Recent Progresses of Welding and Joining Engineering

Computational Study of Quenching Effects on Growth Processes and Size Distributions of Silicon Nanoparticles at a Thermal Plasma Tail

“…It can express a size distribution with any shape so that it needs high costs of computational resources and time. Type B describes collective nanoparticles’ growth by simultaneous nucleation, condensation, and coagulation by a simple set of two aerosol equations and one vapor equation so that the computational costs are low [ 26 , 27 , 28 , 29 , 57 , 58 ]. However, it does not express a dispersed size distribution because it calculates physical quantities by averaged size approximation.…”

“…The number and size of nanoparticles are affected by temperature and flow fields in and around thermal plasma through growth processes [ 25 ]. Strong cross-correlations between the temperature at an upstream plasma fringe and nanoparticle concentration in a downstream region have been found for a transferred arc plasma system [ 26 , 27 ] and for a non-transferred arc plasma jet in two-dimensional [ 28 ] and three-dimensional fields [ 29 ] in recent numerical studies using a method suitable for simulating dynamic behaviors of thermal plasma–nonionized gas coexisting flows [ 30 ]. Actually, to control temperature and flow fields and to control nanoparticle growth processes in ICTP systems, several experimental studies adopted quenching strategies using a water-cooled coil [ 31 ], a water-cooled ball [ 15 , 32 ], direct plasma control by pulse modulation [ 33 ], counterflow injection [ 18 , 34 ], and radial gas injection [ 35 , 36 ].…”

Particle simulation of nugget formation process during steel/aluminum alloy dissimilar resistance spot welding and thickness estimation of intermetallic compounds

“…ティグ溶接やミグ溶接の溶融池対流現象 [10][11][12][13] ，ミグ溶接やフ ラックスコアードアーク溶接の溶滴移行現象 14,15) ，サブマー ジアーク溶接現象 16) などの溶接・接合分野においても応用 されており [17][18][19][20][21]…”

In situ measurement of ultrasonic behavior during lap spot welding with laser ultrasonic method

“…As the object becomes very hot during welding, it is necessary to apply an inspection method that is measurable even in severe environments. Appearance measurement with a visual camera and temperature measurement with thermography are non-contact methods and are often used as in-process monitoring methods [1,2], including additive manufacturing [3]. However, they are restricted to external information.…”