The Experts below are selected from a list of 1422 Experts worldwide ranked by ideXlab platform
Jingjie Guo - One of the best experts on this subject based on the ideXlab platform.
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effects and mechanism of ultrasonic irradiation on solidification microstructure and mechanical properties of binary tial alloys
Ultrasonics Sonochemistry, 2017Co-Authors: Ruirun Chen, Hongsheng Ding, Deshuang Zheng, Jingjie GuoAbstract:Abstract In spite of their high temperature and reactivity, the binary TiAl alloys are successfully imposed by the ultrasonic irradiation and the microstructure evolution, solidification behaviors and mechanical properties are elaborately investigated. After ultrasonic irradiation, a high quality ingot without shrinkage defects and element segregation is obtained and the coarse dendrite structure is well modified into fine non-dendrite globular grains. The coarse lamellar colony and lamellar space of Ti44Al alloy is refined from 685 μm to 52 μm and 1185 nm to 312 nm, respectively (similarly, 819 μm to 102 μm and 2085 nm to 565 nm for Ti48Al alloy). For Ti48Al alloy, the α Peritectic phase is simultaneously precipitated from the melt as well as the β primary phase before the Peritectic Reaction and the solidification is transformed into the mixed α-solidifying and β-solidifying. Ultrasonic irradiation promotes the Peritectic Reaction and phase transformation completely and the phase constituent becomes more close to the equilibrium level. The compressive strength of Ti44Al and Ti48Al alloys are increased from 623 MPa to 1250 MPa and 980 MPa to 1295 MPa, respectively. The grain refinement and dendrite transformation enhance the grain boundary sliding improving the plastic deformation ability. Ultrasonic irradiation significantly accelerates the melt flow and solute redistribution and the main grain refinement mechanism is the cavitation-enhanced nucleation by inclusion activation and heightened supercooling.
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rapid cellular crystal growth of tial based intermetallic without Peritectic Reaction by melt quenching in ga in liquid
Crystal Growth & Design, 2017Co-Authors: Shiqiu Liu, Hongsheng Ding, Jingjie Guo, Hailong Zhang, Zhanxing Chen, Qiang Wang, Ruirun ChenAbstract:A rapid cellular microstructure of Ti-48Al-2Cr-2Nb (in atom %) intermetallic was grown without Peritectic Reaction by the method of melt-quenching in Ga–In liquid. After characterization of the microstructures and phase constituents, it is observed that the cellular crystals mainly consist of the α2 phase and directionally grew in the outer layer of the melt droplet, with the growth length and cellular spacing about 358–460 μm and 0.68–3.6 μm, respectively. Upon detailed analysis of the cellular growth process, it is found that the formation of this characteristic microstructure is derived from the extremely rapid cooling effect of Ga–In liquid, mainly determined by the heat transfer process; the dominant heat transfer mechanism changes from heat convection to heat conduction at a growth distance of about 70 μm. By using the semireverse method, the dependence of the cooling rate on the cellular growth distance can be estimated accurately and conveniently, which ranges from 2.61 × 106 to 1.26 × 105 K/s. Th...
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a lateral remelting phenomenon of the primary phase below the temperature of Peritectic Reaction in directionally solidified cu ge alloys
Journal of Materials Research, 2013Co-Authors: Shujie Wang, Liangshun Luo, Jingjie GuoAbstract:During Peritectic solidification, besides the longitudinal remelting of the primary phase at the temperature of Peritectic Reaction $$\left( {T_{\rm{p}}^K} \right)$$ , a lateral remelting phenomenon of the primary phase below $$T_{\rm{p}}^K$$ is observed under high velocity in directionally solidified Cu–Ge alloys. The lateral remelting occurs continuously along a liquid channel as temperature decreases, and the lateral remelting velocity is larger than that of Peritectic transformation. The lateral remelting leads to the morphological change of the primary dendrites, even the fragmentation of dendrite arms. The phenomenon also means that the classical theory calculating the volume fraction of the primary phase during Peritectic transformation can need to be modified under some conditions. However, under low velocity, the phenomenon is not so significant. The phenomenon is explained by means of solidification and remelting theory.
