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Massive data growth is accelerating the need for storage. Hard Disk Drive read/write technology continues to advance to support this demand. This Advanced Storage Research Consortium report combines a top-down (system) and bottom-up (micromagnetic) approach to define a reader technology roadmap for 2.4, 4.0 and 6.0 Tbpsi including dimensional and performance targets. We examine the resolution, SNR, stability and manufacturing requirements, challenges, and gaps. We show that the extension of today’s Spin Valve-based reader designs may enable 4Tbpsi, but significant gaps must be closed. For higher Areal Densities, we review future reader designs, challenges, and discuss potential solution paths.

The ballistic performance, and behaviour, of an armour system is governed by two major sets of variables, geometrical and material. Of these, the consistency of performance, especially against small arms ammunition, will depend upon the consistency of the properties of the constituent materials. In a body armour system for example, fibre diameter, areal density of woven fabric, and bulk density of ceramic are examples of critical parameters and monitoring such parameters will form the backbone of associated quality control procedures. What is often overlooked, because it can fall into the User’s domain, are the interfaces that exist between the various products; the carrier, the Soft Armour Insert (SAI), and the one or two hard armour plates (HAP1 and HAP2). This is especially true if the various products are sourced from different suppliers. There are between 30 and 150 individual layers within a typical body armour system, and each of the interfaces between each of those layers will, in some way or another, contribute to the ballistic performance of the system. For example, consider the following interfaces/interlayers: (i) the frictional, sliding, inter-ply surfaces within a soft armour pack, and also between the pack and the carrier, (ii) the air-gaps that may develop within the soft armour pack, (iii) the interconnecting space between the soft armour pack and the hard armour plate, (iv) the nature of the interfaces between adjacent plies of a multiplied backing laminate, even in a highly compressed Ultra High Molecular Weight Polyethylene (UHMWPE) variant, (v) the interlayer between the ceramic and its substrate, within a HAP, and (vi) the geometrical fit between two hard armour plates within a stacked body armour system. This paper will provide a User-friendly overview of all such interfaces and provide unique guidance as to their criticality and influence.

In this study, a picosecond (ps) laser was employed to produce micro-textures on ductile iron in linearly processing leading to significantly higher processing efficiency. The fabrication efficiency was increased about 1331 times as compared to the more common spot-by-spot texturing method. The ps laser induced graphene (LIG) structures were simultaneously fabricated in dimples, which further enhanced the surface tribological properties. The surface micro-textures were produced by forming micro-dimples on the substrate via the laser ablation process. The dimple diameter and area density were regulated by varying the key laser processing parameters, and were experimentally correlated to the tribological properties of the ductile iron substrate. To understand deeper into the wear reduction mechanism of the micro-dimples, simulation models based on the Reynold equation were established, which analyze the flow field pressure distribution and demonstrate the hydrodynamic lubrication effect of the micro-textures. The ball-on disk friction test showed that the area density of the micro-textures had a significant influence on the friction and wear properties. The micro-texture with the area density of 20 % and the average dimple diameter of 36 μm showed the highest volume wear rate reduction of 70 % and the friction coefficient reduction of 20 % respectively. The results indicated that the simultaneous laser in-situ generation of graphene micro-textures is an effective way of enhancing tribological properties on the ductile iron surface. It enhances the hardness of textured surfaces, thermal diffusion, debris capture ability, and fluid dynamic lubrication effect.

The paper presents a study on the ballistic performance of 3D woven wadded through-the-thickness angle-interlock fabrics (TTAI) fabric reinforced composites. Their energy absorption and damage morphology are examined experimentally through perforated ballistic test and X-CT (X-ray Computed Tomography). The results show that the wadded TTAI exhibits a 3.3% higher energy absorption and a 4.6% improved efficiency in energy absorption when compared to a plain weave fabric reinforced composite panel at an equivalent areal density. A 65.3% reduced delamination damage volume and a highly fibrillated failure morphology at the impact location are also noticed on the wadded TTAI reinforced composite, which implies a better utilization of the fiber strength by tensile fracture in absorbing the impact energy. The findings will instruct the future design of lightweight structures for ballistic protective uses, especially those applications with doubly curved shapes.

