The development of Mg-Al-Zn-Mn-Ca series alloys provides a potential prospect to achieve high strength and formability at room temperature(RT).The formation of elliptical annular texture is treated as a crucial factor...The development of Mg-Al-Zn-Mn-Ca series alloys provides a potential prospect to achieve high strength and formability at room temperature(RT).The formation of elliptical annular texture is treated as a crucial factor for the enhanced RT formability.However,the origin of such an elliptical annular texture formation has been rarely reported.Herein,we unveiled the formation and evolution of elliptical annular texture in the hot-rolled Mg-1.6 Al-0.8 Zn-0.4 Mn-0.5 Ca(AZMX1100,wt.%)alloy after annealing at different temperatures for 1 h,and its static recrystallization(SRX)kinetics in given annealing temperature for different time.The results revealed that the formation of elliptical annular texture in the hot-rolled AZMX1100 alloy after annealing was derived from nucleation-oriented SRX mechanism,which took place in 200-300°C,induced by cracked chain-shaped Al2 Ca phases,contraction twins,intersections of double twins,intersections of double twins and grain boundaries and non-basal slips.On further annealing from300-450°C,the grains with 45°–70°transverse direction(TD)preferentially grew,which made elliptical annular texture extended along the TD.Based on the Johnson-Mehl-Avrami-Kolmogorov(JMAK)model,Avrami exponent n value was estimated to be 0.68–1.02,attributed to non-random SRX nucleation,giving rise to the lower activation energy QRof nucleation of^74.24 k J/mol.Since the co-segregation of Al,Zn and Ca atoms in grain boundaries created a strong interaction of solutes and grain boundaries,the hot-rolled AZMX1100 alloy exhibited the higher activation energy Qg(~115.48 k J/mol)of grain growth.展开更多
Mg−1Mn−0.5Al−0.5Ca−0.5Zn(wt.%)alloy was fabricated by conventional extrusion at 673 K with an extrusion ratio of 25:1,followed by aging at 473 K.The microstructure was characterized by scanning electron microscopy,ele...Mg−1Mn−0.5Al−0.5Ca−0.5Zn(wt.%)alloy was fabricated by conventional extrusion at 673 K with an extrusion ratio of 25:1,followed by aging at 473 K.The microstructure was characterized by scanning electron microscopy,electron back-scattered diffraction,and transmission electron microscopy.The mechanical properties were determined by the tensile test.The peak-aged sample shows fine recrystallized grains with an average grain size of 1.7μm.Area fraction of Al−Ca particles in the alloy increases significantly after peak aging.Meanwhile,botháañandác+añdislocations were observed to remain in the alloy after hot extrusion.Thus,the peak-aged sample exhibits simultaneously high strength and good ductility with the ultimate tensile stress,tensile yield stress,and tension fracture elongation of 320 MPa,314 MPa,and 19.0%,respectively.展开更多
目的通过电感耦合等离子体质谱(inductively coupled plasma mass spectrometry,ICP-MS)法建立加味左金丸中Cd、Pb、As、Hg、Co、V、Ni、Cu、Li、Sb、Ba、Mo、Sn、Cr、Na、Mg、Al、Ca、Ti、Mn、Fe、Zn、Ga、Se、Sr、Tl共计26种无机元素...目的通过电感耦合等离子体质谱(inductively coupled plasma mass spectrometry,ICP-MS)法建立加味左金丸中Cd、Pb、As、Hg、Co、V、Ni、Cu、Li、Sb、Ba、Mo、Sn、Cr、Na、Mg、Al、Ca、Ti、Mn、Fe、Zn、Ga、Se、Sr、Tl共计26种无机元素的测定方法。方法加味左金丸通过微波消解法处理后,根据相对分子质量的大小选择内标物,其中^(7)Li、^(23)Na、^(24)Mg、^(27)Al、^(40)Ca、^(48)Ti、^(51)V、^(52)Cr、^(55)Mn、^(56)Fe、^(58)Ni、^(59)Co、^(63)Cu、^(66)Zn、^(70)Ga、^(75)As、^(77)Se、^(86)Sr以^(72)Ge作为内标;^(95)Mo、^(114)Cd、^(118)Sn、^(121)Sb、^(137)Ba以^(115)In作为内标;^(202)Hg、^(205)Tl、^(208)Pb以^(209)Bi作为内标。对标准品溶液、空白溶液与供试品溶液进行分析,采用标准曲线法进行定量分析。通过ICP-MS法进行测定。结果26种无机元素线性的相关系数r≥0.9996,检出限为0.001~1.500μg/L,定量限为0.01~5.00μg/L,精密度与重复性试验的RSD均小于5%,平均回收率在82.64%~106.44%,RSD均小于5%。对3个厂家的12批样品进行了测定,26种元素的含量差异较大,其中Na、Mg、Ca、Fe 4种元素的含量比较高,均大于500μg/g,Cd、Pb、As、Hg、Co、Li、Sb、Mo、Sn、Cr、Se、Tl的含量比较低,均小于1μg/g。由结果可知,人体的常量元素,如Na、Mg、Ca的含量比较高,Cd、Pb、As、Hg等有害元素含量比较低。根据《中国药典》2020年版一部的要求,本品中Cd、Pb、As、Hg与Cu均符合规定。结论该方法快速、准确,可以用于加味左金丸中无机元素的测定。展开更多