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two phase separated growth and Peritectic Reaction during directional solidification of cu ge Peritectic alloys
Journal of Materials Research, 2013Co-Authors: Shujie Wang, Fuyu Dong, Liangshun Luo, Jingjie GuoAbstract:During directional solidification of Cu–Ge Peritectic alloys, a two-phase separated structure has been observed. With proper growth conditions, the Peritectic ζ-Cu5Ge and primary α-Cu phases completely separate and form cylindrical layered structures. It is found that the formation of the separated structure is closely related to double diffusive convection and growth conditions. In the two-phase separated structure, a large trijunction region of Peritectic Reaction forms around the cylindrical α-Cu phase. During Peritectic Reaction, the morphological instabilities of ζ-Cu5Ge occur under high pulling velocities and are explained by the constitutional undercooling criterion. A new coupling growth between the ζ-Cu5Ge-phase and the groove of α-Cu phase near the trijunction is observed. Different from Peritectic coupling growth, the diffusion coupling is established below the Peritectic temperature. This two-phase separated growth process creates new opportunities for the fabrication of functionally layered materials.
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effect of Peritectic Reaction on the migration of secondary dendrite arms in the presence of tertiary dendrites analysis of a directionally solidified sn 36 at ni Peritectic alloy
Journal of Materials Science, 2013Co-Authors: Peng Peng, Dongmei Liu, Jingjie GuoAbstract:Directional solidification experiments have been performed on Sn–36 at.%Ni Peritectic alloy in a constant temperature gradient at different growth velocities. Experimental result shows that a “sawtooth” morphology forms on secondary dendrite arms during the migration of secondary dendrites in the presence of tertiary dendrite arms. A theoretic model is therefore proposed to describe the formation of this “sawtooth” morphology in the Peritectic solidification with tertiary dendrite arms taken into consideration. The migration of secondary dendrite arms is caused by remelting/solidification at the hot/cold sides of a liquid pool between secondary dendrite arms, which is a form of temperature gradient zone melting. And, the “sawtooth” morphology is ascribed to the difference in remelting velocity at the hot side of liquid pool during the migration of secondary dendrite arms due to the presence of tertiary dendrite arms. In addition, the proceeding of Peritectic Reaction can accelerate the formation of “sawtooth” morphology.
Peng Peng - One of the best experts on this subject based on the ideXlab platform.
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investigation on morphology evolution of secondary branch during Peritectic solidification in a temperature gradient through morphology characteristic experimental measurement and prediction
Materials Chemistry and Physics, 2020Co-Authors: Jinmian Yue, Anqiao Zhang, Xudong Zhang, Peng Peng, Jieren YangAbstract:Abstract Despite the obvious influence of the secondary branch on final microstructure and properties of alloy, investigation on the morphology variation of it during solidification is not enough. On the basis of a parameter ϕ, the morphology evolution of it during Peritectic solidification was analyzed. Experimental measurements on two Peritectic alloys: Sn–Ni and Sn–Mn show that ϕ first decreases then turns to increase with solidification time. The minimum of ϕ during Peritectic solidification is found after Peritectic Reaction. Further examination shows that ϕ first decrease because it is mainly determined by the growth of secondary branch before Peritectic Reaction. Then, it is mainly dependent on the radius of secondary branches since the growth space for them is obviously restricted after Peritectic Reaction. Further analysis shows that the continuous increase of ϕ with solidification time after Peritectic Reaction is caused by the remelting/resolidification process by both the Gibbs-Thomson (G-T) and temperature gradient zone melting (TGZM) effects on secondary branch. It was also confirmed that the remelting/resolidification process by the G-T effect is less important as compared with that by the TGZM effect. As a result, resolidification on both the front and back edges of thicker secondary branches leads to the “V”-type variation of ϕ during Peritectic solidification. The analytical prediction in which the influences of these effects are taken into account shows reasonably agreement with the experimental measurement.
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restriction or acceleration investigation on the remelting resolidification process during sn ni Peritectic solidification in a temperature gradient
Journal of Alloys and Compounds, 2020Co-Authors: Peng PengAbstract:Abstract In this work, extensive remelting/resolidification process induced by diffusion on the secondary dendrite arms in the mushy zone was confirmed in a Sn–Ni Peritectic alloy. Examination on the dependence of λ2 on local solidification time showed that the remelting/resolidification process on secondary dendrite arm by the Gibbs-Thomson effect was restricted at the initial of Peritectic Reaction. Then, this restriction turns to disappear as directional solidification proceeds. Experimental observation shows that the remelting/resolidification on secondary dendrite arm could be attributed to both the Gibbs-Thomson and temperature gradient zone melting (TGZM) effect. Further analysis showed that this remelting/resolidification process was complicated in Peritectic alloys due to interaction between Peritectic Reaction and the TGZM effect by the imposed temperature gradient. It was found that the influence of Peritectic Reaction on the remelting/resolidification process was different at different stages of solidification. The restriction or acceleration of the Gibbs-Thomson effect by Peritectic Reaction at different stages of solidification was clarified by diffusion-controlled analytical model describing the remelting/resolidification process. The dependence of the remelting/resolidification process on secondary dendrite arm on solidification time can be attributed to the interaction between Peritectic Reaction, the Gibbs-Thomson and TGZM effects.