This work investigates the effect of hybridization and stacking sequence on the ballistic impact response of S2-glass/aramid/epoxy laminates. Different laminates were manufactured by vacuum infusion, one with only aramid fabrics (12 layers, K12), two with only S2-glass fabrics (12 or 18 layers, Gl12 and Gl18) and five interply hybrids (Gl3K9, [GlK]6, K6Gl6, Gl6K6, Gl9K3). Ballistic tests were performed according to EN1522- FB3, with the .357 Magnum FMJ projectile. The ballistic curves were determined to obtain the ballistic limit velocity (VBL), and in-plane damage area and through-the-thickness damage were analyzed. For the impact at 430 m/s, all laminates were perforated, and the Gl18 exhibited greater specific absorbed energy (26.6 J.m2/kg), with lower thickness and in-plane damage than the K12 (22.6 J.m2/kg) with a similar areal density (≈0.77 g/cm2). No significant differences in ballistic limits (pairing effect) were observed for the [GlK]6, Gl6K6 and K6Gl6 hybrids, and the Gl3K9 hybrid exhibited a positive hybrid effect. The areal density of laminates has shown a great influence on the final ballistic response. The results have shown that hybridization of aramid composites with S2-glass may enhance the impact absorption capability of hard composite armors, however, the ballistic limit velocity, which is a crucial parameter to assess ballistic shield performance, reduced.

Heat-assisted magnetic recording (HAMR) is one of the next generation technologies in data storage that can increase the areal density to beyond 1.5 Tb/in2. Near-field transducer (NFT) is a key component of the HAMR system that locally heats the recording medium by concentrating light below the diffraction limit using surface plasmons. In this work, we use density-based topology optimization for inverse design of NFT for a desired temperature profile in the recording medium. We first perform an inverse thermal calculation to obtain the required volumetric heat generation (electric field) for a desired temperature profile. Then an inverse electromagnetic design of NFT is performed for achieving the desired electric field. NFT designs for both generating a small heated spot size and a heated spot with desired aspect ratio in recording medium are demonstrated.

This paper focuses on the effects of chemical precipitation on the permeability of geotextile envelopes for a subsurface drainage system in arid areas by conducting precipitation experiments of the geotextile in static or flowing solution. The results show that the precipitation process is not significantly promoted or inhibited by the network structure of geotextile. The precipitates in the form of rhombus wrap around the fiber surface. The number of geotextile pores with the smaller diameters decreases significantly after precipitation experiments. As the increase of the area density of precipitates (ΔR), the variation of the pore area (ΔS) and the variation of permeability coefficient (ΔK) of the geotextile decrease rapidly at first and then slowly. The ΔK and ΔS VS ΔR data were best fitted with logarithmic trend line. This study provides a preliminary reference for quantifying the chemical clogging process of geotextile envelopes in arid areas.

In this paper, the post ballistic impact behaviour of kevlar-glass fibre hybrid composite laminates was investigated against 9×19 mm projectile. Eight different types of composite laminates with different ratios of kevlar woven fibre to glass fibre were fabricated using hand lay-up with epoxy matrix. Ballistic behaviour like ballistic Limit (V50), energy absorption, specific energy absorption and Back Face Signature (BFS) were studied after bullet impact. The results indicated that as the Percentage of glass fibre is increased there was a linear increment in the ballistic behaviour. Addition of 16% kevlar fabric, composite sample meets the performance requirement of NIJ0101.06 Level III-A. Since the maximum specific energy absorption was observed in Pure Kevlar samples and the adding of glass fibre increases the weight and Areal Density of the sample, further investigations need to be carried out to utilize the potential of glass fibre for ballistic applications.

