(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]是新型含能钙钛矿化合物的典型代表,需明确其热分解行为、热分解机制及感度特性,以推动其在配方中的应用。以差示扫描量热-热重分析方法实现了分解放热量、分解温度等参数的获取;以动力学模拟计算...(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]是新型含能钙钛矿化合物的典型代表,需明确其热分解行为、热分解机制及感度特性,以推动其在配方中的应用。以差示扫描量热-热重分析方法实现了分解放热量、分解温度等参数的获取;以动力学模拟计算解析了相关分解机理;以同步热分析-红外-质谱联用技术结合原位红外技术探索了(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]的分解产物及分解历程;以国军标法获得了热感度、摩擦感度与撞击感度参数。结果表明:在10℃·min^(-1)的升温速率下,(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]分解放热量为4227 J·g^(-1),分解温度则达到345℃,高于黑索今(RDX)、奥克托今(HMX)、六硝基六氮杂异伍兹烷(CL-20)等多数现役含能材料,显示了优异的热稳定性;分解产物研究表明其立方笼状骨架有效稳定了内部结合的有机物分子,使其热稳定性较高。此外,(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]在100℃下加热48 h的放气量约0.04 m L·g^(-1),撞击感度与机械感度分别为32%和80%,优于RDX和HMX。展开更多
The new ternary CM_2A_8(CaMg_2Al_(16)O_(27))and C_2M_2A_(14)(Ca_2Mg_2Al_(28)O_(46))pure and dense ceramics were first prepared by a hot-press sintering technique,and their physical and mechanical properties were inves...The new ternary CM_2A_8(CaMg_2Al_(16)O_(27))and C_2M_2A_(14)(Ca_2Mg_2Al_(28)O_(46))pure and dense ceramics were first prepared by a hot-press sintering technique,and their physical and mechanical properties were investigated.The purity of obtained CM_2A_8 and C_2M_2A_(14) ceramics reaches 98.1 wt%and 97.5 wt%,respectively.Their microstructure is dense with few observable pores,and their grain size is about a few dozen microns.For their physical properties,the average apparent porosity of CM_2A_8 and C_2M_2A_(14) ceramics is 0.18% and 0.13%,and their average bulk density is 3.66 g/cm^3 and 3.71 g/cm^3,respectively.The relative density of CM_2A_8 ceramic is 98.12%and that of C_2M_2A_(14)ceramic is 98.67%.The thermal expansivity(50–1400℃)of CM_2A_8 and C_2M_2A_(14) ceramics is 9.24×10^(–6)K^(–1) and 8.92×10^(–6)K^(–1),respectively.The thermal conductivity of CM_2A_8 and C_2M_2A_(14) ceramic is 21.32 W/(m·K)and 23.25 W/(m·K)at 25℃and 18.76 W/(m·K)and 19.42 W/(m·K)as temperature rises to 350℃,respectively.In addition,the mechanical properties are also achieved.For CM_2A_8 ceramic,the flexural strength is 248 MPa,the fracture toughness is 2.17 MPa·m^(1/2),and the Vickers hardness is 12.26 GPa.For C_2M_2A_(14) ceramic,the flexural strength is 262 MPa,the fracture toughness is 2.23 MPa·m^(1/2),and the Vickers hardness is 12.95 GPa.展开更多
以COST-FB2转子钢为研究对象,利用冲击试验、高温拉伸试验、硬度测试、扫描电镜、透射电镜及X射线衍射仪等测试方法研究了630℃长期时效中COST-FB2转子钢组织和性能的变化。结果表明:随着时效时间延长,冲击功、硬度和高温强度都呈下降趋...以COST-FB2转子钢为研究对象,利用冲击试验、高温拉伸试验、硬度测试、扫描电镜、透射电镜及X射线衍射仪等测试方法研究了630℃长期时效中COST-FB2转子钢组织和性能的变化。结果表明:随着时效时间延长,冲击功、硬度和高温强度都呈下降趋势,冲击韧性在2000h后下降较为明显,后逐渐趋于稳定。硬度(HBW)总体处在较高水平(2479.4MPa),高温塑性未见明显变化。M_(23)C_(6)碳化物尺寸及含量有所增长,但未见明显粗化;Laves相尺寸增长更明显并在晶界处聚集,但未形成链状。Laves相的析出长大与聚集是导致冲击韧性下降的主要原因。研究结果认为630℃时效至5000 h COST-FB2钢能够保持较高的高温稳定性。展开更多