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effect of Peritectic Reaction on the migration of secondary dendrite arms in the presence of tertiary dendrites analysis of a directionally solidified sn 36 at ni Peritectic alloy
Journal of Materials Science, 2013Co-Authors: Peng Peng, Dongmei Liu, Jingjie GuoAbstract:Directional solidification experiments have been performed on Sn–36 at.%Ni Peritectic alloy in a constant temperature gradient at different growth velocities. Experimental result shows that a “sawtooth” morphology forms on secondary dendrite arms during the migration of secondary dendrites in the presence of tertiary dendrite arms. A theoretic model is therefore proposed to describe the formation of this “sawtooth” morphology in the Peritectic solidification with tertiary dendrite arms taken into consideration. The migration of secondary dendrite arms is caused by remelting/solidification at the hot/cold sides of a liquid pool between secondary dendrite arms, which is a form of temperature gradient zone melting. And, the “sawtooth” morphology is ascribed to the difference in remelting velocity at the hot side of liquid pool during the migration of secondary dendrite arms due to the presence of tertiary dendrite arms. In addition, the proceeding of Peritectic Reaction can accelerate the formation of “sawtooth” morphology.
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effect of Peritectic Reaction on dendrite coarsening in directionally solidified sn 36 at ni alloy
Journal of Materials Science, 2012Co-Authors: Peng Peng, Dongmei Liu, Jingjie GuoAbstract:Effect of Peritectic Reaction on dendrite coarsening was investigated in directionally solidified Sn–36 at.%Ni Peritectic alloys at different growth rates (2~200 μm/s) under constant temperature gradient. A coarsening model was used to characterize the coarsening process in terms of both the secondary dendrite arm spacing (λ 2) of the primary Ni3Sn2 phase and the specific surface area (S V ) of dendrites. It was shown that Peritectic Reaction could retard the increase of λ 2 and decrease of S V during coarsening, which resulted from decelerating solute transport rate between adjacent dendrite arms caused by the Peritectic phase enclosing the primary phase. The kinetics of the Peritectic Reaction that was found to be crucial to determine the coarsening process was characterized by the Reaction constant (f) which not only changed with growth rates but also with solidification time in the real solidification process at a given growth rate.
Xudong Zhang - One of the best experts on this subject based on the ideXlab platform.
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macrosegregation and thermosolutal convection induced freckle formation in dendritic mushy zone of directionally solidified sn ni Peritectic alloy
Journal of Materials Science & Technology, 2021Co-Authors: Anqiao Zhang, Jinmian Yue, Xudong ZhangAbstract:Abstract Compared with the growing applications of Peritectic alloy, none research on the freckle formation during Peritectic solidification has been reported before. Observation on the dendritic mushy zone of Sn-36 at.%Ni Peritectic alloy during directional solidification at different growth velocities shows that the freckles are formed in two different regions: region I before Peritectic Reaction and region II after Peritectic Reaction. In addition, more freckles can be observed at lower growth velocities. Examination on the experimental results demonstrates that both the temperature gradient zone melting (TGZM) and Gibbs-Thomson (G–T) effects have obvious influences on the morphology of dendritic network during directional solidification. The current theories onKI Rayleigh number Ra characterizing the thermosolutal convection of dendritic mushy zone to predict freckle formation through the maximum of Ra can only explain the existence of region I while the appearance of region II after Peritectic Reaction cannot be predicted. Thus, a new Rayleigh number RaP is proposed in consideration of evolution of dendritic mushy zone by both effects and Peritectic Reaction. Theoretical prediction of RaP also shows a maximum after Peritectic Reaction in addition to that before Peritectic Reaction, thus, agreeing well with the freckle formation in region II. In addition, more severe thermosolutal convection can be predicted by the new Rayleigh number RaP at lower growth velocities, which further demonstrates the reliability of RaP in describing the dependence of freckle formation on growth velocity.
