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    Dependence of Electrical Resistivity on Temperature and Sn Content in Pb-Sn Solders
    (SPRINGER, 2011) Cadirli, E.; Boyuk, U.; Kaya, H.; Marasli, N.; Aksoz, S.; Ocak, Y.
    Pb(100-x)-Sn-x solders (x = 5 wt.%, 10 wt.%, 20 wt.%, 35 wt.%, 50 wt.%, 60 wt.%, 61.9 wt.%, and 95 wt.%) were directionally solidified upward with a constant growth rate (V = 37.4 mu m/s) in a temperature gradient (G = 4.8 K/mm) in a Bridgman-type growth apparatus. The variations of electrical resistivity (rho) with temperature in the range of 323 K to 423 K for the directionally solidified Pb-Sn solders were measured. The present measurements indicate that the electrical resistivity of the directionally solidified Pb-Sn solders increases with increasing temperature, whereas the resistivity of the Pb-Sn solders decreases with increasing Sn content. The dependency of the Lorenz number (L) on temperature and Sn content for the Pb-Sn solders was also investigated based on the Wiedemann-Franz law by using the measured values of the thermal (K) and electrical (sigma) conductivity for the same alloys.
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    Dependency of Microstructural Parameters and Microindentation Hardness on the Temperature Gradient in the In-Bi-Sn Ternary Alloy with a Low Melting Point
    (KOREAN INST METALS MATERIALS, 2008) Kaya, H.; Boyuk, U.; Cadirli, E.; Ocak, Y.; Akbulut, S.; Keslioglu, K.; Marasli, N.
    The ternary alloy In-21.5 at.% Bi-17.8 at.% Sn, which has a melting point of 60 degrees C, was directionally solidified upward with a constant growth rate (V = 3.2 mu m/s) and different temperature gradients (G = 0.91 K/mm to 2.85 K/mm) by using a Bridgman-type directional solidification furnace. The lamellar spacings (lambda) and microhardness (H(v)) were measured from both the transverse and longitudinal sections of the samples. The dependence of the lamellar spacings (lambda) and microhardness (H(v)) on the temperature gradients (G) were determined by means of linear regression analysis. According to these results, the value of lambda decreases as the value of G increases and the value of Hv increases for a constant V. The results obtained in this work are compared with previous similar experimental results obtained for binary or ternary alloys.
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    Dependency of the thermal and electrical conductivity on the temperature and composition of Cu in the Al based Al-Cu alloys
    (ELSEVIER SCIENCE INC, 2010) Aksoz, S.; Ocak, Y.; Marasli, N.; Cadirli, E.; Kaya, H.; Boyuk, U.
    The variations of thermal conductivity with temperature for Al-[x] wt.% Cu, x = 3, 6, 15 and 24 alloys were measured by using a radial heat flow apparatus. The variations of electrical conductivity of solid phases versus temperature for the same alloys were determined from the Wiedemann-Franz and Smith-Palmer equations by using the measured values of thermal conductivity. From the graphs of thermal and electrical conductivity versus temperature, the thermal conductivity of the solid phases at their melting temperatures, and the thermal temperature and the electrical coefficients for the same alloys were obtained. Dependency of the thermal and electrical conductivity on the composition of Cu in the Al based Al-Cu alloys were also investigated. According to present experimental results, the thermal and electrical conductivity of Al-[x] wt.% Cu, x = 3, 6, 15 and 24 alloys linearly decrease with increasing the temperature and composition of Cu. The enthalpy of fusion and the specific heat change during the transformation for the same alloys were determined from cooling trace during the transformation from eutectic liquid to eutectic solid by means of differential scanning calorimeter (DSC). (c) 2010 Elsevier Inc. All rights reserved.
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    Determination of Interfacial Energies for Solid Al Solution in Equilibrium with Al-Cu-Ag Liquid
    (KOREAN INST METALS MATERIALS, 2010) Keslioglu, K.; Ocak, Y.; Aksoz, S.; Marasli, N.; Cadirli, E.; Kaya, H.