Superlubricity is a fascinating phenomenon which attracts people to continuously expand ultralow friction and wear from microscale to macroscale. Despite the impressive advances in this field, it is still limited to specific materials and extreme operating conditions. Introducing a heterostructure with intrinsic lattice mismatch into delicate topologies mimicked from nature provides a promising alternative toward macroscopic superlubricity. Herein, 3D-printed MoS2/MoSe2 heterostructures with bioinspired circular-cored square/hexagonal honeycomb topologies were developed. Compared to 3D-printed Al2O3, all topological structures with both high hardness and excellent flexural strength achieve more than 30% decrease in the friction coefficient. The circular-cored hexagonal honeycomb composite with 30% area density exhibits a stable ultralow friction coefficient of 0.09 and a low wear rate of 2.5 × 10-5 mm3·N-1 m-1 under 5 N. Even under 10 N, a highly desirable coefficient value of 0.08 can be maintained within 370 s. The extraordinary ultralow friction could be attributed to the small contact area, high lubricant mass loading, efficient collection and storage of both abrasive debris and lubricant, and the self-orientation in the lubricating film. This work provides new insights into developing high-efficiency lubrication devices and aids in the industrial application of macroscopic superlubricity in future life.

It was difficult to solve the conflict of integrating the lightweight property, mechanical resistance, and broadband microwave absorption into one composite structure. Herein, the glass fiber (GF)/carbon fiber (CF) reinforced lightweight multifunctional metastructure with mechanical resistance and broadband microwave absorption was designed and optimized through the genetic algorithms and fabricated with the autoclave-vacuum bag technique. The proposed GF/CF reinforced metastructure (GF/CFRM) covered the −10 dB effective bandwidth in the full frequency band of 2–18 GHz with average reflectivity of −16.7 dB. The proposed electromagnetic theory was effective to predict the reflectivity of the metastructure. The GF/CFRM achieved the flexural strength of 42 MPa with the areal density and equivalent density of 8.26 kg/m2. The addition of the patterned resistive film introduced multiple absorption peaks in different frequency points. The integration of the lightweight property, load bearing, and broadband microwave absorption was realized.

Despite the low contribution of heavy ions to the total fluence in the space radiation environment, their radiobiological effect on the human body is extremely high. In this article, we investigated the radiation field which resulted from the interaction of galactic cosmic rays (GCRs), specifically some heavy ions and energies, typically encountered in space with a realistic multilayer sample of the International Space Station (ISS) Columbus module’s shielding wall. The quality factor, Q, and the normalized dose equivalent, H, derived from microdosimetric measurements for C, Ne, and Si ions behind different spacecraft wall configurations and materials are presented in this article. Particularly, carbon fiber, polyoxymethylene, and perspex with same areal density compared to currently used aluminum were investigated.

Laser surface modification of contact surfaces, which can generate arranged channels or micro-dimples, is an important factor that dictates several improvements in tribological performance, including lubrication lifetime, wear resistance, load-carrying capacity, and reduced friction coefficients. Patterns of combined textures having circular and sine wave shapes were created using an Nd:YAG laser. Pin-on-disk tribometer tests under oil lubrication were conducted over a range of test conditions. Moreover, an L9(34) orthogonal array experimental design was employed to determine the influence of parameters such as the area density, applied load, and sliding speed on the tribological characteristics. The results indicate that the combined textures effectively reduced the coefficient of friction compared with that of a polished surface. Among the investigated patterns, the texture with a 100-μm-groove-width pattern exhibited the lowest friction coefficient and wear rate. Analysis of variance suggested that the dimple density is the most important parameter influencing the friction coefficient at a confidence level of 95%.

Despite considerable achievements in the use of porous carbon in electrochemical double-layer capacitor or electrode of supercapacitor over the past few years, understanding the relationship between pore structure parameters and electrochemical performance has long been highly desirable. Herein, apricot shell lignin (ASL) was used to prepare activated carbon, after which the galvanostatic charge–discharge (GCD) test was performed. Meanwhile, the pore structure parameters of AAC were determined by the nitrogen adsorption–desorption test. The results confirmed that the AAC pore structure parameters were consistent with the inherent law of activation. Besides, in the low current density ranging from 0.50 A/g to 10.00 A/g, the micropore surface area density of AAC rather than other pore structure parameters (e.g., mesoporosity, micropore specific surface area, mesopore specific surface area) was linearly positively related to its mass-specific capacitance. Additionally, the average of linear fit coefficients between micropore surface area density and mass-specific capacitance was 0.92. Consequently, when using a three-electrode configuration with a 6 M KOH electrolyte, the micropore surface area density of activated carbon can be employed as a universal predictor of mass-specific capacitance in a low current density range 0.50–10.00 A/g.

