Undercooling solidification under a magnetic field(UMF)is an effective way to tailor the microstructure and properties of Co-based alloys.In this study,by attributing to the UMF treatment,the strength−ductility trade-...Undercooling solidification under a magnetic field(UMF)is an effective way to tailor the microstructure and properties of Co-based alloys.In this study,by attributing to the UMF treatment,the strength−ductility trade-off dilemma in GH605 superalloy is successfully overcome.The UMF treatment can effectively refine the grains and increase the solid solubility,leading to the high yield strength.The main deformation mechanism in the as-forged alloy is dislocation slipping.By contrast,multiple deformation mechanisms,including stacking faults,twining,dislocation slipping,and their strong interactions are activated in the UMF-treated sample during compression deformation,which enhances the strength and ductility simultaneously.In addition,the precipitation of hard Laves phases along the grain boundaries can be obtained after UMF treatment,hindering crack propagation during compression deformation.展开更多
The solution of H 2O 2 is proposed to post-treat thick porous silicon (PS) films.The prepared PS film as the cathode is applied about 10mA/cm 2 current in mixture of ethanol,HF,and H 2O 2 solutions,which is expec...The solution of H 2O 2 is proposed to post-treat thick porous silicon (PS) films.The prepared PS film as the cathode is applied about 10mA/cm 2 current in mixture of ethanol,HF,and H 2O 2 solutions,which is expected to improve the stability and the smoothness of the surface and the mechanical property of the thick porous silicon films.The microstructure of the PS thick films with thicknesse of 20μm and 70μm has been studied.The SEM images show significant improved smoothness on surface of PS films,and XRD spectra suggest the formation of oxide layer after post-treating in H 2O 2.展开更多
[Objective] The paper was to evaluate effects of peracetic acid （PAA） combined with calcium treatments on storage quality of Ioquat fruits, so as to pro- vide practical techniques to solve the problems of postharves...[Objective] The paper was to evaluate effects of peracetic acid （PAA） combined with calcium treatments on storage quality of Ioquat fruits, so as to pro- vide practical techniques to solve the problems of postharvest rot and quality deteri- oration for Ioquat fruits. [Method] With Ioquat fruits of Qingzhong variety as materi- als, 0.2%, 0.4% and 0.8% PAA combined with 0.8% CaCI2 was used to soak Ioquat fruits for 4 min, 0.8% CaCl2 and water treatments were set as two controls; the fruits were dried and packaged by 0.02 mm PE bags, then stored under non-chilling low temperature of （7±1） ℃. The indicators related to storage quality of Ioquat fruits were randomly tested once every 3 d, and their variation situations were analyzed. [Result] Compared with two control treatments and 0.2% PAA, 0.8% PAA combined with calcium treatments, the treatment of 0.4% PAA combined with 0.8% CaCl2 could significantly inhibit rot index, weight loss rate, firmness and cell membrane permeability of Ioquat fruits during storage period, which could also effectively delay the reduction of titratable acid, vitamin C, soluble solid content and juice yield, and maintain respiration intensity of fruits at a low level; the appearance and flavor qual- ity of fruits were good after stored for 25 d. [Conclusion] 0.4% PAA combined with 0.8% CaCl2 treatment is an efficient, safe and economical practice technology in an- ti-corrosion and quality preservation for postharvest Ioquat fruits .展开更多
The effect of intermetallic compounds on the heat resistance of transition joint was investigated. The experiment of post-weld heat treatment for the hot roll bonded titanium alloy-stainless steel joint using nickels ...The effect of intermetallic compounds on the heat resistance of transition joint was investigated. The experiment of post-weld heat treatment for the hot roll bonded titanium alloy-stainless steel joint using nickels interlayer was carried out, and the interface microstructure evolution due to heat treatment was presented. There was not found significant interdiffusion at stainless steel/nickel interface, when the specimens were heat treated in the temperature range of 600-800 °C for 10 and 30 min, while micro-cracks occurred at the stainless steel/nickel interface heat treated at 700 °C for 30 min. The thickness of intermetallic layers at nickel/titanium alloy interface increased at 600 °C, and micro-cracks occurred at 700 and 800 °C. The micro-cracks occurred between intermetallic layers or between intermetallic layer and nickel interlayer as well. The tensile strength of the transition joint decreased with the increase of heat treatment temperature or holding time.展开更多
基金the fund of National Key Laboratory for Precision Hot Processing of Metals,China(No.6142909200104)State Key Laboratory of Solidification Processing(NPU),China(No.2022-TS-08)National Training Program of Innovation and Entrepreneurship for Undergraduates.We thank Dr.ZHENG from ZKKF(Beijing)Science&Technology Company for supporting the characterization of the materials.
