The diagram of Ag-Cu-Ge system was constructed from the investigation of 13 internal sec- tions by DTA heating as well as cooling curves in an atomsphere of dry N_2 . The phase dia- gram is subdivided into two pseudo-...The diagram of Ag-Cu-Ge system was constructed from the investigation of 13 internal sec- tions by DTA heating as well as cooling curves in an atomsphere of dry N_2 . The phase dia- gram is subdivided into two pseudo-ternary systems shown as Ag-Cu-Cu_3Ge and Ag-Cu_3Ge-Ge. Both systems belong to simple eutectic type. The ternary eutectic points lie in.' E_1, Ag(22.0)-Cu(58.8)-Ge(19.2), 632℃ and E_2 , Ag(44.3)-Cu(29.5)-Ge(26.2), 533℃. The three side binary systems were redetermined.展开更多
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 per...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 wim 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.展开更多
对添加少量合金元素Cu和Ge的Zr-4+xCu+xGe(x=0、0.05、0.1、0.2,质量分数,%)合金在360℃/18.6 MPa/0.01 M LiOH水溶液中进行静态高压釜腐蚀试验。利用TEM和SEM研究了合金和氧化膜的显微组织。结果表明:添加适量Cu和Ge可以延缓氧化膜中...对添加少量合金元素Cu和Ge的Zr-4+xCu+xGe(x=0、0.05、0.1、0.2,质量分数,%)合金在360℃/18.6 MPa/0.01 M LiOH水溶液中进行静态高压釜腐蚀试验。利用TEM和SEM研究了合金和氧化膜的显微组织。结果表明:添加适量Cu和Ge可以延缓氧化膜中微裂纹的形成,显著提高Zr-4合金在360℃/18.6 MPa/0.01 M LiOH水溶液中的耐腐蚀性能;在Zr-4+xCu+xGe合金中主要析出密排六方结构的Zr(Fe,Cr)_2和Zr(Fe,Cr,Cu,Ge)_2型第二相,随着Cu和Ge添加量的进一步提高,还会有粗大的四方结构的Zr_2Cu和Zr_3Ge第二相析出,第二相的氧化易导致应力集中并促进微裂纹形成,不利于Zr-4合金耐腐蚀性能的改善。展开更多
The Sn-Cu-Ni-Ge solder is a strong challenger to the Sn-Ag-Cu(SAC) solders as a replacement for the Sn-Pb eutectic solder. This research investigated the effects of addition of Ag, Bi, In, and Sb on the physical pro...The Sn-Cu-Ni-Ge solder is a strong challenger to the Sn-Ag-Cu(SAC) solders as a replacement for the Sn-Pb eutectic solder. This research investigated the effects of addition of Ag, Bi, In, and Sb on the physical properties of the Sn-0.6 Cu-0.05 Ni-Ge(SCNG) lead-free solder and the interfacial reaction with the Cu substrate. The melting behavior, microstructure, tensile strength, and wettability of the SCNG-x(x=Ag, Bi, In, Sb) solders were examined. The findings revealed that the introduction of Ag, Bi, In, and Sb minimally altered the solidus temperature, liquidus temperature, and tensile strength of the solder. However, the cooling behavior and solidified microstructure of the solder were affected by the concentration of the alloying elements. The wettability of the SCNG solder was improved with the doping of the alloying elements except Sb. The thickness of intermetallic layer was increased by the addition of the alloying elements and was related to the cooling behavior of the solder. The morphology of intermetallic layer between the SCNG-x solders and the Cu substrate was different from that of the typical SAC solders. In conclusion, alloying the SCNG solder with Ag, Bi, In or Sb is able to improve particular properties of the solder.展开更多
Amorphous Mg55Ni35Si10 powders are fabricated by using a mechanical alloying technique. The amorphous powders are found to exhibit a relatively high crystallization temperature of 380℃. The as-milled amorphous Mg55Ni...Amorphous Mg55Ni35Si10 powders are fabricated by using a mechanical alloying technique. The amorphous powders are found to exhibit a relatively high crystallization temperature of 380℃. The as-milled amorphous Mg55Ni35Si10 powders are consolidated successfully into bulk body by vacuum hot pressing technique. Limited nanocrystallization is noticed. The Vickers microhardness range of the Mg55Ni35Si10 bulk sample is 7834 to 8048 MPa. Its bending strength and compressive strength are 529 MPa and 1466 MPa, respectively.展开更多
文摘The diagram of Ag-Cu-Ge system was constructed from the investigation of 13 internal sec- tions by DTA heating as well as cooling curves in an atomsphere of dry N_2 . The phase dia- gram is subdivided into two pseudo-ternary systems shown as Ag-Cu-Cu_3Ge and Ag-Cu_3Ge-Ge. Both systems belong to simple eutectic type. The ternary eutectic points lie in.' E_1, Ag(22.0)-Cu(58.8)-Ge(19.2), 632℃ and E_2 , Ag(44.3)-Cu(29.5)-Ge(26.2), 533℃. The three side binary systems were redetermined.