In case of lightly loaded radial ball bearings, failure mechanisms other than fatigue such as smearing of raceways due to increased frictional torque and vibrations often prevail. Hence, attempts have been made herein for reducing the frictional torque and minimizing the vibrations of a radial deep groove ball bearing employing surface textures at the inner race. Nanosecond pulsed laser was used to create texture (involving micro-dimples having different dimple area density) on the inner race of test bearings. Using an in-house developed test rig, frictional torque and vibrational parameters were measured at different speeds and light loads (i.e. in vicinity of 0.01C, where C is dynamic load capacity of radial ball bearing). Significant reduction in frictional torque and overall vibrations were found in the presence of micro-dimples on inner race at light loads irrespective of operating speeds. Even without satisfying the minimum load needed criteria for the satisfactory operation, substantial reduction in smearing marks was found on the races of textured ball bearings in comparison to conventional cases.

In this article, we present a novel micromagnetic model for L10 ordered FePt grains based on their atomic structure. In this model, each monolayer of Fe atoms is represented by a magnetic moment vector and the entire grain consists of a stack of magnetic moments coupled by magnetostatic and nearest-neighbor exchange fields. The grain model enables simulation of incoherent magnetization switching, especially near the Curie temperature. The model is applied to simulate the heat-assisted recording process in granular L10 FePt thin-film media. One of the unique findings is that grains at transition centers could have a domain wall trapped within, provided sufficient grain height. The existence of these grains, whose magnetic moments could be fractional at transition centers, resulting in significant reduction of medium noise. The noise reduction is effectively equivalent to an increase of the number of grains across the read track width. Enhancing and controlling this mechanism by material engineering could lead to significant increase of area density capability, specifically, increase of track density, without decreasing grain size.

System-level requirements for heat-assisted magnetic recording at high areal density are presented in this article. The primary factors that affect bit error rate (BER) are spatial, or media, signal-to-noise ratio (SNR), reader SNR, and channel bit density (CBD). Spatial SNR is largely determined by the interaction between the writer properties and the media properties. For example, how well the thermal gradient matches the grain size. Spatial SNR also depends on how well the reader cross-track resolution matches the track pitch, and the quality of the written pattern. For any given level of spatial SNR, there exists a combination of CBD and reader SNR that results in the desired level of performance. This article elucidates some of the tradeoffs that may be needed to maintain BER as areal density increases, for different bit aspect ratio scenarios. For very high areal density, we show that the geometrical requirements are extremely aggressive, which will most likely require significant invention in head and drive architecture design.

Synthetic, non-degradable packaging materials have become a severe environmental threat, and therefore the demand is growing for environmentally friendly materials for sustainable packaging. This study presents a feasible method of developing a novel, sustainable packaging material using the Arecanut leaf sheath (ALS). CarboxyMethyl Cellulose was coated on the material for improving its mechanical properties. The results were compared with those of polythene: the most commonly used packaging material. The novel material has an areal density of 132.5 g per square meter and 1 mm thickness. The material also possesses a tearing strength of approximately 71% of polythene and exhibits approximately 5% elongation at failure. The bursting strength of the material was found to be three times higher (0.3 kg/cm2) than that of polythene (0.1 kg/cm2). The constitutive behaviour of the material was found to be orthotropic. The breaking force of the material was approximately 70% and 22% of polythene in lengthwise and widthwise directions, respectively. The transmittance of the material varied from 54 to 68% in the visible spectrum. Novel material shows a good thermal stability where initial degradation occurred in the temperature range of 200–375 °C.The tensile behaviour was also numerically modelled using the commercial finite element code LS-DYNA. The predicted stress–strain behaviour of the novel material by the numerical model is in close agreement with experimental results. ALS holds promise as a raw material in the development of transparent, sustainable packaging materials for a wide array of applications.