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investigation on morphology evolution of secondary branch during Peritectic solidification in a temperature gradient through morphology characteristic experimental measurement and prediction
Materials Chemistry and Physics, 2020Co-Authors: Jinmian Yue, Anqiao Zhang, Xudong Zhang, Peng Peng, Jieren YangAbstract:Abstract Despite the obvious influence of the secondary branch on final microstructure and properties of alloy, investigation on the morphology variation of it during solidification is not enough. On the basis of a parameter ϕ, the morphology evolution of it during Peritectic solidification was analyzed. Experimental measurements on two Peritectic alloys: Sn–Ni and Sn–Mn show that ϕ first decreases then turns to increase with solidification time. The minimum of ϕ during Peritectic solidification is found after Peritectic Reaction. Further examination shows that ϕ first decrease because it is mainly determined by the growth of secondary branch before Peritectic Reaction. Then, it is mainly dependent on the radius of secondary branches since the growth space for them is obviously restricted after Peritectic Reaction. Further analysis shows that the continuous increase of ϕ with solidification time after Peritectic Reaction is caused by the remelting/resolidification process by both the Gibbs-Thomson (G-T) and temperature gradient zone melting (TGZM) effects on secondary branch. It was also confirmed that the remelting/resolidification process by the G-T effect is less important as compared with that by the TGZM effect. As a result, resolidification on both the front and back edges of thicker secondary branches leads to the “V”-type variation of ϕ during Peritectic solidification. The analytical prediction in which the influences of these effects are taken into account shows reasonably agreement with the experimental measurement.
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Analysis on fluid permeability of dendritic mushy zone during Peritectic solidification in a temperature gradient
Journal of Materials Science & Technology, 2026Co-Authors: Jinmian Yue, Anqiao Zhang, Xudong ZhangAbstract:Abstract Compared with the growing applications of Peritectic alloys, none research on the fluid permeability K of dendritic network during Peritectic solidification has been reported before. The fluid permeability K of dendritic network in the mushy zone during directional solidification of Sn-Ni Peritectic alloy was investigated in this study. Examination on the experimental results demonstrates that both the temperature gradient zone melting (TGZM) and Gibbs-Thomson (G–T) effects have obvious influences on the morphology of dendritic network during directional solidification. This is realized through different stages of liquid diffusion within dendritic mushy zone by these effects during directional solidification. The TGZM effect is demonstrated to play a more important role as compared with the G–T effect during directional solidification. Besides, it is shown that the evolution of dendrite network is more complex during Peritectic solidification due to the involvement of the Peritectic phase. Through the specific surface SV, analytical expression based on the Carman–Kozeny model was proposed to analyze the fluid permeability of dendritic mushy zone in directionally solidified Peritectic alloys. In addition, it is interesting to find a rise in permeability K after Peritectic Reaction in both theoretical predication and experimental results, which is different from that in other alloys. The theoretical predictions show that this rise in fluid permeability K after Peritectic Reaction is caused by the remelting/resolidification process on dendritic structure by the TGZM and G–T effects during Peritectic solidification.
Liangshun Luo - One of the best experts on this subject based on the ideXlab platform.
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a lateral remelting phenomenon of the primary phase below the temperature of Peritectic Reaction in directionally solidified cu ge alloys
Journal of Materials Research, 2013Co-Authors: Shujie Wang, Liangshun Luo, Jingjie GuoAbstract:During Peritectic solidification, besides the longitudinal remelting of the primary phase at the temperature of Peritectic Reaction $$\left( {T_{\rm{p}}^K} \right)$$ , a lateral remelting phenomenon of the primary phase below $$T_{\rm{p}}^K$$ is observed under high velocity in directionally solidified Cu–Ge alloys. The lateral remelting occurs continuously along a liquid channel as temperature decreases, and the lateral remelting velocity is larger than that of Peritectic transformation. The lateral remelting leads to the morphological change of the primary dendrites, even the fragmentation of dendrite arms. The phenomenon also means that the classical theory calculating the volume fraction of the primary phase during Peritectic transformation can need to be modified under some conditions. However, under low velocity, the phenomenon is not so significant. The phenomenon is explained by means of solidification and remelting theory.