文摘Undercooling solidification under a magnetic field(UMF)is an effective way to tailor the microstructure and properties of Co-based alloys.In this study,by attributing to the UMF treatment,the strength−ductility trade-off dilemma in GH605 superalloy is successfully overcome.The UMF treatment can effectively refine the grains and increase the solid solubility,leading to the high yield strength.The main deformation mechanism in the as-forged alloy is dislocation slipping.By contrast,multiple deformation mechanisms,including stacking faults,twining,dislocation slipping,and their strong interactions are activated in the UMF-treated sample during compression deformation,which enhances the strength and ductility simultaneously.In addition,the precipitation of hard Laves phases along the grain boundaries can be obtained after UMF treatment,hindering crack propagation during compression deformation.
文摘The solution of H 2O 2 is proposed to post-treat thick porous silicon (PS) films.The prepared PS film as the cathode is applied about 10mA/cm 2 current in mixture of ethanol,HF,and H 2O 2 solutions,which is expected to improve the stability and the smoothness of the surface and the mechanical property of the thick porous silicon films.The microstructure of the PS thick films with thicknesse of 20μm and 70μm has been studied.The SEM images show significant improved smoothness on surface of PS films,and XRD spectra suggest the formation of oxide layer after post-treating in H 2O 2.
基金Supported by Special Fund for Agro-scientific Research in the Public Interest "Tec-hnology Research and Experimental Demonstration of Loquat Industry"(201003073)~~
文摘[Objective] The paper was to evaluate effects of peracetic acid （PAA） combined with calcium treatments on storage quality of Ioquat fruits, so as to pro- vide practical techniques to solve the problems of postharvest rot and quality deteri- oration for Ioquat fruits. [Method] With Ioquat fruits of Qingzhong variety as materi- als, 0.2%, 0.4% and 0.8% PAA combined with 0.8% CaCI2 was used to soak Ioquat fruits for 4 min, 0.8% CaCl2 and water treatments were set as two controls; the fruits were dried and packaged by 0.02 mm PE bags, then stored under non-chilling low temperature of （7±1） ℃. The indicators related to storage quality of Ioquat fruits were randomly tested once every 3 d, and their variation situations were analyzed. [Result] Compared with two control treatments and 0.2% PAA, 0.8% PAA combined with calcium treatments, the treatment of 0.4% PAA combined with 0.8% CaCl2 could significantly inhibit rot index, weight loss rate, firmness and cell membrane permeability of Ioquat fruits during storage period, which could also effectively delay the reduction of titratable acid, vitamin C, soluble solid content and juice yield, and maintain respiration intensity of fruits at a low level; the appearance and flavor qual- ity of fruits were good after stored for 25 d. [Conclusion] 0.4% PAA combined with 0.8% CaCl2 treatment is an efficient, safe and economical practice technology in an- ti-corrosion and quality preservation for postharvest Ioquat fruits .
基金Project(AWPT-M07)supported by the State Key Laboratory of Advanced Welding and Joining,Harbin Institute of Technology
文摘The effect of intermetallic compounds on the heat resistance of transition joint was investigated. The experiment of post-weld heat treatment for the hot roll bonded titanium alloy-stainless steel joint using nickels interlayer was carried out, and the interface microstructure evolution due to heat treatment was presented. There was not found significant interdiffusion at stainless steel/nickel interface, when the specimens were heat treated in the temperature range of 600-800 °C for 10 and 30 min, while micro-cracks occurred at the stainless steel/nickel interface heat treated at 700 °C for 30 min. The thickness of intermetallic layers at nickel/titanium alloy interface increased at 600 °C, and micro-cracks occurred at 700 and 800 °C. The micro-cracks occurred between intermetallic layers or between intermetallic layer and nickel interlayer as well. The tensile strength of the transition joint decreased with the increase of heat treatment temperature or holding time.