To provide useful component design guidance, micromagnetic simulations of heat-assisted magnetic recording (HAMR) must include estimates of the areal density (AD) of the recording system. In this work, we investigate the influence of both near field transducer (NFT) and medium design on AD. Exploring a range of medium and NFT designs we demonstrate that once the thermal gradient of the head and medium system is sufficient, the achievable jitter (and hence linear density) is governed by the magnetic properties of the medium. Including readback parameters, we outline requirements for HAMR recording systems capable of achieving >2 Tbpsi in hard disk drives with product margins.

A reduction in the track width of magnetic recording systems results in a welcome increase in areal density (AD), but also in the unfortunate appearance of extreme inter-track interference (ITI) that can severely deteriorate system performance. The effect of severe ITI may be mitigated through the use of coding schemes. In this paper, therefore, we present a rate-5/6 two-dimensional (2D) modulation code that is designed based on a proposed single-reader/two-track reading (SRTR) technique to cope with this serious problem in staggered bit-patterned magnetic recording (BPMR) systems. We then evaluate the bit-error rate (BER) performance of the proposed system in the presence of media noises, e.g., position and size fluctuations. Our simulation results indicate that, at the same user density (UD), the proposed system is better than an uncoded system by about 1.0 dB at the BER of 10 − 5 and is also superior to a conventional recording system.

Heat-assisted magnetic recording on bit patterned media dots with two magnetic structures is modeled. If the magnetic structures have different Curie temperatures two bits of information can be stored in each dot by writing at high and low temperatures. The areal density capability of the dual structure media was calculated and found to be in excess of 7 Tbit/in2, even when taking account of dot position distributions and magnetostatic fields from surrounding dots.

Recent growth in the cloud storage industry has created a massive demand for higher capacity hard disk drives (HDD). A sub-nanometer head media spacing (HMS) remains the most critical pre-requisite to achieve the areal density needed to deliver the next generation HDD products. Designing a robust head-disk interface (HDI) with small physical clearance requires a deeper understanding of slider dynamics, especially when the head flies in proximity to the disk surface. This paper describes a method using the magnetic read-back signal to characterize the head fly-height modulations as it undergoes a transition from a free-flying state to soft contact with the disk surface. A technique based on the magnetic fly-height sensitivity is introduced to identify the transition plane that corresponds to the onset of the touchdown process. Additionally, the proposed magnetic spacing based meteorology is used to study the effect of the air bearing stiffness and lubricant properties on the slider vibrations induced by intermittent head-disk interactions. The ability to accurately determine the transition plane corresponding to minimum stable flying conditions can help design a low clearance head-disk interface.

A stacked voltage domain SRAM is proposed as an effective leakage reduction technique where bit-cell arrays are split into two voltage domains (top and bottom) connecting in series between VDD and GND to generate a subthreshold retention voltage directly from a nominal supply with no area penalty or efficiency loss compared to the conventional voltage regulator approach. The Zigzag 8T bit-cell structure is chosen with an optimal transistor sizing to balance among hold stability, leakage, and area density. SRAM peripherals remains at full supply domain resulting in super-cutoff read for improved sensing margin and word-line overdrive for better write margin. A novel array swapping mechanism with a comprehensive timing control ensure stable access to arbitrary arrays within one system clock cycle. The proposed SRAM achieves 1.03-pW/b leakage at 0.58 V in 40 nm.

