The isothermal section in the Cu-Sn enrich part of the Cu-Sn-Ti ternary system at 823K was determined by using solid-solid-liquid diffusion triple approach. One ternary compound CuSnTi was found, and 12 three-phase fields were detected. The following 10 three-phase regions are well established: CuTi2+CuTi+Sn5Ti6, Sn5Ti6+Sn3Ti2+ CuSnTi, Liquid+Sn3Ti2+CuSnTi, Liquid+CuSnTi+Cu3Sn, CuTi+Cu4Ti3+Sn5Ti6, CuSnTi+Cu4Ti3+Sn5Ti6, CuSnTi+Cu3Sn+Cu41Sn11, CuSnTi+Cu41Sn11+Bcc_a2, CuSnTi+Cu4Ti+Cu, and CuSnTi+Bcc_a2+Cu. Phase relations in the Ti-enrich corner of this system require further investigation.

The Nd-B binary system and Nd-Fe-B ternary system were thermodynamically reassessed with the aim of obtaining more reasonable thermodynamic parameters and more accurate phase relations. Based on the metastable experimental information, a reasonable, self-consistent, and comprehensive thermodynamic description of the Nd-Fe-B ternary system considering the metastable phases Fe3B, Fe23Nd2B3, and Fe17Nd2B has been developed.

The isothermal section of the Co-Ti-V ternary system at 873 K has been investigated by means of diffusion triple together with electron probe microanalysis technique. Series of tie lines and tie-triangles have been determined and the isothermal section at 873 K has been established, and nine three-phase fields have been figured out. It is found that VCo3, VCo, TiCo3, TiCo2(h), TiCo2(c) and TiCo have range of homogeneity at 873 K, and the V3Co and Ti2Co are line compounds. The solid solubility of Ti in VCo3, VCo and V3Co is about 5.2 at.% Ti, 8.8 at.% Ti and 6.9 at.% Ti, and that of V in TiCo3, TiCo2(h), TiCo2(c), TiCo and Ti2Co is about 6.1 at.% V, 3.7 at.% V, 3.0 at.% V, 9.3 at.% V and 6.6 at.% V, respectively. (C) 2014 Elsevier B.V. All rights reserved.

The defrosting is very important in vehicle. In the paper, some improved proposals to the lack performance of the vehicle windshield defrosting would be discussed by using computational fluid dynamic (CFD) numerical simulation analysis and experiment to validate the improved proposal. The improved proposal including change the angle of the grill of wind outlet, and add grill on the left and right side. The discrepancy of the two methods is in 5%, which is acceptable. By the improved proposal that the windshield defrosting area is increased and also the requirements is satisfied.

The effects of heat treatment on morphology of primary α and hardness of B-refined Al-7 wt% Si alloy are investigated. In addition, the optimum heat treatment procedure is also determined. It is shown that, at 450°C with different holding time from 3h to 12h, morphology of primary α phase is converted from irregular dendrite to granular homogeneous equiaxed grains then to rosette structure. The primary α phase is gradually converted from dendrite into the rosette dendrite and then into particle crystal with increasing of temperature by holding 8h at 300~540°C. One can find fine and uniform distributed particle α phase at 400°C or 450°C. However, the primary α phase has changed into large and irregular shape when the temperature increases up to 450°C. The orthogonal analysis shows that the optimum heat treatment parameters are 540±10°Cand 6h.

The effect of the Sr + RE complex modifications on microstructure and mechanical properties of Al-40 wt% Si alloy were investigated. The results show that Sr + RE complex modification not only on primary silicon and eutectic silicon with modification, but also on dendrite α significantly refine. When the addition of RE remain unchanged, with increasing of the addition of Sr, the primary silicon firstly changes from polygonal block or large plate to small block, then to large polygonal block, edge and corner passivations. The eutectic silicon firstly changes into a fine start with a long needle-like fibrous or branched further to a short stubby dendrite or worm-like, The eutectic silicon changes from needle to a fibrous sheet plus short rod, then to short rod end for the dense, or even granular. The dendrite α changes from highly developed dendritic to equiaxed and uniform distribution. In addition, with increasing of the addition of Sr, the mechanical properties has been significantly improved, tensile strength increased by 37%, elongation is more than double, the hardness increased by 21%. When the Sr addition is between 0.05 wt% and 0.077 wt%, the microstructure and mechanical properties are the best.

