Metal matrix composites tiles based on Ti-6Al-4V(Ti64)alloy,reinforced with 10,20,and 40(vol%)of either TiC or TiB particles were made using press-and-sinter blended elemental powder metallurgy(BEPM)and then bonded to...Metal matrix composites tiles based on Ti-6Al-4V(Ti64)alloy,reinforced with 10,20,and 40(vol%)of either TiC or TiB particles were made using press-and-sinter blended elemental powder metallurgy(BEPM)and then bonded together into 3-layer laminated plates using hot isostatic pressing(HIP).The laminates were ballistically tested and demonstrated superior performance.The microstructure and properties of the laminates were analyzed to determine the effect of the BEPM and HIP processing on the ballistic properties of the layered plates.The effect of porosity in sintered composites on further diffusion bonding of the plates during HIP is analyzed to understand the bonding features at the interfaces between different adjacent layers in the laminate.Exceptional ballistic performance of fabricated structures was explained by a significant reduction in the residual porosity of the BEPM products by their additional processing using HIP,which provides an unprecedented increase in the hardness of the layered composites.It is argued that the combination of the used two technologies,BEPM and HIP is principally complimentary for the materials in question with the abilities to solve the essential problems of each used individually.展开更多
(Gd,Lu)_(2)O_(3)∶Eu scintillation ceramics have promising applications in the high-energy X-ray imaging.Eu0.1Gd0.6Lu1.3O3 nano-powders with pure phase were prepared from the precursor calcined at 1050℃for 4 h by the...(Gd,Lu)_(2)O_(3)∶Eu scintillation ceramics have promising applications in the high-energy X-ray imaging.Eu0.1Gd0.6Lu1.3O3 nano-powders with pure phase were prepared from the precursor calcined at 1050℃for 4 h by the co-precipitation method.Using the synthesized nano-powders as initial material,Eu_(0.1)Gd_(0.6)Lu_(1.3)O_(3)ceramics were fabri-cated by vacuum pre-sintering at different temperatures for 2 h and hot isostatic pressing(HIP)at 1750℃for 3 h in ar-gon.The influence of pre-sintering temperature on the microstructure,optical and luminescence properties was investi-gated.The Eu_(0.1)Gd_(0.6)Lu_(1.3)O_(3)ceramics pre-sintered at 1625℃for 2 h combined with HIP post-treatment show the high-est in-line transmittance of 75.2%at 611 nm.The photoluminescence(PL)and X-ray excited luminescence(XEL)spectra of the Eu_(0.1)Gd_(0.6)Lu_(1.3)O_(3)transparent ceramics demonstrate a strong red emission peak at 611 nm due to the^(5)D_(0)→^(7)F_(2) transition of Eu^(3+).The PL,PLE and XEL intensities of the HIP post-treated Eu_(0.1)Gd_(0.6)Lu_(1.3)O_(3)ceramics show a trend of first ascending and then descending with the increase of pre-sintering temperature.The thermally stimulated lumines-cence(TSL)curve of the HIP post-treated Eu_(0.1)Gd_(0.6)Lu_(1.3)O_(3)ceramics presents one high peak at 178 K and two peaks with lower intensities at 253 K and 320 K.The peak at 320 K may be related to oxygen vacancies,and the lumines-cence peak at 178 K is related to defects caused by the valence state changes of Eu^(3+)ions.展开更多
粉末近净成形(Powder metallurgy near net shaping,PM-NNS)技术能够制备出具有优异综合力学性能的粉末合金复杂部件。介绍了粉末热等静压(Hot isostatic pressing,HIP)近净成形技术原理及优势,综述了近年来国内外粉末近净成形在航天发...粉末近净成形(Powder metallurgy near net shaping,PM-NNS)技术能够制备出具有优异综合力学性能的粉末合金复杂部件。介绍了粉末热等静压(Hot isostatic pressing,HIP)近净成形技术原理及优势,综述了近年来国内外粉末近净成形在航天发动机领域的研究现状,从工艺路线和构件研制两方面展开,简述了构件制备过程的影响因素及缺陷控制,结合中国科学院金属研究所粉末近净成形技术在航天发动机领域的研究及应用情况,总结了粉末近净成形技术当前存在的主要问题及发展方向,以期进一步拓宽该技术的应用范围。展开更多
采用夹杂物含量水平不同的两批次粉末,通过相同的热等静压制度制备了FGH97合金,研究了夹杂物对FGH97合金力学性能的影响。对比测试了两组粉末制备FGH97合金的拉伸性能,表征了粉末特征、合金组织、拉伸断口。结果表明,采用真空惰性气体雾...采用夹杂物含量水平不同的两批次粉末,通过相同的热等静压制度制备了FGH97合金,研究了夹杂物对FGH97合金力学性能的影响。对比测试了两组粉末制备FGH97合金的拉伸性能,表征了粉末特征、合金组织、拉伸断口。结果表明,采用真空惰性气体雾化(Vacuum induction melting gas atomization,VIGA)法制备的粉末,细粉收集率高,制备的合金晶粒细小,容易引入夹杂物。富Si的异常颗粒夹杂会使合金中产生贫γ′区,影响粉末间的结合,降低FGH97合金的塑性。热等静压态的FGH97合金室温延伸率为9.5%,650℃的延伸率为1%。FGH97合金经过固溶+时效热处理后,基体中的贫γ′区消失,FGH97合金的塑性得到显著提升,FGH97合金室温延伸率提升至14.25%,650℃的延伸率提升至6%。展开更多