    The equilibrated grain boundary groove shapes of a solid Al solution in equilibrium with Al-Cu-Ag liquid were observed from a quenched sample using a radial heat flow apparatus. The Gibbs-Thomson coefficient, solid-liquid interfacial energy, and grain boundary energy of the solid Al solution were determined from the observed grain boundary groove shapes. The thermal conductivity of the solid phase for Al-16.42 at.% Ag-4.97 at.% Cu and Al-16.57 at.% Ag-11.87 at.% Cu alloys and the thermal conductivity ratio of the liquid phase to the solid phase for Al-16.57 at.% Ag-11.87 at.% Cu alloy at the melting temperature were also measured with a radial heat flow apparatus and a Bridgman-type growth apparatus, respectively.
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    Determination of interfacial energies of solid Sn solution in the In-Bi-Sn ternary alloy
    (ELSEVIER SCIENCE INC, 2009) Akbulut, S.; Ocak, Y.; Marasli, N.; Keslioglu, K.; Kaya, H.; Cadirli, E.
    The equilibrated grain boundary groove shapes of solid Sn solution (Sn-40.14 at.% In-16.11 at.% Bi) in equilibrium with the In-Bi-Sn liquid (In-21.23 at.% Bi-19.04 at.% Sn) were observed from the quenched sample at 59 degrees C. Gibbs-Thomson coefficient, solid-liquid interfacial energy and grain boundary energy of the solid Sn solution have been determined from the observed grain boundary groove shapes. The thermal conductivity of solid phase for In-21.23 at.% Bi-19.04 at.% Sn alloy and the thermal conductivity ratio of liquid phase to solid phase at the melting temperature have also been measured with radial heat flow apparatus and Bridgman type growth apparatus, respectively. (C) 2008 Elsevier Inc. All rights reserved.
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    Determination of solid-liquid interfacial energies in the In-Bi-Sn ternary alloy
    (IOP PUBLISHING LTD, 2008) Akbulut, S.; Ocak, Y.; Marasli, N.; Keslioglu, K.; Kaya, H.; Cadirli, E.
    The equilibrated grain boundary groove shapes of solid In(2)Bi solution in equilibrium with the In-Bi-Sn eutectic liquid were observed from a quenched sample at 59 degrees C. The Gibbs-Thomson coefficient, solid-liquid interfacial energy and grain boundary energy of the solid In2Bi solution have been determined to be (1.42 +/- 0.07) x 10(-7) Km, (49.6 +/- 5.0) x 10(-3) Jm(-2) and (97.1 +/- 10.7) x 10(-3) Jm(-2), respectively, from the observed grain boundary groove shapes. The thermal conductivities of the solid phases for In-21.23 at% Bi-19.04 at% Sn and In-30.5 at% Bi-3 at% Sn alloys and the thermal conductivity ratio of the liquid phase to the solid phase for In-21.23 at% Bi-19.04 at% Sn have also been measured with a radial heat flow apparatus and a Bridgman type growth apparatus, respectively, at their melting temperature.
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    Experimental determination of interfacial energies for Ag2Al solid solution in the CuAl2-Ag2Al system
    (IOP PUBLISHING LTD, 2009) Ocak, Y.; Akbulut, S.; Keslioglu, K.; Marasli, N.; Cadirli, E.; Kaya, H.
    The equilibrated grain boundary groove shapes of solid solution Ag2Al in equilibrium with an Al-Cu-Ag liquid were observed from a quenched sample with a radial heat flow apparatus. The Gibbs-Thomson coefficient, solid-liquid interfacial energy and grain boundary energy of the solid solution Ag2Al have been determined from the observed grain boundary groove shapes. The thermal conductivity of the solid phase and the thermal conductivity ratio of the liquid phase to solid phase for Ag2Al-28.3 at the % CuAl2 alloy at the melting temperature have also been measured with a radial heat flow apparatus and Bridgman type growth apparatus, separately.
