Anodic bonding of glass to Kovar alloy coated with Al film (Glass Al film/Kovar) was performed in the temperature range of 513 ～ 713?K under the static electric voltage of 500?V in order to investigate the interfacia...Anodic bonding of glass to Kovar alloy coated with Al film (Glass Al film/Kovar) was performed in the temperature range of 513 ～ 713?K under the static electric voltage of 500?V in order to investigate the interfacial phenomena of Al glass joint. The results reveal that Na and K ions within the glass are displaced by the applied field from the anode side surface of the glass to form depletion layers of them. The K ion depletion layer is narrow and followed by a K pile up layer, and both the two layers are formed within the Na depletion layer. The width of the Na and K depletion layers is increased with increasing bonding temperature and time. The activation energies for the growth of both depletion layers were close to that for Na diffusion in the glass. TEM observations reveal that Al film coated at the surface of Kovar alloy is oxidized to amorphous Al 2O 3 containing a few of Fe, Ni and Co by oxygen ions from the glass drifted by high electric field during bonding. The amount of Fe ions diffusing into the glass adjacent to the anode is significantly low due to the presence of Al film between Kovar alloy and the glass. As a result, the amorphous reaction layer of Fe Si O in the glass near the interface is avoided which is formed in Kovar glass joints.展开更多
The interfacial reactions of chalcopyrite in ammonia–ammonium chloride solution were investigated.The chalcopyrite surface was examined by scanning electron microscopy and X-ray photoelectron spectroscopy(XPS)techniq...The interfacial reactions of chalcopyrite in ammonia–ammonium chloride solution were investigated.The chalcopyrite surface was examined by scanning electron microscopy and X-ray photoelectron spectroscopy(XPS)techniques.It was found that interfacial passivation layers of chalcopyrite were formed from an iron oxide layer on top of a copper sulfide layer overlaying the bulk chalcopyrite,whereas CuFe1-xS2 or copper sulfides were formed via the preferential dissolution of Fe.The copper sulfide layer formed a new passivation layer,whereas the iron oxide layer peeled off spontaneously and partially from the chalcopyrite surface.The state of the copper sulfide layer was discussed after being deduced from the appearance of S2-,S22-,Sn2-,S0 and SO42-.A mechanism for the oxidation and passivation of chalcopyrite under different pH values and redox potentials was proposed.Accordingly,a model of the interfacial reaction on the chalcopyrite surface was constructed using a three-step reaction pathway,which demonstrated the formation and transformation of passivation layers under the present experimental conditions.展开更多
为了提高Si3N4陶瓷连接接头高温性能及减小接头因热膨胀系数不匹配而产生的应力,采用Ag Cu Ti钎料和NiTi复合中间层进行半固态连接。接头组织观察表明,钎缝主要由NiTi(Cu)金属间化合物和Ag Cu基体组成。研究表明,Ni与Ti的加入量对于钎...为了提高Si3N4陶瓷连接接头高温性能及减小接头因热膨胀系数不匹配而产生的应力,采用Ag Cu Ti钎料和NiTi复合中间层进行半固态连接。接头组织观察表明,钎缝主要由NiTi(Cu)金属间化合物和Ag Cu基体组成。研究表明,Ni与Ti的加入量对于钎缝中金属间化合物的形态及钎缝与母材界面反应层的形成具有十分重要的影响。展开更多
In the present investigation,the growth kinetics of interfacial reaction layer products between cubic boron nitride(CBN) and Cu-Sn-Ti filler metal has been thoroughly investigated.Detailed morphological and compositio...In the present investigation,the growth kinetics of interfacial reaction layer products between cubic boron nitride(CBN) and Cu-Sn-Ti filler metal has been thoroughly investigated.Detailed morphological and compositional features of respective compounds have been demonstrated for a wide brazing temperature ranging from 1153 K to 1223 K.It is found that within 30 minutes brazing holding time,the reaction layer growth is largely determined by the population of Ti N via effective Ti diffusion with an activation energy of 223.51 k J/mol,leading to parabolic growth patterns.It is further revealed that TiN grows both in axial and length dimensions,which eventually extends to the forefront and covers the reaction layer.展开更多
