Pre-alloyed powder of Ti-22Al-24Nb-0.5Mo（atomic fraction,%） was prepared by gas atomization.Powder metallurgy（PM） Ti 2AlNb alloys were prepared by a hot isostatic pressing（HIPing） route.The influence of experime...Pre-alloyed powder of Ti-22Al-24Nb-0.5Mo（atomic fraction,%） was prepared by gas atomization.Powder metallurgy（PM） Ti 2AlNb alloys were prepared by a hot isostatic pressing（HIPing） route.The influence of experimental variables including HIPing temperatures,solution and aging temperatures on microstructure and properties of PM Ti 2AlNb alloys was studied.The results showed that HIPing temperature affected the porosity distribution and mechanical properties of PM Ti 2AlNb alloys.The microstructure and mechanical properties of the PM Ti 2AlNb alloys changed obviously after various post heat treatments,and a good combination of tensile strength,ductility and rupture lifetime was obtained through an optimized heat treatment in the present work.展开更多
In this work, hot isostatic pressing （HIPing） technique was used to densify the Ti2AINb pre-alloyed powder. The influence of HIPing loading route parameters （temperature and rates of heating and pressurizing） on m...In this work, hot isostatic pressing （HIPing） technique was used to densify the Ti2AINb pre-alloyed powder. The influence of HIPing loading route parameters （temperature and rates of heating and pressurizing） on microstructure and properties of PM Ti2AINb alloys was studied. The results showed that HIPing loading route parameters affected the densification process and mechanical properties （especially high temper- ature rupture lifetime） of PM Ti2AINb alloys in the present work. A finite element method （FEM） model for predicting the final densification was developed and was used to optimize the HIPing procedure.展开更多
The present work reports the effect of thermal induced porosity(TIP)on the high-cycle fatigue(HCF)and very high-cycle fatigue(VHCF)behaviors of hot-isostatic-pressed(HIPed)Ti-6Al-4V alloy from gasatomized powder.The r...The present work reports the effect of thermal induced porosity(TIP)on the high-cycle fatigue(HCF)and very high-cycle fatigue(VHCF)behaviors of hot-isostatic-pressed(HIPed)Ti-6Al-4V alloy from gasatomized powder.The results show that the residual pores in the as-HIPed powder compacts present no obvious effect on the HCF life.The regrowth of the residual pores can be observed after solution heat treatment.The pore location ranks the most harmful for the fatigue life compared with the other initiating defects.The maximum stress intensity factors were calculated.The plastic zone size of fine granular area(FGA)is much less than the characteristic size of the microstructure,and the crucial size of the internal pores in this study is about 40μm.The failure types of fatigue specimens in the VHCF regime were classified,and the competition of different failure types was described based on the modified Poisson distribution.展开更多
文摘Pre-alloyed powder of Ti-22Al-24Nb-0.5Mo（atomic fraction,%） was prepared by gas atomization.Powder metallurgy（PM） Ti 2AlNb alloys were prepared by a hot isostatic pressing（HIPing） route.The influence of experimental variables including HIPing temperatures,solution and aging temperatures on microstructure and properties of PM Ti 2AlNb alloys was studied.The results showed that HIPing temperature affected the porosity distribution and mechanical properties of PM Ti 2AlNb alloys.The microstructure and mechanical properties of the PM Ti 2AlNb alloys changed obviously after various post heat treatments,and a good combination of tensile strength,ductility and rupture lifetime was obtained through an optimized heat treatment in the present work.
文摘In this work, hot isostatic pressing （HIPing） technique was used to densify the Ti2AINb pre-alloyed powder. The influence of HIPing loading route parameters （temperature and rates of heating and pressurizing） on microstructure and properties of PM Ti2AINb alloys was studied. The results showed that HIPing loading route parameters affected the densification process and mechanical properties （especially high temper- ature rupture lifetime） of PM Ti2AINb alloys in the present work. A finite element method （FEM） model for predicting the final densification was developed and was used to optimize the HIPing procedure.
基金financially supported by the Natural Science Foundation of Shanxi Province,China(No.201901D211085)the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(STIP)
文摘The present work reports the effect of thermal induced porosity(TIP)on the high-cycle fatigue(HCF)and very high-cycle fatigue(VHCF)behaviors of hot-isostatic-pressed(HIPed)Ti-6Al-4V alloy from gasatomized powder.The results show that the residual pores in the as-HIPed powder compacts present no obvious effect on the HCF life.The regrowth of the residual pores can be observed after solution heat treatment.The pore location ranks the most harmful for the fatigue life compared with the other initiating defects.The maximum stress intensity factors were calculated.The plastic zone size of fine granular area(FGA)is much less than the characteristic size of the microstructure,and the crucial size of the internal pores in this study is about 40μm.The failure types of fatigue specimens in the VHCF regime were classified,and the competition of different failure types was described based on the modified Poisson distribution.