目的建立微波消解-电感耦合等离子体质谱(ICP-MS)直接稀释测定脉络宁注射液中25种矿物质元素(Mg、Ca、Fe、Cu、Zn、Mn、Al、B、Ba、Co、Cr、K、Li、Mo、Na、Ni、P、Pb、Sr、Th、Ti、V、As、Cd和Hg)的方法。方法分别对微波消解条件...目的建立微波消解-电感耦合等离子体质谱(ICP-MS)直接稀释测定脉络宁注射液中25种矿物质元素(Mg、Ca、Fe、Cu、Zn、Mn、Al、B、Ba、Co、Cr、K、Li、Mo、Na、Ni、P、Pb、Sr、Th、Ti、V、As、Cd和Hg)的方法。方法分别对微波消解条件和测试条件进行考察;样品经微波消解后,采用电感耦合质谱仪测定25种矿物质元素,并对测定方法学进行考察。结果确定最佳消解条件为3步缓慢升温:400 W 80℃升温10 min,保留5 min;600 W 120℃升温10 min,保留5 min;900 W 200℃升温20 min,保留20 min;25种矿物质元素在各自的线性范围内线性关系良好,r≥0.999 6,精密度、稳定性和重复性试验的RSD均符合定量分析要求;加标回收率为94.7%~106.1%,RSD在0.34%~2.79%。脉络宁注射液中检测出Mg、Ca、Fe、Cu、Zn、Mn、Al、B、Ba、Co、Cr、K、Li、Mo、Na、Ni、P、Pb、Sr、Th、Ti、V,未检出As、Cd和Hg。结论该方法简便、迅速、准确,适用于脉络宁注射液中25种矿物质元素的同时测定。展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.51531002 and U1764253)the National Key Research and Development Program of China(Nos.2016YFB0301104 and 2016YFB0101700)+2 种基金the Chongqing Scientific&Technological Talents Program(No.KJXX2017002)the Chongqing Science and Technology Commission(No.cstc2018jcyj AX0472)the Science and Technology Research Program of Chongqing Municipal Education Commission(No.KJQN201801306)。
文摘The development of Mg-Al-Zn-Mn-Ca series alloys provides a potential prospect to achieve high strength and formability at room temperature(RT).The formation of elliptical annular texture is treated as a crucial factor for the enhanced RT formability.However,the origin of such an elliptical annular texture formation has been rarely reported.Herein,we unveiled the formation and evolution of elliptical annular texture in the hot-rolled Mg-1.6 Al-0.8 Zn-0.4 Mn-0.5 Ca(AZMX1100,wt.%)alloy after annealing at different temperatures for 1 h,and its static recrystallization(SRX)kinetics in given annealing temperature for different time.The results revealed that the formation of elliptical annular texture in the hot-rolled AZMX1100 alloy after annealing was derived from nucleation-oriented SRX mechanism,which took place in 200-300°C,induced by cracked chain-shaped Al2 Ca phases,contraction twins,intersections of double twins,intersections of double twins and grain boundaries and non-basal slips.On further annealing from300-450°C,the grains with 45°–70°transverse direction(TD)preferentially grew,which made elliptical annular texture extended along the TD.Based on the Johnson-Mehl-Avrami-Kolmogorov(JMAK)model,Avrami exponent n value was estimated to be 0.68–1.02,attributed to non-random SRX nucleation,giving rise to the lower activation energy QRof nucleation of^74.24 k J/mol.Since the co-segregation of Al,Zn and Ca atoms in grain boundaries created a strong interaction of solutes and grain boundaries,the hot-rolled AZMX1100 alloy exhibited the higher activation energy Qg(~115.48 k J/mol)of grain growth.
基金the financial supports from the Fundamental Research Funds for the Central Universities,China(Nos.2019CDCGCL316,2020CDJDPT001)Chongqing Research Program of Basic Research and Frontier Technology,China(No.cstc2019jcjy-msxmX0539)。
文摘Mg−1Mn−0.5Al−0.5Ca−0.5Zn(wt.%)alloy was fabricated by conventional extrusion at 673 K with an extrusion ratio of 25:1,followed by aging at 473 K.The microstructure was characterized by scanning electron microscopy,electron back-scattered diffraction,and transmission electron microscopy.The mechanical properties were determined by the tensile test.The peak-aged sample shows fine recrystallized grains with an average grain size of 1.7μm.Area fraction of Al−Ca particles in the alloy increases significantly after peak aging.Meanwhile,botháañandác+añdislocations were observed to remain in the alloy after hot extrusion.Thus,the peak-aged sample exhibits simultaneously high strength and good ductility with the ultimate tensile stress,tensile yield stress,and tension fracture elongation of 320 MPa,314 MPa,and 19.0%,respectively.
文摘目的建立微波消解-电感耦合等离子体质谱(ICP-MS)直接稀释测定脉络宁注射液中25种矿物质元素(Mg、Ca、Fe、Cu、Zn、Mn、Al、B、Ba、Co、Cr、K、Li、Mo、Na、Ni、P、Pb、Sr、Th、Ti、V、As、Cd和Hg)的方法。方法分别对微波消解条件和测试条件进行考察;样品经微波消解后,采用电感耦合质谱仪测定25种矿物质元素,并对测定方法学进行考察。结果确定最佳消解条件为3步缓慢升温:400 W 80℃升温10 min,保留5 min;600 W 120℃升温10 min,保留5 min;900 W 200℃升温20 min,保留20 min;25种矿物质元素在各自的线性范围内线性关系良好,r≥0.999 6,精密度、稳定性和重复性试验的RSD均符合定量分析要求;加标回收率为94.7%~106.1%,RSD在0.34%~2.79%。脉络宁注射液中检测出Mg、Ca、Fe、Cu、Zn、Mn、Al、B、Ba、Co、Cr、K、Li、Mo、Na、Ni、P、Pb、Sr、Th、Ti、V,未检出As、Cd和Hg。结论该方法简便、迅速、准确,适用于脉络宁注射液中25种矿物质元素的同时测定。