Ballistic performance of high-nitrogen steel (HNS) plates and RHA steel plates were evaluated against 7.62 mm ball and 12.7 mm armour piercing (AP) projectiles The impact velocities of 7.62 mm ball and 12.7 mm armour-piercing projectiles were 850 ± 10 m/s and 840 ± 10 m/s respectively. Critical thickness at which projectile is stopped was found from ballistic tests on different thickness targets and it was used for comparing the ballistic performance. HNS plates showed improved impact resistance (in terms of minimum areal density at which projectile is stopped) than that of RHA steel plates against both 7.62 ball and 12.7 mm armour piercing projectiles. Improved impact resistance of HNS plates could be correlated with its superior high strain rate flow stress values with respect to RHA steel. Microstructural evaluation revealed that adiabatic shear band induced plugging and ductile-hole growth are the major failure modes in both targets against 7.62 ball and 12.7 AP projectiles respectively.

In work reported here, the dynamic properties and low-velocity impact response of woven carbon/epoxy laminates incorporating a novel 3D interlaminar reinforcement concept with dense layers of Z-axis oriented milled carbon fiber SupercompositeTM prepregs, are presented. Impulse-frequency response vibration technique is used for non-destructive evaluation of the dynamic flexural modulus (stiffness) and loss factor (intrinsic damping) of woven carbon/epoxy control and SupercompositeTM laminates. Low-velocity punch-shear tests were performed on control and SupercompositeTM laminates according to ASTM D3763 Standard using a drop-weight impact test system. Control panels had all layers of 3K plain woven carbon/epoxy prepregs, with a dense interlaminar reinforcement of milled carbon fibers in Z- direction used in designing the SupercompositeTM laminate—both having same areal density. Impulse-frequency response vibration experiments show that with a 50% replacement of woven carbon fabric in control panel with milled carbon fibers in Z direction dynamic flexural modulus reduced 25% - 30% (loss in stiffness) and damping increased by about the same 25% - 30%. Low-velocity punch-shear tests demonstrated about 25% reduction in energy absorption for SupercompositeTM laminates with the replacement of 50% woven carbon fabric in control panel.

In this study, a numerical analysis of the ballistic performance of ceramic–metal composite structures is investigated. In the analysis, the two composites consist of distinct ceramics, namely Alumina and Boron Carbide tiles supported by the Aluminum plate were tested for numerical analysis. In both the structures, the size of the circular ceramic plates was 101 mm diameter and 25 mm thickness composed at the center of backed Aluminum metal plates having a backing thickness of 64 mm and an outer diameter of 152 mm. A cylindrical tungsten projectile (76.2 mm long and 7.62 mm diameter) was impacted with 1550 m/s velocity at the center of both the composites and the behavior of the impacted ceramic–metal composites were studied through LS-DYNA solver and validated through experimental results available in the literature. For studying the ballistic performance of the composite, different parameters were considered, namely the depth of penetration, ballistic limit, and areal density of the target. The performance of ceramic immensely depends upon the yield strength of backing and front ceramic material. In this study, the results have shown that, the B4C/Al outperformed Al2O3/Al in depth of penetration, in the ballistic limit by 44%, and in areal density by 14%. Hence, the Boron Carbide-Aluminum composite had better ballistic performance than others.

Knitted structures are progressively built up from row after row of knitted intermeshed loops known as knitted loops. Apart from this knitted loops, tuck or miss loops may be produced by varying the timing of the intermeshing sequence of the old loop and new loops. These loops are main and prominent part of the design of the weft knitted structures. Structures having float or miss loop exhibits many noticeable characteristics. The fabrics renders better surface appearance or color pattern. Dimensional stability is significantly improved. Fabric width is reduced and areal density is also increased considerably due to the presence of float loops in the structure. Therefore, the dimensional and physical features of different knitted structures having knit-miss loops may be studied carefully to find the influence of float stitch or loop on fabric width and areal density. In this project work, such an attempt has been made to specify some specific single jersey structures, which will be ensured as an effective tool for product research and development as well as for meeting up customer’s quality requirements of high class products.