The effect of Sr on the microstructures and mechanical properties of Al-20 wt% Si alloys were investigated. The results show that with increasing of the Sr content, the primary silicon firstly changes from polygonal block or large plate to small block, then to large polygonal block, and a large number of honeycomb-like on the primary silicon block. The eutectic silicon firstly changes into a fine start with a long needle-like fibrous or branched further to a short stubby dendrite or worm-like, continuously columnar dendrite a of quantity increase. In addition, with increasing the Sr content, the elongation of alloy increases, but there are ups and downs, the tensile strength changes little after the first sharp increases in hardness is parabola. When the Sr content is between 0.04 wt% and 0.06 wt%, the morphology and mechanical properties is the most ideal.

A method, namely the transition rule, for choosing the model of Gibbs free energy difference (ΔG) for metallic glass was proposed. The results show that the ΔG model of metallic glass can be reasonably chosen by the transition from a high ΔG model to a low ΔG model. The transition parameters are the reduced glass transition temperature Trg (=Tg/TL, Tg and TL are the glass transition temperature and liquidus temperature, respectively) and solidification temperature region ΔT (=TL−Tm, Tm is the solidus temperature). The Trg and ΔT values are also determined. In addition, the Trg is a main transition parameter for the eutectic and near-eutectic alloys. The less the ΔT, the stronger is the Trg. Otherwise, the transition is simultaneously controlled by the Trg and ΔT. The transition rule is reliable by the examination of currently available data.

The plate-like powder of Cu60Zr30Ti10 amorphous alloy was prepared by ball milling. The amorphization and deformation mechanisms and thermodynamic properties were also investigated. The powders are milled into plate-like powders and their thicknesses decrease with increasing of milling time. After milling for 184h, the size of the powders decreases down to 250nm and an amorphous structure appears. The average deformation ratio is up to 142, indicating the superplasticity of the powder. The deformation mechanism may be due to a triaxial compressive stress state and/or a suitable temperature field. The amorphization mechanism may result from the diffusion of metal elements by the stress and mechanical energy. In addition, the undercooled liquid region is up to 134K, indicating its better thermodynamic stability.

Pr6O11-doped bismuth titanate (BixPryTi3O12: BPT) thin films with random oriention were fabricated on Pt/Ti/SiO2/Si substrates by rf magnetron sputtering technique, and the structures and ferroelectric properties of the films were investigated. XRD studies indicated that all of BPT films consisted of single phase of a bismuth-layered structure with well-developed rod-like grains. For samples with y=0.06, 0.3, 1.2 and 1.5, ferroelectric hysteresis loops were characterized by large leakage current, whereas for samples with y=0.6 and 0.9, ferroelectric hysteresis loops were the saturated and undistorted hysteresis loops. The remanent polarization ( Pr ) and coercive field (Ec) of the BPT Film with y=0.9 were above 35μC/cm2 and 80KV/cm , respectively. After 3×1010 switching cycles, 20% degradation of 2Pr is observed in the film with y=0.9.

The influence of strontium on the microstructures and mechanical properties of Al-20% Si alloy were investigated. The results show that the primary silicon firstly changes from polygonal block or plate into small block and then big polygonal block, and many cellular points distribute on the flake. With increase of strontium content, the edge of the primary silicon becomes blunt. The eutectic silicon changes from long thin needle-shape into short fibrous or dendrite at first and then into worm-like. The α-Al dendrite is becoming columnar and the number is increased. On the other hand, the elongation of the alloy increases gradually, but with fluctuation, the tensile strength firstly increases sharply then no more varies, and the hardness changes according to a parabolic curve. When the content of strontium varies from 0.04wt% to 0.06wt%, the microstructures and the comprehensive mechanical properties are optimal. The tensile strength and hardness are enhanced nearly three times and the ductility five times.