基金Projects (50901025,50975060,51331005) supported by the National Natural Science Foundation of ChinaProject (2011CB610406) supported by the National Basic Research Program of China+2 种基金Projects (201104420,20090450840) supported by China Postdoctoral Science FoundationProject (JC201209) supported by Outstanding Young Scientist Foundation of Heilongjiang Province,ChinaProject (HIT.BRET1.20100008) supported by the Fundamental Research Funds for Central Universities,China
文摘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 wim 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.
文摘对添加少量合金元素Cu和Ge的Zr-4+xCu+xGe(x=0、0.05、0.1、0.2,质量分数,%)合金在360℃/18.6 MPa/0.01 M LiOH水溶液中进行静态高压釜腐蚀试验。利用TEM和SEM研究了合金和氧化膜的显微组织。结果表明:添加适量Cu和Ge可以延缓氧化膜中微裂纹的形成,显著提高Zr-4合金在360℃/18.6 MPa/0.01 M LiOH水溶液中的耐腐蚀性能;在Zr-4+xCu+xGe合金中主要析出密排六方结构的Zr(Fe,Cr)_2和Zr(Fe,Cr,Cu,Ge)_2型第二相,随着Cu和Ge添加量的进一步提高,还会有粗大的四方结构的Zr_2Cu和Zr_3Ge第二相析出,第二相的氧化易导致应力集中并促进微裂纹形成,不利于Zr-4合金耐腐蚀性能的改善。
基金King Mongkut’s Institute of Technology Ladkrabang and the National Research Council of Thailand for the financial sponsorship of this project
文摘The Sn-Cu-Ni-Ge solder is a strong challenger to the Sn-Ag-Cu(SAC) solders as a replacement for the Sn-Pb eutectic solder. This research investigated the effects of addition of Ag, Bi, In, and Sb on the physical properties of the Sn-0.6 Cu-0.05 Ni-Ge(SCNG) lead-free solder and the interfacial reaction with the Cu substrate. The melting behavior, microstructure, tensile strength, and wettability of the SCNG-x(x=Ag, Bi, In, Sb) solders were examined. The findings revealed that the introduction of Ag, Bi, In, and Sb minimally altered the solidus temperature, liquidus temperature, and tensile strength of the solder. However, the cooling behavior and solidified microstructure of the solder were affected by the concentration of the alloying elements. The wettability of the SCNG solder was improved with the doping of the alloying elements except Sb. The thickness of intermetallic layer was increased by the addition of the alloying elements and was related to the cooling behavior of the solder. The morphology of intermetallic layer between the SCNG-x solders and the Cu substrate was different from that of the typical SAC solders. In conclusion, alloying the SCNG solder with Ag, Bi, In or Sb is able to improve particular properties of the solder.
基金Supported by the Natural Science Foundation of Anhui Province under Grant No 050440601.
文摘Amorphous Mg55Ni35Si10 powders are fabricated by using a mechanical alloying technique. The amorphous powders are found to exhibit a relatively high crystallization temperature of 380℃. The as-milled amorphous Mg55Ni35Si10 powders are consolidated successfully into bulk body by vacuum hot pressing technique. Limited nanocrystallization is noticed. The Vickers microhardness range of the Mg55Ni35Si10 bulk sample is 7834 to 8048 MPa. Its bending strength and compressive strength are 529 MPa and 1466 MPa, respectively.