Ti6A14V alloy parts were prepared by metal injection molding. Brown parts were densified at 1 200-1 260℃for 2-4 h in vacuum atmosphere. The as-sintered specimens were treated through Hot-Isostatic Pressure(HIP) at 96...Ti6A14V alloy parts were prepared by metal injection molding. Brown parts were densified at 1 200-1 260℃for 2-4 h in vacuum atmosphere. The as-sintered specimens were treated through Hot-Isostatic Pressure(HIP) at 960℃and 140 MPa. Ti6A14V alloy compacts were annealed at 720-760℃for 1 h. The results show that binder in the parts can be removed by solvent debinding and thermal debinding process. Ti6A14V alloy has an uniform duplex microstructure with many equiaxedαgrains and a littleβgrains. When the annealing temperature is higher than 800℃, T16A14V alloy has lower mechanical properties.After solution treatment and aging, a typical martensite microstructure can be achieved.展开更多
Ti-6Al-4V compacts were fabricated by metal injection molding(MIM). Influence of vacuum sintering time on mechanical properties and microstructure of the sintered compacts at 1 260 ℃ were investigated. The experiment...Ti-6Al-4V compacts were fabricated by metal injection molding(MIM). Influence of vacuum sintering time on mechanical properties and microstructure of the sintered compacts at 1 260 ℃ were investigated. The experimental results show that the compacts sintered at 1 260 ℃ for 36 h, which was made from hydrogenation-dehydrogenation(HDH) powder(average particles size is 45 μm), have a relative density of 95.6% 96.7%, ultimate tensile strength of 648686MPa and 0.2% yield strength of 526615MPa; but a lower elongation(<4%) and that the compacts sintered at 1 260 ℃ for 26 h, which was made from 90% gas-atomized powder(average particles size is 32.5 μm) and 10% HDH powder, have higher relative density(>95%), ultimate tensile strength of 800848MPa, 0.2% yield strength of 712762MPa and high elongation (7.4%9.5%). When the sintering time is increased, porosity decreases and microstructure of sintered products changes from equiaxed to typical Widmanstatten, the average sizes of prior β grains, α colonies and α phase thickness in the β grains increase accordingly. After HIP treatment, pores obviously become less, microstructure of alloy is refined and mechanical properties are greatly improved.展开更多
文摘Ti6A14V alloy parts were prepared by metal injection molding. Brown parts were densified at 1 200-1 260℃for 2-4 h in vacuum atmosphere. The as-sintered specimens were treated through Hot-Isostatic Pressure(HIP) at 960℃and 140 MPa. Ti6A14V alloy compacts were annealed at 720-760℃for 1 h. The results show that binder in the parts can be removed by solvent debinding and thermal debinding process. Ti6A14V alloy has an uniform duplex microstructure with many equiaxedαgrains and a littleβgrains. When the annealing temperature is higher than 800℃, T16A14V alloy has lower mechanical properties.After solution treatment and aging, a typical martensite microstructure can be achieved.
文摘Ti-6Al-4V compacts were fabricated by metal injection molding(MIM). Influence of vacuum sintering time on mechanical properties and microstructure of the sintered compacts at 1 260 ℃ were investigated. The experimental results show that the compacts sintered at 1 260 ℃ for 36 h, which was made from hydrogenation-dehydrogenation(HDH) powder(average particles size is 45 μm), have a relative density of 95.6% 96.7%, ultimate tensile strength of 648686MPa and 0.2% yield strength of 526615MPa; but a lower elongation(<4%) and that the compacts sintered at 1 260 ℃ for 26 h, which was made from 90% gas-atomized powder(average particles size is 32.5 μm) and 10% HDH powder, have higher relative density(>95%), ultimate tensile strength of 800848MPa, 0.2% yield strength of 712762MPa and high elongation (7.4%9.5%). When the sintering time is increased, porosity decreases and microstructure of sintered products changes from equiaxed to typical Widmanstatten, the average sizes of prior β grains, α colonies and α phase thickness in the β grains increase accordingly. After HIP treatment, pores obviously become less, microstructure of alloy is refined and mechanical properties are greatly improved.