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    Experimental determination of solid-solid and solid-liquid interfacial energies of solid epsilon (CuZn5) in the Zn-Cu alloy
    (ELSEVIER SCIENCE SA, 2009) Kaygisiz, Y.; Akbulut, S.; Ocak, Y.; Keslioglu, K.; Marasli, N.; Cadirli, E.; Kaya, H.
    The equilibrated grain boundary groove shapes of solid epsilon; (CuZn5) in equilibrium with Zn-1.75 at.% Cu peritectic liquid and solid epsilon (CuZn5) in equilibrium with solid Zn solution (Zn-2.83 at.% Cu) were observed from a quenched sample. The Gibbs-Thomson coefficient, solid-liquid interfacial energy and grain boundary energy of solid epsilon (CuZn5) in equilibrium with Zn-1.75 at.% Cu peritectic liquid have been determined to be (4.9 +/- 0.3) x 10(-8) K m, (76.0 +/- 9.1) x 10(-3) J m(-2) and (150.3 +/- 19.5) x 10(-3) J m(-2), respectively. For the first time, the equilibrated grain boundary groove shapes of solid epsilon (CuZn5) in equilibrium with solid Zn solution have been observed. The Gibbs-Thomson coefficient, solid-solid interfacial energy and grain boundary energy of solid epsilon (CuZn5) in equilibrium with solid Zn have also been determined to be (4.7 +/- 0.3) x 10(-8) K m, (72.9 +/- 8.7) x 10(-3) J m(-2) and (144.1 +/- 18.7) x 10(-3) J m(-2), respectively from the observed grain boundary groove shapes. The thermal conductivities of solid Zn solution and solid epsilon; (CuZn5) phase (Zn-12 at.% Cu) have been measured with radial heat flow apparatus. The thermal conductivity ratios of the equilibrated liquid phase to solid phase for Zn-1.75 at.% Cu and Zn-12 at.% Cu alloys have also been measured with Bridgman type growth apparatus. (C) 2009 Elsevier B.V. All rights reserved.
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    Interfacial energies of solid CuAl2 in the CuAl2-Ag2Al pseudo binary alloy
    (ELSEVIER SCIENCE SA, 2010) Ocak, Y.; Aksoz, S.; Keslioglu, K.; Marasli, N.; Cadirli, E.; Kaya, H.
    Gibbs-Thomson coefficient, solid-liquid interfacial energy and grain boundary energy are important parameters for people doing comparisons between experimentally observed solidification morphology and predictions from theoretical models. Thus the Gibbs-Thomson coefficient, solid-liquid interfacial energy and grain boundary energy of solid CuAl2 in the CuAl2-Ag2Al pseudo binary system have been determined from observed grain boundary groove shapes. The variation of thermal conductivity of solid CuAl2 with temperature has also been measured by using a radial heat flow apparatus. (C) 2010 Elsevier By. All rights reserved.
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    Interfacial energy of solid In2Bi intermetallic phase in equilibrium with In-Bi eutectic liquid at 72 degrees C equilibrating temperature
    (ELSEVIER SCIENCE INC, 2008) Akbulut, S.; Ocak, Y.; Marasli, N.; Keslioglu, K.; Boeyuek, U.; Cadirli, E.; Kaya, H.
