Ni-based superalloy K465 is brazed with BNi-2 filler metal by vacuum electron beam brazing （VEBB）. In process of VEBB, effects of processing primary parameters on shear strength of joints are investigated. Microstru...Ni-based superalloy K465 is brazed with BNi-2 filler metal by vacuum electron beam brazing （VEBB）. In process of VEBB, effects of processing primary parameters on shear strength of joints are investigated. Microstructure of the brazed joint with BNi-2 filler metal is studied by means of scanning electron microscopy （ SEM）, energy dispersive spectroscopy （EDS） and X-ray diffraction （XRD）. The results show that the structure of brazed seam consists of a large amount of Ni- based γ solid solution, Ni3Al （ γ＇） , Ni3B, WB, CrB, and a small quantity of WC, NbC, The maximum shear strength of the joint is 398 MPa when the beam current of welding is 2.6 mA, heating time is 480 s and focused current is 1 800 mA.展开更多
The permeability,alkali silica reaction,workability and strength of GHPC(green high performance concrete) were studied in this paper.The results show that GHPC has an excellent durability and the effects of mass rat...The permeability,alkali silica reaction,workability and strength of GHPC(green high performance concrete) were studied in this paper.The results show that GHPC has an excellent durability and the effects of mass ratio of flyash to high calcium slag,water binder ratio,content of water reducer,and crushed coarse aggregate type on the workability and strength of GHPC were considerably evident.A new path for the concretes continuous development was put forward.展开更多
In order to understand the strength developing law of the epoxy asphalt mixture,a curing reaction model of the epoxy asphalt binder was proposed based upon the thermokinetic analysis.Given some assumptions,the model w...In order to understand the strength developing law of the epoxy asphalt mixture,a curing reaction model of the epoxy asphalt binder was proposed based upon the thermokinetic analysis.Given some assumptions,the model was developed by applying the Kissinger law as well as Arrhenius equation,and the differential scanning calorimetry was performed for estimating the model parameters.To monitor the strength development of the epoxy asphalt mixture,a strength test program was employed and then results were compared to those produced from the proposed model.The comparative evaluation shows that a good consistency exists between the outputs from test program and the proposed model,indicating that the proposed model can be used effectively for simulating the curing reaction process for the epoxy asphalt binder and predicting the strength development for the epoxy asphalt mixture.展开更多
文摘Ni-based superalloy K465 is brazed with BNi-2 filler metal by vacuum electron beam brazing （VEBB）. In process of VEBB, effects of processing primary parameters on shear strength of joints are investigated. Microstructure of the brazed joint with BNi-2 filler metal is studied by means of scanning electron microscopy （ SEM）, energy dispersive spectroscopy （EDS） and X-ray diffraction （XRD）. The results show that the structure of brazed seam consists of a large amount of Ni- based γ solid solution, Ni3Al （ γ＇） , Ni3B, WB, CrB, and a small quantity of WC, NbC, The maximum shear strength of the joint is 398 MPa when the beam current of welding is 2.6 mA, heating time is 480 s and focused current is 1 800 mA.
文摘The permeability,alkali silica reaction,workability and strength of GHPC(green high performance concrete) were studied in this paper.The results show that GHPC has an excellent durability and the effects of mass ratio of flyash to high calcium slag,water binder ratio,content of water reducer,and crushed coarse aggregate type on the workability and strength of GHPC were considerably evident.A new path for the concretes continuous development was put forward.
基金Funded by the Project of National Science and Technology Ministry of China(No.2009BAG15B03)
文摘In order to understand the strength developing law of the epoxy asphalt mixture,a curing reaction model of the epoxy asphalt binder was proposed based upon the thermokinetic analysis.Given some assumptions,the model was developed by applying the Kissinger law as well as Arrhenius equation,and the differential scanning calorimetry was performed for estimating the model parameters.To monitor the strength development of the epoxy asphalt mixture,a strength test program was employed and then results were compared to those produced from the proposed model.The comparative evaluation shows that a good consistency exists between the outputs from test program and the proposed model,indicating that the proposed model can be used effectively for simulating the curing reaction process for the epoxy asphalt binder and predicting the strength development for the epoxy asphalt mixture.
