Microstructure and mechanical properties of aged Mg-10Gd-2Y-0.4Zr-0.4Ag alloy sheets prepared by different rolling routes were investigated.The results showed that the cross rolling aged(CRA)sheet possesses larger gra...Microstructure and mechanical properties of aged Mg-10Gd-2Y-0.4Zr-0.4Ag alloy sheets prepared by different rolling routes were investigated.The results showed that the cross rolling aged(CRA)sheet possesses larger grain size than unidirectional rolling aged(URA)sheet due to the occurrence of dynamic recovery during rolling which reduces the dislocation density and delays dynamic recrystallization(DRX).The URA sheet has basal texture and RD favored texture while CRA sheet has multiple-peak texture.Both sheets precipitate β'phase and CRA sheet exhibits a stronger aging response.The CRA sheet has higher yield strength and tensile strength than URA sheet,with reduced yield strength anisotropy but increased tensile strength anisotropy.Taking into account different strengthening mechanisms,although the finer grain size of URA sheet enhances grain boundary strengthening,CRA sheet is more responsive to aging,leading to superior aging-precipitated phase strengthening and consequently higher yield strength.展开更多
Al-Cu-Mg-Ag alloys have become a research hotspot because of its good heat resistance.Its excellent mechanical properties are inseparable from the regulation of the structure by researchers.The method of material stru...Al-Cu-Mg-Ag alloys have become a research hotspot because of its good heat resistance.Its excellent mechanical properties are inseparable from the regulation of the structure by researchers.The method of material structure simulation has become more and more perfect.This study employs numerical simulation to investigate the microstructure evolution of Al-Cu-Mg-Ag alloys during solidification with the aim of controlling its structure.The size distribution of Ti-containing particles in an Al-Ti-B master alloy was characterized via microstructure observation,serving as a basis for optimizing the nucleation density parameters for particles of varying radii in the phase field model.The addition of refiner inhibited the growth of dendrites and no longer produced coarse dendrites.With the increase of refiner,the grains gradually tended to form cellular morphology.The refined grains were about 100μm in size.Experimental validation of the simulated as-cast grain morphology was conducted.The samples were observed by metallographic microscope and scanning electron microscope.The addition of refiner had a significant effect on the refinement of the alloy,and the average grain size after refinement was also about 100μm.At the same time,the XRD phase identification of the alloy was carried out.The observation of the microstructure morphology under the scanning electron microscope showed that the precipitated phase was mainly concentrated on the grain boundary.The Al_(2)Cu accounted for about 5%,and the matrix phase FCC accounted for about 95%,which also corresponded well with the simulation results.展开更多
为了解十倍体长穗偃麦草5Ag染色体在不同小麦背景中的遗传稳定性及其在配子中的传递,本研究利用小麦-十倍体长穗偃麦草二体代换系DS5Ag(5D),即百农普偃5814(PY5814),与6个小麦品种(系)中国春、百农矮抗58、兰考矮早8、温麦6号、周麦16以...为了解十倍体长穗偃麦草5Ag染色体在不同小麦背景中的遗传稳定性及其在配子中的传递,本研究利用小麦-十倍体长穗偃麦草二体代换系DS5Ag(5D),即百农普偃5814(PY5814),与6个小麦品种(系)中国春、百农矮抗58、兰考矮早8、温麦6号、周麦16以及Q03073进行杂交,杂种F1自交,并分别与上述6个品种(系)进行正反交,利用分子标记技术对F2和BC1F1代进行鉴定。结果表明,PY5814与6个不同小麦品种(系)杂交获得的F1均能够正常结实;在不同组合的F2分离群体中,5Ag染色体传递率范围为51.61%~71.76%,表明5Ag染色体在不同小麦背景中的遗传率不同,传递受小麦背景的影响。在BC1F1群体中,5Ag染色体通过雌配子和雄配子的传递率范围分别为21.43%~31.73%和29.51%~39.73%,表明5Ag染色体可以通过雌、雄配子传递;在兰考矮早8和温麦6号背景下,其通过雄配子的传递率高于通过雌配子的传递率,表明其在遗传研究中适合做父本。同时利用基因组荧光原位杂交(GISH,genomic in situ hybridization)技术对部分F2材料进行了验证,其结果与分子标记结果一致。本研究还为构建适宜杂交群体规模的预测,从而在后代中有效筛选出携带5Ag染色体的目标单株提供了理论指导。展开更多