文摘Anodic bonding of glass to Kovar alloy coated with Al film (Glass Al film/Kovar) was performed in the temperature range of 513 ～ 713?K under the static electric voltage of 500?V in order to investigate the interfacial phenomena of Al glass joint. The results reveal that Na and K ions within the glass are displaced by the applied field from the anode side surface of the glass to form depletion layers of them. The K ion depletion layer is narrow and followed by a K pile up layer, and both the two layers are formed within the Na depletion layer. The width of the Na and K depletion layers is increased with increasing bonding temperature and time. The activation energies for the growth of both depletion layers were close to that for Na diffusion in the glass. TEM observations reveal that Al film coated at the surface of Kovar alloy is oxidized to amorphous Al 2O 3 containing a few of Fe, Ni and Co by oxygen ions from the glass drifted by high electric field during bonding. The amount of Fe ions diffusing into the glass adjacent to the anode is significantly low due to the presence of Al film between Kovar alloy and the glass. As a result, the amorphous reaction layer of Fe Si O in the glass near the interface is avoided which is formed in Kovar glass joints.
基金Project(2014CB643405)supported by the National Basic Research Program of China
文摘The interfacial reactions of chalcopyrite in ammonia–ammonium chloride solution were investigated.The chalcopyrite surface was examined by scanning electron microscopy and X-ray photoelectron spectroscopy(XPS)techniques.It was found that interfacial passivation layers of chalcopyrite were formed from an iron oxide layer on top of a copper sulfide layer overlaying the bulk chalcopyrite,whereas CuFe1-xS2 or copper sulfides were formed via the preferential dissolution of Fe.The copper sulfide layer formed a new passivation layer,whereas the iron oxide layer peeled off spontaneously and partially from the chalcopyrite surface.The state of the copper sulfide layer was discussed after being deduced from the appearance of S2-,S22-,Sn2-,S0 and SO42-.A mechanism for the oxidation and passivation of chalcopyrite under different pH values and redox potentials was proposed.Accordingly,a model of the interfacial reaction on the chalcopyrite surface was constructed using a three-step reaction pathway,which demonstrated the formation and transformation of passivation layers under the present experimental conditions.
文摘为了提高Si3N4陶瓷连接接头高温性能及减小接头因热膨胀系数不匹配而产生的应力,采用Ag Cu Ti钎料和NiTi复合中间层进行半固态连接。接头组织观察表明,钎缝主要由NiTi(Cu)金属间化合物和Ag Cu基体组成。研究表明,Ni与Ti的加入量对于钎缝中金属间化合物的形态及钎缝与母材界面反应层的形成具有十分重要的影响。
基金the support from the National Natural Science Foundation of China (U20A20277, 52011530180, 52050410341, 51861130361, and 51861145312)Newton Advanced Fellowship by Royal Society (RP12G0414)+5 种基金Royal Academy of Engineering (TSPC-1070)Research Fund for Central Universities (N2025025)Xing Liao Talents Program (XLYC1807024 and XLYC1802024)Project funded by China Postdoctoral Science Foundation (2020TQ0060 and 2020M680965)NEU Innovation Team Project, Regional Innovation Joint Fund of Liaoning Province (2020-YKLH-39)Global Talents Recruitment Program endowed by the Chinese Government for their financial support。
文摘In the present investigation,the growth kinetics of interfacial reaction layer products between cubic boron nitride(CBN) and Cu-Sn-Ti filler metal has been thoroughly investigated.Detailed morphological and compositional features of respective compounds have been demonstrated for a wide brazing temperature ranging from 1153 K to 1223 K.It is found that within 30 minutes brazing holding time,the reaction layer growth is largely determined by the population of Ti N via effective Ti diffusion with an activation energy of 223.51 k J/mol,leading to parabolic growth patterns.It is further revealed that TiN grows both in axial and length dimensions,which eventually extends to the forefront and covers the reaction layer.
