Kinds Of Flux Research Articles

Effects of dyes on tensile strength and thermal damage of laser biological tissue soldering

Laser tissue welding is a hot issue in surgical research due to its advantages of non-contact, instant water tightness, no suture removal, no rejection and anti-infection. However, the contradiction between strength and thermal damage has not been solved completely. The addition of dye can solve the problem. Therefore, in order to improve the welding strength and quality, this paper studies the influence of different position and concentration of dye on the welding strength and determines the optimal concentration and applied position. Two kinds of flux were prepared, which were based on bovine serum albumin solution and stained with indocyanine green and methylene blue respectively. Comparing the welding effect of flux, the indocyanine green group is more remarkable. When the concentration of indocyanine green is 2.0 mg/mL, the maximum tensile strength reaches 19.32 ± 1.22 N/cm2, which is significantly higher than that of the control group without flux. When the flux is applied to the front side, the tensile strength is higher than the reverse side group. Two kinds of flux can effectively reduce the thermal damage. Our study demonstrates that indocyanine green and methylene blue are significant organic chromophores in laser welding process, which can promote the efficiency of photo-thermal conversion, improve welding strength and reduce thermal damage.

Orthogonal optimum design of parameters of flux used for low carbon bainitic steel

L8 (27) orthogonal test table is applied to design eight kinds of flux, and arranged with SiO2, ZrO2 and TiO2 as three factors. The microstructure, morphology and mechanical properties of low carbon bainitic steels are investigated by means of optical microscope, scanning electron microscope, transmission electron microscope, tensile testing machine and instrumented drop weight impact tester with oscilloscope. The results indicate that the optimum composition rate is as follows: 20% SiO2, 10% ZrO2, and 6% TiO2, and the interaction between ZrO2 and TiO2 is obvious. The microstructure of deposited metal of low carbon bainitic steel is mainly formed by acicular ferrite and granular bainite. The acicular ferrite is paralleled distribution, and plenty of fine sheet Martensitic–Austenitic constituents are dispersing, which can hinder crack propagation and improve strength and toughness. The impact energy is up to 109.7 J at − 20 °C, and the ratio of brittle fracture termination load to maximum impact load is 0.378, ensuring excellent crack arrest toughness.

Solderability of Electroless Nickel Alloys Using Wetting Balance Technique

Solderability of electroless nickel-alloy deposits was investigated by the wetting balance technique. The wetting time, wetting force and dewetting can be obtained from the wetting curve. Four parameters, wetting time, percentage of theoretical force, stability of wetting and solderability index, were applied to determine the effects of the soldering variables including two kinds of flux, substrates of electroless nickel-alloy deposits and their solderability. In general, wetting time decreases with an increase in soldering temperature. The rosin-activated flux has a stronger fluxing effect than organic acid. Among the investigated items, solderability index and contact angle are quite sensitive to the base metal material. The electroless Ni–Cu–P deposit and the electroless Ni–P with Au-coated deposit exhibit good wetting behavior with contact angles of 25°<θ<45° when using RA flux. On the other hand, poor wettability, with contact angles of 65°<θ<90°, was observed for the deposits investigated in this work using OA flux.

New methodology for the determination of mass transport rate from rotating disks and/or cylinders in liquid

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被覆剤中のMn及びSiの脱酸効果に関する研究(第1報)

熔接棒の被覆剤中にMn及びSiを配合するに当つて,製鋼における脱酸理論(Mn及びSiの共同脱酸と,それによつて生する蛻酸生成物の諸現象)が,熔接の脱酸にも深い関連があると考え研究を行つた.そして実驗の結果次のことが解つた.a)被覆剤中,適量の脱酸剤を配合することによつて被覆熔接棒は著しく改良せられるが,製鋼時に老えられる〔Mn〕と〔Si〕の濃度割合に関する条件は,熔接時においても適合する条件である.b)特に良好な熔着鋼を得るには,被覆熔接棒の〔Mn〕及び〔Si〕の濃度割合は,心線中のMn%及びSi%も含めて〔Mn〕:〔Si〕=4.0%:0,5%であることが望ましい.