In present work, the characteristics of three methods such as the orthogonal design, Fuzzy optimum method and artificial neural network modeling technique were made on the basis of the optimization and evaluation of the performance of the phosphate graphite mold. The variance analysis indicates that the phosphoric acid has greatest influence on both compression strength and tension strength of phosphate graphite mold, both drying temperature and drying time greater, and Al2O3 minor, respectively. The Fuzzy multi-objective comprehensive evaluation shows that the optimum technology for phosphate graphite mold designed by us is phosphoric acid 30%, Al2O3 30%, drying temperature 400°C and drying time 60min. In addition, the ANN can be used to establish mono- and multi-objective models for the prediction of other tests outside orthogonal test with rather high accuracy. However, the predicted results are worse for the linear regressive equations by the orthogonal analysis.

We propose expressions for the estimation of the isenthalpic temperature T 0 (T 0 = αT m , α is a semi-empirical parameter and 0 ⩽ α < 1, T m is the solidus temperature) and the Kauzmann temperature T k (T k = T m exp(α−1)) for glass forming alloys. It is found that T k estimated by T k = T m exp(α−1) is in agreement with that directly calculated from the heat capacity data, indicating that T k = T m exp(α − 1) can be used to estimate T k of glass forming alloys. T 0 estimated by T 0 = αT m , on the other hand, widely deviates from that of directly calculated from the heat capacity data. This suggests that the enthalpy difference of the under-cooled liquid and the crystal might be a nonlinear function of the temperature below T k . Moreover, the Gibbs free energy difference ΔG is not sensitive to the deviation of α.

In present work, the compression strength and tensile strength of phosphate graphite sand with compositional and technological parameters (phosphoric acid, Al2O3, drying temperature, and drying time) were experimentally investigated. An L9 (34) orthogonal array was employed to analyze the effect of these four parameters on the compression strength and tensile strength, respectively. In addition, the radial basis function artificial neural network (RBFANN) was used to establish the models for compression strength and tensile strength, respectively. Moreover, the simulation and prediction results by the RBFANN and linear and non-linear regressions are compared. The results are as follows: the optimum scheme for phosphate graphite sand designed by us is phosphoric acid 24%, Al2O3 30%, drying temperature 400 °C, and drying time 60 min. The ascending sequence of the effect of four factors on both compression strength and tensile strength of phosphate graphite sand is drying time, drying temperature, Al2O3, and phosphoric acid. In addition, the prediction and simulation results show that RBFANN outperforms Taguchi approach for modeling.

In present work, we researched the relationships between ΔHm and critical cooling rate Rc of five bulk metallic glass (BMG) systems, such as Mg–Ni–Nd, Pd–Cu–Si, La–Al–Ni–Cu, Zr–Al–Ni–Cu and Zr–Ti–Ni–Cu–Be, respectively, and five Zr–Al–Ni–Cu bulk metallic glasses with critical dimension Zmax up to Ø7.5 mm are also developed by us in the light of the optimum ΔHm of Zr–Al–Ni–Cu alloy system. The results show that the relationships between ΔHm and Rc are all concave upward parabolas, and the optimum ΔHms for Mg–Ni–Nd, Pd–Cu–Si, Zr–Al–Ni–Cu, Zr–Ti–Ni–Cu–Be and La–Al–Ni–Cu are 10.3960, 21.2202, 19.7146, 18.1455 and 13.1558 KJ mol−1, respectively. Furthermore, other BMG’ Rcs predicted by above-mentioned relationships satisfactorily agree with the tested results, which indicates that these relationships are reliable. However, the predicted results are reliable only if the main components are similar with the fitted BMG system or the additive is sparkle enough that the alloy's characteristic is not changed. On the whole, the ΔHm can be used for quickly predicting the alloy's GFA and helpful for the development of new BMGs.

One of the important problems for materials science is the thermodynamics of solidification and nucleation. The derivation procedure of the formulae relating to consolidation and nucleation thermodynamics for liquid metals in some teaching materials was analyzed in this paper. It is found that there is dimensional heterogeneity of some parameters, resulting in the wrong results. By unifying the dimension of parameters, the corrective relationship of the critical diameter of crystal nucleus for homogeneous nucleation is obtained. And its validation is examined by practical example. The results show that the corrective relationship of the critical diameter of crystal nucleus for homogeneous nucleation is reliable.