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two phase separated growth and Peritectic Reaction during directional solidification of cu ge Peritectic alloys
Journal of Materials Research, 2013Co-Authors: Shujie Wang, Fuyu Dong, Liangshun Luo, Jingjie GuoAbstract:During directional solidification of Cu–Ge Peritectic alloys, a two-phase separated structure has been observed. With proper growth conditions, the Peritectic ζ-Cu5Ge and primary α-Cu phases completely separate and form cylindrical layered structures. It is found that the formation of the separated structure is closely related to double diffusive convection and growth conditions. In the two-phase separated structure, a large trijunction region of Peritectic Reaction forms around the cylindrical α-Cu phase. During Peritectic Reaction, the morphological instabilities of ζ-Cu5Ge occur under high pulling velocities and are explained by the constitutional undercooling criterion. A new coupling growth between the ζ-Cu5Ge-phase and the groove of α-Cu phase near the trijunction is observed. Different from Peritectic coupling growth, the diffusion coupling is established below the Peritectic temperature. This two-phase separated growth process creates new opportunities for the fabrication of functionally layered materials.
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morphological characteristics of triple junction region and process of the Peritectic Reaction during directional solidification of cu ge alloys
Journal of Alloys and Compounds, 2012Co-Authors: Shujie Wang, Liangshun Luo, Jinchuan Jie, Jingjie GuoAbstract:Abstract A huge triple phase region of the nonfaceted–nonfaceted Peritectic Reaction within a large temperature region (around 8 K) was obtained in directionally solidified Cu–Ge alloys, which provides a convincing experimental evidence for studying the morphology of Peritectic Reaction trijunction region. The huge non-isothermal triple phase region suggests that the Peritectic Reaction occurs in a composition range, which is different from the classic isothermal model with a fixed composition (Liquid + solid solution α (CuGe 12 ) → solid solution ζ (CuGe 12.8 )). The geometrical morphology of triple junction region shows that the primary α phase remelted ahead of the growing Peritectic phase and resolidified near the triple phase junction. And some new characteristics of the Peritectic Reaction were also observed and systematically analyzed. The results demonstrate that the Peritectic Reaction during directional solidification occurs in the style: Liquid + remelted α (CuGe (12∼12− x ) ) → ζ (CuGe (12.8–12.8+ y ) ) + resolidified α (CuGe 12 ) . The x and y depend on growth conditions and alloy composition. The remelting and resolidification phenomenon were discussed in detail, in which the effects of temperature gradient, mechanical equilibrium and solute diffusion were considered. Orientation relationship between the phases was studied by the electron back-scatter diffraction (EBSD) technology.
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Peritectic Reaction and its influences on the microstructures evolution during directional solidification of fe ni alloys
Journal of Alloys and Compounds, 2008Co-Authors: Liangshun Luo, Jingjie Guo, Hong Zhong, L LiuAbstract:Abstract Systematic directional solidification experiments were carried out in Fe–Ni Peritectic alloys to investigate the influences of Peritectic Reaction on the microstructures evolution. Various microstructures were observed in the directionally solidified samples, such as bands, mixed bands, island banding, tree-like oscillatory pattern, coupled and cellular coupled growth structures. It was found that Peritectic Reaction occurs near the trijunctions during the two-phase growth at different interface morphologies of the primary phase observed as planar, cellular and dendritic. Peritectic Reaction makes the liquid/δ/γ trijunctions region quite irregular and makes the trijunctions dynamics quite complicated, and thus plays an important role in the formation of various microstructures.
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a simple model for lamellar Peritectic coupled growth with Peritectic Reaction
Science China-physics Mechanics & Astronomy, 2007Co-Authors: Liangshun Luo, Jingjie GuoAbstract:The lamellar Peritectic coupled growth in Fe-Ni Peritectic system was investigated using the equilibrium Boettinger-Jackson-Hunt model. It was found that the slope of the undercooling vs. lamellar spacing is very near zero around the minimum overheating, and the coupled growth can exist under this condition even if the slope of the undercooling vs. lamellar spacing curve is slightly smaller than zero. In addition, the Peritectic Reaction can never reach completion during the Peritectic coupled growth. So the equilibrium Peritectic coupled growth was modified by considering the incompletion of the Peritectic Reaction. It was shown that when the fractions of the Peritectic Reaction reach 60%–80% completion, the calculated undercooling vs. lamellar spacing curves agree well with the experimental observations in the directionally solidified Fe-Ni alloys.
Shujie Wang - One of the best experts on this subject based on the ideXlab platform.