ZnO seed layers were deposited on silicon and sapphire substrates by the pulsed laser deposition (PLD) method, and ZnO nanorod arrays with different orientation degrees were grown using the chemical vapor deposition (CVD) method. Flat-type gas sensors based on the ZnO nanorod arrays were fabricated, and their gas sensitivity properties were studied. The ZnO seed layer with a thickness of approximately 450 nm exhibits high c-axis orientation and possesses few defects. The ZnO nanorods fabricated on both of the substrates grow along the [0001] direction and contain a large number of oxygen vacancy defects. These nanorods have lengths of 8~10 μm and diameters of 200~500 nm. The ZnO nanorods grown on the silicon substrate are perpendicular to the surface of the substrate, and their areal density is approximately 3.0×108/cm2, while those grown on the sapphire substrate exhibit a lower orientation degree, and their areal density is approximately 0.9×108/cm2. The largest response of the gas sensor for gaseous alcohol reaches 48.2, and the optimal operating temperature for all of the sensors is approximately 280 °C. The gas sensitivity property of the silicon-based sensor is superior to that of the sapphire-based sensor, and the corresponding sensing mechanism is discussed.

Compact heat exchangers have an area density of about 700 m2/m3. In compact heat exchangers, fins are used to enhance the thermal performance. Various type of fins in terms of their form (such as p...

This paper investigates an analytical illustration of ignition conditions for the aneutronic reaction of proton-boron plasma in the presence of the magnetic field for fusion. In particular, the criterion for this plasma target is derived through two-temperature Lindl–Widner diagrams. Since the heating and cooling terms in the energy balance equation are affected by inequality between ions and electrons temperature combined with the impact of the magnetic field, the reduction of energy loss as well as the areal density parameter will increase the fusion rate. It will also relax the requirements of ignition conditions. Therefore, numerical derivations of ignition conditions at stagnation are performed involving the energy balance equation. The additional parameter applied other than electron and ion temperature as well as areal density is the magnetic field dependent B/ρ. It is shown that as B/ρ develops the required areal density decreases. For ions temperature of Ti < 1000 keV and electrons temperature of Te < 110 keV, the equation has real solutions for the areal density of ρR < 6 g/cm2. Furthermore, it is shown that the B/ρ parameter can be set at approximately 106 G cm3/g value. It shows the magnetic field has more effect than DT case and can reduce the driver requirements significantly. A comparison of this model with DT magnetized case shows that this model of p11B fuel is intermediate between experimental results of p11B non-magnetized and DT magnetized in the two-temperature model.

This paper reports process development and material characterization studies of Inconel-625 (IN625) using laser powder bed fusion (LPBF)-based additive manufacturing at higher layer thickness (100 µm). Conventionally, layer thickness up to 50 µm is used in LPBF due to process instability issues at higher layer thickness. However, successful development of LPBF with higher layer thickness will yield higher build rate. Therefore, systematic parametric investigations are carried out by varying laser power (P), scan speed (v) and hatch spacing (h) from 150 to 450 W, 0.02 to 0.08 m/s and 0.150 to 0.350 mm, respectively, with 100 µm layer thickness. The obtained results are compiled as a function of combined parameter—laser energy density (LED). Samples with relative area density > 99% are achieved for LED of 150, 240 and 360 J/mm3. Geometrical studies show that the deviation from nominal length and range of height of the sample decreases and increases with an increase in LED, respectively. X-ray diffraction shows the presence of face-centered cubic γ-phase at all the conditions with fine crystallites. The microstructure is a mix of cellular and dendritic with the primary arm width increasing with LED. Micro-hardness studies show that the hardness decreases slightly with an increase in LED, while automated ball indentation tests indicate the increase in energy storage capability with increase in LED. The micro-hardness, yield strength and ultimate tensile strength of LPBF built IN625 structure at 100 µm are found to be higher than that of the conventional and laser directed energy deposited IN625 structures and similar to that of the LPBF built IN625 structures at lower layer thickness. The study provides insight into LPBF of IN625 at 100 µm layer thickness and paves way for fabricating components at higher layer thickness with favorable mechanical properties.