基金Project(2023GK2020)supported by the Key Research and Development Program of Hunan Province,China。
文摘Microstructure and mechanical properties of aged Mg-10Gd-2Y-0.4Zr-0.4Ag alloy sheets prepared by different rolling routes were investigated.The results showed that the cross rolling aged(CRA)sheet possesses larger grain size than unidirectional rolling aged(URA)sheet due to the occurrence of dynamic recovery during rolling which reduces the dislocation density and delays dynamic recrystallization(DRX).The URA sheet has basal texture and RD favored texture while CRA sheet has multiple-peak texture.Both sheets precipitate β'phase and CRA sheet exhibits a stronger aging response.The CRA sheet has higher yield strength and tensile strength than URA sheet,with reduced yield strength anisotropy but increased tensile strength anisotropy.Taking into account different strengthening mechanisms,although the finer grain size of URA sheet enhances grain boundary strengthening,CRA sheet is more responsive to aging,leading to superior aging-precipitated phase strengthening and consequently higher yield strength.
文摘Al-Cu-Mg-Ag alloys have become a research hotspot because of its good heat resistance.Its excellent mechanical properties are inseparable from the regulation of the structure by researchers.The method of material structure simulation has become more and more perfect.This study employs numerical simulation to investigate the microstructure evolution of Al-Cu-Mg-Ag alloys during solidification with the aim of controlling its structure.The size distribution of Ti-containing particles in an Al-Ti-B master alloy was characterized via microstructure observation,serving as a basis for optimizing the nucleation density parameters for particles of varying radii in the phase field model.The addition of refiner inhibited the growth of dendrites and no longer produced coarse dendrites.With the increase of refiner,the grains gradually tended to form cellular morphology.The refined grains were about 100μm in size.Experimental validation of the simulated as-cast grain morphology was conducted.The samples were observed by metallographic microscope and scanning electron microscope.The addition of refiner had a significant effect on the refinement of the alloy,and the average grain size after refinement was also about 100μm.At the same time,the XRD phase identification of the alloy was carried out.The observation of the microstructure morphology under the scanning electron microscope showed that the precipitated phase was mainly concentrated on the grain boundary.The Al_(2)Cu accounted for about 5%,and the matrix phase FCC accounted for about 95%,which also corresponded well with the simulation results.
文摘为了解十倍体长穗偃麦草5Ag染色体在不同小麦背景中的遗传稳定性及其在配子中的传递,本研究利用小麦-十倍体长穗偃麦草二体代换系DS5Ag(5D),即百农普偃5814(PY5814),与6个小麦品种(系)中国春、百农矮抗58、兰考矮早8、温麦6号、周麦16以及Q03073进行杂交,杂种F1自交,并分别与上述6个品种(系)进行正反交,利用分子标记技术对F2和BC1F1代进行鉴定。结果表明,PY5814与6个不同小麦品种(系)杂交获得的F1均能够正常结实;在不同组合的F2分离群体中,5Ag染色体传递率范围为51.61%~71.76%,表明5Ag染色体在不同小麦背景中的遗传率不同,传递受小麦背景的影响。在BC1F1群体中,5Ag染色体通过雌配子和雄配子的传递率范围分别为21.43%~31.73%和29.51%~39.73%,表明5Ag染色体可以通过雌、雄配子传递;在兰考矮早8和温麦6号背景下,其通过雄配子的传递率高于通过雌配子的传递率,表明其在遗传研究中适合做父本。同时利用基因组荧光原位杂交(GISH,genomic in situ hybridization)技术对部分F2材料进行了验证,其结果与分子标记结果一致。本研究还为构建适宜杂交群体规模的预测,从而在后代中有效筛选出携带5Ag染色体的目标单株提供了理论指导。
