Asuka Suzuki

To elucidate the possibility of controlling the microstructure and mechanical properties of Al–Si alloys additive-manufactured by laser powder bed fusion (L–PBF), the relationship among the laser conditions, microstructural characteristics (crystal grain, cellular microstructure, and solute Si in α-Al matrix), and tensile properties of L–PBF manufactured AlSi12 alloy samples was investigated. The crystal grain size and fraction of <001> oriented α-Al crystal grains toward the building direction

The hydrogen permeation coefficient () is generally used as a measure to show hydrogen permeation ability through dense metallic membranes, which is the product of the Fick's diffusion coefficient (<i>D</i>) and the Sieverts' solubility constant (<i>K</i>). However, the hydrogen permeability of metal membranes cannot be analyzed consistently with this conventional description. In this paper, various methods for consistent analysis of hydrogen permeability are reviewed. The derivations of the de

The effects of heat treatments on the compressive properties of a lattice‐structured AlSi10Mg alloy with a body‐centered‐cubic‐type unit cell fabricated by selective laser melting are investigated. The as‐fabricated lattice specimen fractures and does not exhibit plateau region. Fractography suggests that the crack preferentially propagates along the α‐Al/Si eutectic microstructure near the α‐Al grain boundaries in the as‐fabricated lattice specimen. The heat treatments at 300 °C for 2 h and at

The alloying effects of chromium, molybdenum, tungsten, iron and cobalt on the hydrogen solubility of vanadium have been investigated systematically. The addition of iron or cobalt into vanadium decreases the hydrogen solubility more significantly than chromium, molybdenum and tungsten. Thus, the addition of iron or cobalt into vanadium improves the resistance to hydrogen embrittlement of the vanadium alloy itself effectively. It is also found that, in view of the new description of hydrogen per

A Single laser scan was performed on a sintered WC/Co composite and the process conditions were optimized to realize a WC/Co two-phase microstructure in a WC/Co composite fabricated by laser powder bed fusion (L-PBF). Laser irradiation on the sintered WC/Co composites generated two different microstructural regions. One is composed of WC and Co phases (WC/Co two-phase region), and the other includes W2C and W3Co3C phases (WC decomposition region). In the L-PBF-fabricated WC/Co composites, these

Metal additive manufacturing (AM) enables the fabrication of lattice-structured heat sinks with enhanced heat transfer properties. The lattice structural features for enhancing heat transfer and suppressing pressure loss need to be clarified. To describe the structural features dominating heat transfer and pressure loss, eleven structural parameters consisting of three groups, namely the area, hydraulic diameter, and effective flow path, are proposed and used as inputs for the neural network (NN

A concept for alloy design of hydrogen permeable membrane with high hydrogen permeability and long-term durability has been proposed in view of the PCT factor, fPCT, and the ductile-to-brittle transition hydrogen concentration, DBTC. As an example, V–10mol%Fe alloy has been designed for low operative temperature, which exhibits excellent and stable hydrogen permeability for at least 1000 hours at 573 K without brittle fracture.