In order to realize the effective jointing of tungsten and Cu Cr Zr alloys manufactured for plasma facing components（PFCs）, explosive welding is employed for its some unique advantages. Different welding characteris...In order to realize the effective jointing of tungsten and Cu Cr Zr alloys manufactured for plasma facing components（PFCs）, explosive welding is employed for its some unique advantages. Different welding characteristics were investigated in this study. The interfacial waveform of the welded plates changed periodically from flat-wavelet to a large wave and finally to a stable wave, which began with the detonation point. The bonding strength of the specimens is higher than 32.9 MPa. Welding hardening and the formation of microcracks occurred at the interface zone. The results demonstrate that the joining reliabilities need to be improved in order to meet the need of applications involving the use of explosive welding to fabricate tungsten-based PFCs.展开更多
A recycled aggregate(RA)was prepared by crushing and sieving demolished discarded concrete pavements and was subsequently tested and analyzed to determine its various physical properties.On this basis,pervious concret...A recycled aggregate(RA)was prepared by crushing and sieving demolished discarded concrete pavements and was subsequently tested and analyzed to determine its various physical properties.On this basis,pervious concrete(PC)mix proportions were designed.Coarse RA particles with sizes of 5–10 and 10–20 mm were selected.Concrete specimens were prepared with a water–cement ratio of 0.3,an aggregate–cement ratio of 4.5,the substitute rates of RA with 0,25%,50%,75%and a single-/double-gap-graded RA mix(mass ratio of particles with sizes of 5–10 mm to particles with sizes of 10–20 mm:1:1,1:2,2:1,2:3 and 3:2).Various properties of the RA-containing PC(RPC)were determined by analyzing the compressive strength,splitting tensile strength,effective porosity,permeation coefficient and impact and abrasion resistance of the specimens.The results showed the following:The density of the RPC decreased with an increasing RA replacement ratio.The density of the RPC prepared with a double-gapgraded RA mix was lower than that prepared with a single-gap-graded RA(particle size:10–20 mm)mix.The permeation coefficient of the RPC increased with increasing porosity.The splitting tensile strength of the RPC was positively correlated with its compressive strength.The compressive strength of the RPC decreased with increasing porosity.The regression analysis showed that the impact and abrasion resistance of the RPC increased with increasing compressive strength.In addition,all of the RPC specimens met the strength and permeation requirements.This study can provide theoretical support for the application of RPC.展开更多
基金financial supports from the ITER-National Magnetic Confinement Fusion Program (Nos. 2014GB123000 and 2010GB109000)the National Natural Science Foundation of China (No. 51172016)
文摘In order to realize the effective jointing of tungsten and Cu Cr Zr alloys manufactured for plasma facing components（PFCs）, explosive welding is employed for its some unique advantages. Different welding characteristics were investigated in this study. The interfacial waveform of the welded plates changed periodically from flat-wavelet to a large wave and finally to a stable wave, which began with the detonation point. The bonding strength of the specimens is higher than 32.9 MPa. Welding hardening and the formation of microcracks occurred at the interface zone. The results demonstrate that the joining reliabilities need to be improved in order to meet the need of applications involving the use of explosive welding to fabricate tungsten-based PFCs.
基金This study was funded by the National key research and development program fund project(No.2018YFC0406803).
文摘A recycled aggregate(RA)was prepared by crushing and sieving demolished discarded concrete pavements and was subsequently tested and analyzed to determine its various physical properties.On this basis,pervious concrete(PC)mix proportions were designed.Coarse RA particles with sizes of 5–10 and 10–20 mm were selected.Concrete specimens were prepared with a water–cement ratio of 0.3,an aggregate–cement ratio of 4.5,the substitute rates of RA with 0,25%,50%,75%and a single-/double-gap-graded RA mix(mass ratio of particles with sizes of 5–10 mm to particles with sizes of 10–20 mm:1:1,1:2,2:1,2:3 and 3:2).Various properties of the RA-containing PC(RPC)were determined by analyzing the compressive strength,splitting tensile strength,effective porosity,permeation coefficient and impact and abrasion resistance of the specimens.The results showed the following:The density of the RPC decreased with an increasing RA replacement ratio.The density of the RPC prepared with a double-gapgraded RA mix was lower than that prepared with a single-gap-graded RA(particle size:10–20 mm)mix.The permeation coefficient of the RPC increased with increasing porosity.The splitting tensile strength of the RPC was positively correlated with its compressive strength.The compressive strength of the RPC decreased with increasing porosity.The regression analysis showed that the impact and abrasion resistance of the RPC increased with increasing compressive strength.In addition,all of the RPC specimens met the strength and permeation requirements.This study can provide theoretical support for the application of RPC.