基金funding from the NATO Agency Science for Peace and Security (#G5787)Ballistic investigations were co-financed by Military University of Technology in Warsaw under research project UGB 829/2023/WATSeparate works made in G.V.Kurdyumov Institute for Metal Physics of N.A.S.of Ukraine were partially financially supported by N.A.S.of Ukraine within the frames of project#III09-18。
文摘Metal matrix composites tiles based on Ti-6Al-4V(Ti64)alloy,reinforced with 10,20,and 40(vol%)of either TiC or TiB particles were made using press-and-sinter blended elemental powder metallurgy(BEPM)and then bonded together into 3-layer laminated plates using hot isostatic pressing(HIP).The laminates were ballistically tested and demonstrated superior performance.The microstructure and properties of the laminates were analyzed to determine the effect of the BEPM and HIP processing on the ballistic properties of the layered plates.The effect of porosity in sintered composites on further diffusion bonding of the plates during HIP is analyzed to understand the bonding features at the interfaces between different adjacent layers in the laminate.Exceptional ballistic performance of fabricated structures was explained by a significant reduction in the residual porosity of the BEPM products by their additional processing using HIP,which provides an unprecedented increase in the hardness of the layered composites.It is argued that the combination of the used two technologies,BEPM and HIP is principally complimentary for the materials in question with the abilities to solve the essential problems of each used individually.
文摘(Gd,Lu)_(2)O_(3)∶Eu scintillation ceramics have promising applications in the high-energy X-ray imaging.Eu0.1Gd0.6Lu1.3O3 nano-powders with pure phase were prepared from the precursor calcined at 1050℃for 4 h by the co-precipitation method.Using the synthesized nano-powders as initial material,Eu_(0.1)Gd_(0.6)Lu_(1.3)O_(3)ceramics were fabri-cated by vacuum pre-sintering at different temperatures for 2 h and hot isostatic pressing(HIP)at 1750℃for 3 h in ar-gon.The influence of pre-sintering temperature on the microstructure,optical and luminescence properties was investi-gated.The Eu_(0.1)Gd_(0.6)Lu_(1.3)O_(3)ceramics pre-sintered at 1625℃for 2 h combined with HIP post-treatment show the high-est in-line transmittance of 75.2%at 611 nm.The photoluminescence(PL)and X-ray excited luminescence(XEL)spectra of the Eu_(0.1)Gd_(0.6)Lu_(1.3)O_(3)transparent ceramics demonstrate a strong red emission peak at 611 nm due to the^(5)D_(0)→^(7)F_(2) transition of Eu^(3+).The PL,PLE and XEL intensities of the HIP post-treated Eu_(0.1)Gd_(0.6)Lu_(1.3)O_(3)ceramics show a trend of first ascending and then descending with the increase of pre-sintering temperature.The thermally stimulated lumines-cence(TSL)curve of the HIP post-treated Eu_(0.1)Gd_(0.6)Lu_(1.3)O_(3)ceramics presents one high peak at 178 K and two peaks with lower intensities at 253 K and 320 K.The peak at 320 K may be related to oxygen vacancies,and the lumines-cence peak at 178 K is related to defects caused by the valence state changes of Eu^(3+)ions.
文摘粉末近净成形(Powder metallurgy near net shaping,PM-NNS)技术能够制备出具有优异综合力学性能的粉末合金复杂部件。介绍了粉末热等静压(Hot isostatic pressing,HIP)近净成形技术原理及优势,综述了近年来国内外粉末近净成形在航天发动机领域的研究现状,从工艺路线和构件研制两方面展开,简述了构件制备过程的影响因素及缺陷控制,结合中国科学院金属研究所粉末近净成形技术在航天发动机领域的研究及应用情况,总结了粉末近净成形技术当前存在的主要问题及发展方向,以期进一步拓宽该技术的应用范围。
文摘采用夹杂物含量水平不同的两批次粉末,通过相同的热等静压制度制备了FGH97合金,研究了夹杂物对FGH97合金力学性能的影响。对比测试了两组粉末制备FGH97合金的拉伸性能,表征了粉末特征、合金组织、拉伸断口。结果表明,采用真空惰性气体雾化(Vacuum induction melting gas atomization,VIGA)法制备的粉末,细粉收集率高,制备的合金晶粒细小,容易引入夹杂物。富Si的异常颗粒夹杂会使合金中产生贫γ′区,影响粉末间的结合,降低FGH97合金的塑性。热等静压态的FGH97合金室温延伸率为9.5%,650℃的延伸率为1%。FGH97合金经过固溶+时效热处理后,基体中的贫γ′区消失,FGH97合金的塑性得到显著提升,FGH97合金室温延伸率提升至14.25%,650℃的延伸率提升至6%。