A new melting enthalpy ΔHm criterion for the prediction of glass forming ability (GFA) of alloys is proposed and five Zr–Al–Ni–Cu bulk metallic glasses (BMG) with critical dimension Zmax up to ∅ 7.5mm are also developed by us in the light of the optimum ΔHm of Zr–Al–Ni–Cu alloy system. And then, we researched the relationships between ΔHm and two GFA parameters (critical cooling rate Rc and Zmax) of five bulk metallic glass (BMG) systems, such as Mg–Ni–Nd, Pd–Cu–Si, La–Al–Ni–Cu, Zr–Al–Ni–Cu and Zr–Ti–Ni–Cu–Be, respectively. The results show that the relationships between ΔHm and Rc are all concave upward parabolas, and the optimum ΔHms for Mg–Ni–Nd, Pd–Cu–Si, Zr–Al–Ni–Cu, Zr–Ti–Ni–Cu–Be and La–Al–Ni–Cu are 10.3960kJmol−1, 21.2202kJmol−1, 19.7146kJmol−1, 18.1455kJmol−1 and 13.1558kJmol−1, respectively. On the contrary, the relationships between ΔHm and Zmax are all concave downward parabolas, and the optimum ΔHms for Mg–Ni–Nd, Pd–Cu–Si, Zr–Al–Ni–Cu, Zr–Ti–Ni–Cu–Be and La–Al–Ni–Cu are 10.5530kJmol−1, 21.0830kJmol−1, 19.6603kJmol−1, 19.7231kJmol−1 and 13.1173kJmol−1, respectively. Furthermore, other BMGs’ Rcs or Zmaxs predicted by above-mentioned relationships satisfactorily agree with the tested results, which indicates that these relationships are reliable. However, the predicted results are reliable only if the main components are similar with the fitted BMGs or the additive is sparkle enough that the alloy’s character does not change. On the whole, the ΔHm can act as a criterion for quickly predicting the alloy’s GFA and be helpful for the development of new BMGs.

In present work, the difference among orthogonal design, Fuzzy optimum design and artificial neural network ANN was performed on the basis of the optimization of chemical composition of chromium white cast iron. It is found that Fuzzy optimum design is suitable for multi-objective comprehensive evaluation, and the optimum composition of white cast iron is Cr 4%, Si 3.5%, Mn 3% and Cu 1% in the orthogonal array. On the other hand, the orthogonal analysis is suitable for analyzing the effect of each factor on the performances and obtaining the theoretical optimum combination of each factor for the performances and the optimum theoretical performances, respectively. Moreover, the prediction and simulation results show that the RBFANN not only can be used to establish the model with high accuracy for the orthogonal test but also outperforms the traditional orthogonal analysis method. Therefore, the combination of three methods can more effectively deal with the optimization of chemical composition of materials.

We propose an expression, Delta G = Delta H-m[{alpha(T-T-m)/(1-alpha)T-m}+{T/(1-alpha)T-m}ln(T-m/T)] (O < a < 1), for the calculation of Gibbs free energy difference Delta G of multi-component metallic alloys. The results show that the theoretical Delta Gs are in better agreement with the experimental values over entire under-cooling range than those given by the TS, KN1 and KN2 expressions. The glass-forming ability of the multi-component metallic alloys has been observed to increase with the increase in the difference of the glass transition temperature and isenthalpic temperature. (c) 2006 Elsevier B.V. All rights reserved.

A newly derived expression for estimation of Gibbs free energy difference (ΔG) between the crystalline and under-cooled liquid of glass-forming alloys have been utilized to obtain theoretical ΔG for a variety of alloy systems. It gives better results nearly overlapping with the experimental values over entire under-cooling region for all alloy systems studied in this paper. However, the theoretical results given by other expressions deviate from the experimental values even in small under-cooling region except that the expressions proposed by Thompson and Spaepen and Lad et al. give a close estimation to the experimental ΔG in the temperature region of 680–937K for Zr41.2Ti13.8Ni10Cu12.5Be22.5 and 450–662K for La55Cu10Ni10Al25, respectively. In addition, the results in present work will provide us with the evidence of the choice of the α values for different metallic glasses.