with TiAlN.