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Stability of remelting and solidification interfaces of triple-phase region during Peritectic Reaction at lower speed
Transactions of Nonferrous Metals Society of China, 2014Co-Authors: Shujie Wang, Fuyu Dong, Su Yanqing, Liang Wang, F U HengzhiAbstract:Abstract Peritectic Reaction was studied by directional solidification of Cu-Ge alloys. A larger triple junction region of Peritectic Reaction was used to analyze the interface stability of the triple junction region during Peritectic Reaction. Under different growth conditions and compositions, different growth morphologies of triple junction region are presented. For the hypoPeritectic Cu-13.5%Ge alloy, as the pulling velocity ( v ) increases from 2 to 5 μm/s, the morphological instability of the Peritectic phase occurs during the Peritectic Reaction and the remelting interface of the primary phase is relatively stable. However, for the hyperPeritectic Cu-15.6%Ge alloy with v =5 μm/s, the nonplanar remelting interface near the trijunction is presented. The morphological stabilities of the solidifying Peritectic phase and the remelting primary phase are analyzed in terms of the constitutional undercooling criterion.
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a lateral remelting phenomenon of the primary phase below the temperature of Peritectic Reaction in directionally solidified cu ge alloys
Journal of Materials Research, 2013Co-Authors: Shujie Wang, Liangshun Luo, Jingjie GuoAbstract:During Peritectic solidification, besides the longitudinal remelting of the primary phase at the temperature of Peritectic Reaction $$\left( {T_{\rm{p}}^K} \right)$$ , a lateral remelting phenomenon of the primary phase below $$T_{\rm{p}}^K$$ is observed under high velocity in directionally solidified Cu–Ge alloys. The lateral remelting occurs continuously along a liquid channel as temperature decreases, and the lateral remelting velocity is larger than that of Peritectic transformation. The lateral remelting leads to the morphological change of the primary dendrites, even the fragmentation of dendrite arms. The phenomenon also means that the classical theory calculating the volume fraction of the primary phase during Peritectic transformation can need to be modified under some conditions. However, under low velocity, the phenomenon is not so significant. The phenomenon is explained by means of solidification and remelting theory.
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two phase separated growth and Peritectic Reaction during directional solidification of cu ge Peritectic alloys
Journal of Materials Research, 2013Co-Authors: Shujie Wang, Fuyu Dong, Liangshun Luo, Jingjie GuoAbstract:During directional solidification of Cu–Ge Peritectic alloys, a two-phase separated structure has been observed. With proper growth conditions, the Peritectic ζ-Cu5Ge and primary α-Cu phases completely separate and form cylindrical layered structures. It is found that the formation of the separated structure is closely related to double diffusive convection and growth conditions. In the two-phase separated structure, a large trijunction region of Peritectic Reaction forms around the cylindrical α-Cu phase. During Peritectic Reaction, the morphological instabilities of ζ-Cu5Ge occur under high pulling velocities and are explained by the constitutional undercooling criterion. A new coupling growth between the ζ-Cu5Ge-phase and the groove of α-Cu phase near the trijunction is observed. Different from Peritectic coupling growth, the diffusion coupling is established below the Peritectic temperature. This two-phase separated growth process creates new opportunities for the fabrication of functionally layered materials.
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morphological characteristics of triple junction region and process of the Peritectic Reaction during directional solidification of cu ge alloys
Journal of Alloys and Compounds, 2012Co-Authors: Shujie Wang, Liangshun Luo, Jinchuan Jie, Jingjie GuoAbstract:Abstract A huge triple phase region of the nonfaceted–nonfaceted Peritectic Reaction within a large temperature region (around 8 K) was obtained in directionally solidified Cu–Ge alloys, which provides a convincing experimental evidence for studying the morphology of Peritectic Reaction trijunction region. The huge non-isothermal triple phase region suggests that the Peritectic Reaction occurs in a composition range, which is different from the classic isothermal model with a fixed composition (Liquid + solid solution α (CuGe 12 ) → solid solution ζ (CuGe 12.8 )). The geometrical morphology of triple junction region shows that the primary α phase remelted ahead of the growing Peritectic phase and resolidified near the triple phase junction. And some new characteristics of the Peritectic Reaction were also observed and systematically analyzed. The results demonstrate that the Peritectic Reaction during directional solidification occurs in the style: Liquid + remelted α (CuGe (12∼12− x ) ) → ζ (CuGe (12.8–12.8+ y ) ) + resolidified α (CuGe 12 ) . The x and y depend on growth conditions and alloy composition. The remelting and resolidification phenomenon were discussed in detail, in which the effects of temperature gradient, mechanical equilibrium and solute diffusion were considered. Orientation relationship between the phases was studied by the electron back-scatter diffraction (EBSD) technology.