目的:研究硅烷偶联剂(CP)对瓷面及金属托槽黏接强度的影响。方法:将100个表面光滑的烤瓷试件按照不同的瓷面处理(喷砂、打磨、氢氟酸酸蚀、磷酸酸蚀、未处理)分为5组,再根据是否使用CP再将各组分为两组,每个小组10个试件,采用3M Unite T...目的:研究硅烷偶联剂(CP)对瓷面及金属托槽黏接强度的影响。方法:将100个表面光滑的烤瓷试件按照不同的瓷面处理(喷砂、打磨、氢氟酸酸蚀、磷酸酸蚀、未处理)分为5组,再根据是否使用CP再将各组分为两组,每个小组10个试件,采用3M Unite TM黏接剂粘接托槽,进行冷热水温度循环试验,采用材料试验机测量抗剪切强度,并记录瓷破裂指数。结果:甲、乙、丙三组剪切强度高于丁组合戊组,差异有统计学意义(P<0.05);甲2、乙2和丙2瓷面抗剪切强度高于甲1、乙1和丙1,差异有统计学意义(P<0.05);瓷破裂指数最高、最低的组别分别为丙2组及丁1组;甲1和甲2组、乙1和乙2组以及丙1和丙2组比较,瓷破裂指数的差异有统计学意义(P<0.05)。结论:对采用车针打磨、喷砂处理后的瓷面使用CP可有效的提高托槽与瓷面的粘结强度。展开更多
Electronic devices pervade everyday life,which has triggered severe electromagnetic(EM)wave pollution.To face this challenge,developing EM wave absorbers with ultra-broadband absorption capacity is critically required...Electronic devices pervade everyday life,which has triggered severe electromagnetic(EM)wave pollution.To face this challenge,developing EM wave absorbers with ultra-broadband absorption capacity is critically required.Currently,nano-composite construction has been widely utilized to realize impedance match and broadband absorption.However,complex experimental procedures,limited thermal stability,and interior oxidation resistance are still unneglectable issues.Therefore,it is appealing to realize ultra-broadband EM wave absorption in single-phase materials with good stability.Aiming at this target,two high-entropy transition metal carbides(HE TMCs)including(Zr,Hf,Nb,Ta)C(HE TMC-2)and(Cr,Zr,Hf,Nb,Ta)C(HE TMC-3)are designed and synthesized,of which the microwave absorption performance is investigated in comparison with previously reported(Ti,Zr,Hf,Nb,Ta)C(HE TMC-1).Due to the synergistic effects of dielectric and magnetic losses,HE TMC-2 and HE TMC-3 exhibit better impedance match and wider effective absorption bandwidth(EAB).In specific,the exclusion of Ti element in HE TMC-2 endows it optimal minimum reflection loss(RL_(min))and EAB of−41.7 dB(2.11 mm,10.52 GHz)and 3.5 GHz(at 3.0 mm),respectively.Remarkably,the incorporation of Cr element in HE TMC-3 significantly improves the impedance match,thus realizing EAB of 10.5,9.2,and 13.9 GHz at 2,3,and 4 mm,respectively.The significance of this study lays on realizing ultra-broadband capacity in HE TMC-3(Cr,Zr,Hf,Nb,Ta),demonstrating the effectiveness of high-entropy component design in tailoring the impedance match.展开更多
文摘目的:研究硅烷偶联剂(CP)对瓷面及金属托槽黏接强度的影响。方法:将100个表面光滑的烤瓷试件按照不同的瓷面处理(喷砂、打磨、氢氟酸酸蚀、磷酸酸蚀、未处理)分为5组,再根据是否使用CP再将各组分为两组,每个小组10个试件,采用3M Unite TM黏接剂粘接托槽,进行冷热水温度循环试验,采用材料试验机测量抗剪切强度,并记录瓷破裂指数。结果:甲、乙、丙三组剪切强度高于丁组合戊组,差异有统计学意义(P<0.05);甲2、乙2和丙2瓷面抗剪切强度高于甲1、乙1和丙1,差异有统计学意义(P<0.05);瓷破裂指数最高、最低的组别分别为丙2组及丁1组;甲1和甲2组、乙1和乙2组以及丙1和丙2组比较,瓷破裂指数的差异有统计学意义(P<0.05)。结论:对采用车针打磨、喷砂处理后的瓷面使用CP可有效的提高托槽与瓷面的粘结强度。
基金We gratefully acknowledge the financial support from the National Natural Science Foundation of China(Nos.51972089,51672064,and U1435206).
文摘Electronic devices pervade everyday life,which has triggered severe electromagnetic(EM)wave pollution.To face this challenge,developing EM wave absorbers with ultra-broadband absorption capacity is critically required.Currently,nano-composite construction has been widely utilized to realize impedance match and broadband absorption.However,complex experimental procedures,limited thermal stability,and interior oxidation resistance are still unneglectable issues.Therefore,it is appealing to realize ultra-broadband EM wave absorption in single-phase materials with good stability.Aiming at this target,two high-entropy transition metal carbides(HE TMCs)including(Zr,Hf,Nb,Ta)C(HE TMC-2)and(Cr,Zr,Hf,Nb,Ta)C(HE TMC-3)are designed and synthesized,of which the microwave absorption performance is investigated in comparison with previously reported(Ti,Zr,Hf,Nb,Ta)C(HE TMC-1).Due to the synergistic effects of dielectric and magnetic losses,HE TMC-2 and HE TMC-3 exhibit better impedance match and wider effective absorption bandwidth(EAB).In specific,the exclusion of Ti element in HE TMC-2 endows it optimal minimum reflection loss(RL_(min))and EAB of−41.7 dB(2.11 mm,10.52 GHz)and 3.5 GHz(at 3.0 mm),respectively.Remarkably,the incorporation of Cr element in HE TMC-3 significantly improves the impedance match,thus realizing EAB of 10.5,9.2,and 13.9 GHz at 2,3,and 4 mm,respectively.The significance of this study lays on realizing ultra-broadband capacity in HE TMC-3(Cr,Zr,Hf,Nb,Ta),demonstrating the effectiveness of high-entropy component design in tailoring the impedance match.