    A radial temperature gradient on the sample was established by heating from centre with a single heating wire and cooling the outside of sample at -10 degrees C with a heating/refrigerating circulating bath containing an aqueous ethylene glycol solution. The equilibrated grain boundary groove shapes of solid In2Bi (In-33.2 at.% Bi) in equilibrium with In-Bi eutectic liquid (In-22 at.% Bi) were observed from quenched sample at 72 degrees C. Gibbs-Thomson coefficient and solid-liquid interfacial energy of solid In2Bi in equilibrium with In-Bi eutectic liquid have been determined to be (11.3 +/- 0.6) x 10(-8) K m and (47.8 +/- 4.8) x 10(-3) J m(-2) from the observed grain boundary groove shapes. The grain boundary energy of solid In2Bi phase has been calculated to be (92.8 +/- 10.2) x 10(-3) J m(-2) by considering a force balance at the grain boundary grooves. The thermal conductivities of solid In solution (In-12.4 at.% Bi), solid In2Bi (In-33.2 at.% Bi), the eutectic liquid phase (In-22 at.% Bi) and their ratio at 72 degrees C have also been measured with radial heat flow apparatus and Bridgman type growth apparatus. (C) 2007 Elsevier Inc. All rights reserved.
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    Measurement of solid-liquid interfacial energy in the In-Bi eutectic alloy at low melting temperature
    (IOP PUBLISHING LTD, 2007) Marasli, N.; Akbulut, S.; Ocak, Y.; Keslioglu, K.; Boeyuek, U.; Kaya, H.; Cadirli, E.
    The Gibbs-Thomson coefficient and solid-liquid interfacial energy of the solid In solution in equilibrium with In Bi eutectic liquid have been determined to be (1.46 +/- 0.07) x 10(-7) K m and (40.4 +/- 4.0) x 10(-3) J m(-2) by observing the equilibrated grain boundary groove shapes. The grain boundary energy of the solid In solution phase has been calculated to be (79.0 +/- 8.7) x 10(-3) J m(-2) by considering force balance at the grain boundary grooves. The thermal conductivities of the In-12.4 at.% Bi eutectic liquid phase and the solid In solution phase and their ratio at the eutectic melting temperature (72 degrees C) have also been measured with radial heat flow apparatus and Bridgman-type growth apparatus.
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    The effect of growth rate on microstructure and microindentation hardness in the In-Bi-Sn ternary alloy at low melting point
    (ELSEVIER SCIENCE SA, 2009) Cadirli, E.; Boyuk, U.; Kaya, H.; Marasli, N.; Keslioglu, K.; Akbulut, S.; Ocak, Y.
    In-21.5 at.% Bi-17.8 at.% Sn ternary alloy which has 333 K melting point was directionally solidified upward with a constant temperature gradient (G = 0.91 K/mm) in a wide range of growth rates (3.2-157.1 mu m/s) with a Bridgman type directional solidification furnace. The lamellar spacings (lambda) and microhardness values (H-V) were measured from both transverse and longitudinal sections of the samples. The dependence of lamellar spacings (lambda) and microhardness (H-V) on the growth rate (V) was determined by using linear regression analysis. According to these results, it has been found that the value of lambda decreases with the increasing value of V and whereas, the value of H-V increases for a constant G. The values of lambda V-2 were determined by using the measured values of lambda and V. The results obtained in this work have been compared with the previous similar experimental results obtained for binary or ternary alloys. (C) 2008 Elsevier B.V. All rights reserved.
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    Thermal conductivity and interfacial energies of solid Sn in the Sn-Cu alloy
    (ELSEVIER SCIENCE BV, 2010) Kaygisiz, Y.; Ocak, Y.; Aksoz, S.; Marasli, N.; Keslioglu, K.; Cadirli, E.; Kaya, H.
    The equilibrated grain boundary groove shapes of solid Sn in equilibrium with the Sn-Cu eutectic liquid were observed from a quenched sample. The Gibbs-Thomson coefficient, solid-liquid interfacial energy and grain boundary energy of solid Sn have been determined to be (8.7 +/- 0.6) x 10(-8) Km, (113.1 +/- 13.6) x 10(-3) J m(-2) and (222.4 +/- 28.9) x 10(-3) J m(-2), respectively. The thermal conductivity of solid phase and the thermal conductivity ratio of liquid phase to solid phase for Sn-1.3 at.%Cu alloy have also been measured with radial heat flow apparatus and Bridgman type growth apparatus, respectively. (C) 2009 Elsevier B. V. All rights reserved.