The application of group-IV based ferromagnetic-nanodots (NDs) such as Fe3-silicide NDs to a floating gate in MOS memories has been attracting much attention from the view point of new functionality to control charging and discharging properties in NDs floating gate by the tunnel magnetoresistance effect between ferromagnetic NDs and gate electrodes [1-2]. In our previous work, we demonstrated the formation of high density Fe3Si-NDs on ultrathin SiO2 by exposing ultrathin Fe films deposited on Si-NDs, which were self-assembled on OH-terminated SiO2 layers by controlling the early stages of low-pressure chemical vapor deposition (LPCVD) using SiH4, to remote H2 plasma (H2-RP) [3]. In this work, we extend our research to the characterization of their local electron transport properties measured with a magnetic probe under external magnetic field. An atomic force microscope (AFM) image taken after the SiH4-LPCVD, and subsequent ultrathin Fe-film deposition and H2-RP exposure confirmed the formation of NDs with an areal density as high as ~2.7×1011 cm-2 and with an average height of ~5.9 nm which were evaluated from a size distribution of NDs obtained from the AFM image. In addition, from in-plane and perpendicular magnetization curves (M–H curves) measurements, a coercivities of 180 and 220 Oe were obtained for the in-plane and perpendicular directions, respectively. To evaluate local electron transport properties, a CoPtCr-coated AFM probe was scanned on the sample surface under application of an external magnetic field to take topographic and current images simultaneously where a DC bias of -2.0 V was applied to the AFM probe with respected to an Al bottom-electrode of the sample. The magnetization of the tip was initially set along the upward direction, and upward (positive) or downward (negative) external magnetic fields were applied to the NDs by placing the NdFeB magnet under the sample. When a positive field of 1.5 kOe was applied to the sample in the same direction as the initial tip magnetization, a clear correlation between the topographic images and current images was observed, namely the clear current image with a high contrast among dots and SiO2 (Fig. 1 (a) and (b)). However, a distinct decrease in the current level was detected when a negative field of 0.35 kOe was applied. Notice that, when a positive field of 1.5 kOe was applied to the sample in the same direction as the first magnetization, an almost complete recovery of the resistive state was observed. We also confirmed a reversal of the tip magnetization at a magnetic field of 1.5 kOe from the observation of the reversed contrast in a magnetic force microscope image of a floppy disk taken with the tip exposed to a field of 1.5 kOe. Based on these results, the increase in the resistance by the application of the magnetic field of 0.35 kOe in the opposite direction to the tip magnetization direction can be interpreted in terms of the reversal of the magnetization direction of the dots because the perpendicular coercivity of the dots is 220 Oe. After the re-magnetization at 1.5 kOe, the magnetization direction of the dots and tip can be aligned in parallel. These results indicate that with the application of a magnetic field of 0.35 kOe, the resistive state can be changed by controlling the magnetization directions of the dots. In conclusion, we evaluated the local electron transport properties of Fe3Si-NDs with the areal density as high as ~1011 cm-2 on an ultrathin SiO2/n-Si(100) by using the magnetic cantilever under the external magnetic field. We confirmed at room temperatures that there is a clear change in the contrast of the current images in which current through the NDs depends on the relative directions of magnetization between the NDs and the magnetic cantilever. Reference [1] Y. Nakamura, et al., Jpn. J. Appl. Phys. 50, 015501 (2011). [2] S. H. Sun, et al., Science 287, 1989 (2000). [3] J. Wu et al., 8th ISCSI, WP2-18 (Sendai, 2019). Figure 1

This research work investigated the influence of carding parameters on different properties. In this study an attempt has been made to change the fibre orientation by changing the carding parameters such as feeder speed, cylinder speed and doffer speed keeping the same areal density of fabrics. In a combination of three different levels of feeder, cylinder and doffer speeds were also considered for sampling plan to create a three-factors three-levels Box-Benkhen Design for a better explanation of results. The fibre orientation was measured by using both direct (image analysis) and indirect (lindslay’s cutting and combing) method. The properties such as bursting strength, filtration efficiency and pressure drop were evaluated. The properties were analyzed and explained in the light of fibre orientation. It was found that the considered carding parameters influenced the fibre orientation to a great extent and the properties are influenced by the fibre orientation. In the end, an overall optimization has been done to achieve maximum filtration efficiency with minimum pressure drop and moderate busting strength.