Abstract Metal additive manufacturing technology requires a real-time monitoring and feedback control system to assure the quality of final products. In particular, it is essential reveal phenomena recoating melting-solidification processes in laser powder bed fusion using because they influence strongly occurrence defects. This study was conducted elucidate correlation among characteristics, conditions, surface morphology process determine relationship between product quality. To this end,...

Pure copper is utilized as a material for products with complicated shape and high thermal conductivity such heat exchangers. However, it difficult to fabricate pure parts density by the selective laser melting (SLM) process. One of reasons considered be its which in melt pool rapidly diffuses away. Additionally, lower rate energy absorption fiber power makes size smaller. In this research, optimum fabrication condition high-purity 99.9% fabricated SLM process was investigated evaluating...

Laser powder additive manufacturing (PBF-LB) is an method capable of producing high-precision and fully dense parts. However, nondestructively quality assurance no internal defects remains challenging. Mitigating requires elucidating their formation mechanism improving the PBF-LB process conditions. Therefore, we developed in-situ monitoring system that combines surface morphology measurement by fringe projection thermal field with a high-speed camera. On heterogeneous surfaces in practical...

Recently, high-entropy alloys (HEAs) have attracted much attention because of their superior properties, such as high strength and corrosion resistance. This study aimed to investigate the influences process parameters on microstructure mechanical properties CoCrFe NiTiMo HEAs using a laser-based powder bed fusion (LPBF) process. In terms laser power scan speed, map was constructed by evaluating density surface roughness as-built specimen optimize products. The specimens fabricated at...

The availability of an in-situ monitoring and feedback control system during the implementation metal additive manufacturing technology ensures that high-quality finished parts are manufactured. This study aims to investigate correlation between surface texture internal defects or density laser-beam powder-bed fusion (LB-PBF) parts. In this study, 120 cubic specimens were fabricated via application LB-PBF process IN 718 Ni alloy powder. 35 areal surface-texture parameters manufactured...

In this study, the effects of powder characteristics on bed properties and subsequent impacts these melt solidification were investigated. To end, eight stainless-steel powders with varying examined. The process maps generated for also assessed, focusing their melt-solidification behavior implications buildability (i.e., product quality). build density distribution across map exhibited substantial variations. This variability was primarily attributed to distinct melting behaviors associated...

Additive Manufacturing (AM) technology has advantages in building free shape and simplification of manufacturing process. In order to manufacture the high quality parts, it is important find out optimum fabrication parameters such as laser power, scan speed, pitch so on. this research, conditions under power speed were investigated fabricate sound parts Al-10Si-0.4Mg alloy using a SLM machine equipped with 1 kW single mode fiber laser. As result, effective process window map was found by...

Brazing of a stainless steel to various aluminum alloys was carried out using an Al-Si filler metal and fluoride-active flux in air. The brazeability remarkably different by the brazing conditions. It considered that differences were originated with compositions base metals metal, solidus temperature partially melting behavior alloys, surface oxide film layers both metals. On other hand, obstruction identified as rapid reaction between which makes molten disappear at joining interface before...

In this work, we applied eddy-current-testing-based HTS-SQUID non-destructive inspection (ECT-based NDI) system for of metal 3D additive manufacturing (AM) objects, which were made AlSi10Mg powder with bed fusion (PBF) method. The combines an ECT probe gradiometer as high sensitive readout magnetic sensor in low frequency range to overcome disadvantage conventional ECT. We prepared 5 samples different densities by changing parameters the PBF process. Densities #1–#5 estimated be 2.65, 2.64,...

Recently, additive manufacturing (AM) technology has been paid great attention in the aerospace, medical and automotive fields because of possibility high-performance parts. In this paper, new development metal laser AM technology, especially powder bed fusion type deposition machines, analysis melting-solidification phenomenon melt pool, simulation, structure simulation thermal deformation are reviewed.

For the future construction of large scale space platform on earth orbit, high specific strength and modulus engineering materials will be required to braze in space. In this research, combination carbon/carbon composites titanium is chosen it investigated that effect cross-ply angle brazing interface shear microstructure at interface. A 2-D laminated C/C plates with [0°/90°]S, [+45°/-45°]S [30°/-60°]S were prepared. They brazed pure tablet vacuum using active filler Ag-32.25Cu-1.75Ti 830°C...

The brazing of C/C composites and Inconel-600 Ni-based heat resistant alloy was conducted using Fe-Ni-Cr-P-Si filler with inserting various thickness Nb foil as stress relief interlayer. SEM observation cross section interface revealed that resolved into the layer on side. diffused to surface acted active metal element enhance wettability molten graphite matrix during process. variation in shear strength values brazed joint suggested should be remained at least 100 μm.

In order to clarify such brazing conditions for making sound joints of Al-alloys stainless steel as wet the Al-Si filler on before rapid isothermal solidification filler, time is estimated by numerical analysis and also measured experimentally. The conducted process A1050 pure aluminum base metal BA4045 aluminum-silicon filler. contains both initial dissolution molten follow-ing behavior. movement solid-liquid interface calculated total estimated. experiment between same combination metals...

Braze Pressure Welding (BPW) with high frequency induction heating has been invented as the new joining method for welding general steel pipes on-site piping without danger of fire and dispersion in joint properties due to welder's skill. In BPW, a brazing filler is interlaid between mating surfaces be joined. The melts by up temperature, then pressure discharges it from interface. At same time, base metals are pressure-welded each other, that discharged liquid forms fillets around area....

Characteristics of hydrogen permeation in the stainless steel 304 modified by either facing, ion sputtering, carbon coating or annealing were investigated order to establish safe hydrogen-energy-infrastructure using welding. A stationary flux from surface was measured a system with an orifice. The pressure difference specimen able maintain constant controlling gas flow rate orifice low vessel. permeability two cases thin fine facing and that annealed at 1370K for 2 hours. In these cases,...