文摘(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]是新型含能钙钛矿化合物的典型代表,需明确其热分解行为、热分解机制及感度特性,以推动其在配方中的应用。以差示扫描量热-热重分析方法实现了分解放热量、分解温度等参数的获取;以动力学模拟计算解析了相关分解机理;以同步热分析-红外-质谱联用技术结合原位红外技术探索了(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]的分解产物及分解历程;以国军标法获得了热感度、摩擦感度与撞击感度参数。结果表明:在10℃·min^(-1)的升温速率下,(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]分解放热量为4227 J·g^(-1),分解温度则达到345℃,高于黑索今(RDX)、奥克托今(HMX)、六硝基六氮杂异伍兹烷(CL-20)等多数现役含能材料,显示了优异的热稳定性;分解产物研究表明其立方笼状骨架有效稳定了内部结合的有机物分子,使其热稳定性较高。此外,(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]在100℃下加热48 h的放气量约0.04 m L·g^(-1),撞击感度与机械感度分别为32%和80%,优于RDX和HMX。
基金supported by the National Natural Science Foundation of China (No. 51572019)the National Science Fund for Excellent Young Scholars of China (No. 51522402)
文摘The new ternary CM_2A_8(CaMg_2Al_(16)O_(27))and C_2M_2A_(14)(Ca_2Mg_2Al_(28)O_(46))pure and dense ceramics were first prepared by a hot-press sintering technique,and their physical and mechanical properties were investigated.The purity of obtained CM_2A_8 and C_2M_2A_(14) ceramics reaches 98.1 wt%and 97.5 wt%,respectively.Their microstructure is dense with few observable pores,and their grain size is about a few dozen microns.For their physical properties,the average apparent porosity of CM_2A_8 and C_2M_2A_(14) ceramics is 0.18% and 0.13%,and their average bulk density is 3.66 g/cm^3 and 3.71 g/cm^3,respectively.The relative density of CM_2A_8 ceramic is 98.12%and that of C_2M_2A_(14)ceramic is 98.67%.The thermal expansivity(50–1400℃)of CM_2A_8 and C_2M_2A_(14) ceramics is 9.24×10^(–6)K^(–1) and 8.92×10^(–6)K^(–1),respectively.The thermal conductivity of CM_2A_8 and C_2M_2A_(14) ceramic is 21.32 W/(m·K)and 23.25 W/(m·K)at 25℃and 18.76 W/(m·K)and 19.42 W/(m·K)as temperature rises to 350℃,respectively.In addition,the mechanical properties are also achieved.For CM_2A_8 ceramic,the flexural strength is 248 MPa,the fracture toughness is 2.17 MPa·m^(1/2),and the Vickers hardness is 12.26 GPa.For C_2M_2A_(14) ceramic,the flexural strength is 262 MPa,the fracture toughness is 2.23 MPa·m^(1/2),and the Vickers hardness is 12.95 GPa.
基金National Key R&D Program of China(2017YFB0305202)Inner Mongolia Natural Science Foundation(2016MS0510,2020MS05046)+1 种基金Key Technology Research Program of Inner Mongolia Autonomous Region(2021GG0047)Basic Scientific Research Business Cost Project of Colleges and Universities Directly Under the Inner Mongolia Autonomous Region in 2023。
文摘以COST-FB2转子钢为研究对象,利用冲击试验、高温拉伸试验、硬度测试、扫描电镜、透射电镜及X射线衍射仪等测试方法研究了630℃长期时效中COST-FB2转子钢组织和性能的变化。结果表明:随着时效时间延长,冲击功、硬度和高温强度都呈下降趋势,冲击韧性在2000h后下降较为明显,后逐渐趋于稳定。硬度(HBW)总体处在较高水平(2479.4MPa),高温塑性未见明显变化。M_(23)C_(6)碳化物尺寸及含量有所增长,但未见明显粗化;Laves相尺寸增长更明显并在晶界处聚集,但未形成链状。Laves相的析出长大与聚集是导致冲击韧性下降的主要原因。研究结果认为630℃时效至5000 h COST-FB2钢能够保持较高的高温稳定性。