Synthesis of Low-cost Titanium Alloys with Wrought-like Mechanical Properties by Sintering Blended Elemental Powder in Pressure-less Vacuum
A major problem with the use of Ti is its high cost.Powder metallurgy(PM)has long been regarded as a promising method to reduce the cost of Ti alloys,owing to its near-net-shape capabilities,fine and homogenous microstructure.In present work,the feasibility of producing Ti-6Al-4V with full densification and forged-like mechanical properties by sintering blended elemental(BE)powder in pressure-less vacuum is comprehensive investigated.The raw materials are Ti sponge,Al-V master alloy and Al powder.Blend powders with an irregular shape of approximately 3-20 μm are manufactured via hydrogenation,crushing and dehydrogenation.Then,the cold isostatic pressing and vacuum sintering are employed to produce the Ti-6Al-4V ingots.The homogeneous basket-weave microstructure with lath-like α grains and α+β lamellae of different orientation and the density of 99.5%are obtained by sintering at 1150℃.And the as-sintered Ti-6Al-4V shows an optimum mechanical property(UTS=945±12 MPa,YS=876±10 MPa,EL=15.5±0.6%).The chemical composition of samples especially interstitial elements(O=0.14 wt%,N=0.33 wt%,H=0.008 wt%)meets the standard values for wrought Ti-6Al-4V in ASTM-B381.It means that traditional PM can achieve high performance Ti alloys while keeping the cost low without resorting to thermomechanical processing.
Titanium alloys Blended elemental Vacuum pressure-less sintering Relative density Mechanical properties Microstructure
Zhang Ce Guo Zhimeng Lu Boxin Wang Haiying
Institute for Advanced Materials and Technology,University of Science and Technology Beijing,30 Xueyuan Road,Beijing 100083,China
国际会议
北京
英文
969-973
2018-09-16（万方平台首次上网日期，不代表论文的发表时间）