Hot isostatic pressing parameters are critical to Ti60 high temperature titanium alloy castings which have wide application perspective in aerospace.In order to obtain optimal processing parameters,the effects of hot ...Hot isostatic pressing parameters are critical to Ti60 high temperature titanium alloy castings which have wide application perspective in aerospace.In order to obtain optimal processing parameters,the effects of hot isostatic pressing parameters on defects,composition uniformity,microstructure and mechanical properties of Ti60 cast high temperature titanium alloy were investigated in detail.Results show that increasing temperature and pressure of hot isostatic pressing can reduce defects,especially,the internal defects are substantially eliminated when the temperature exceeds 920℃or the pressure exceeds 125 MPa.The higher temperature and pressure can improve the microstructure uniformity.Besides,the higher pressure can promote the composition uniformity.With the temperature increases from 880℃to 960℃,α-laths are coarsened.But with increasing pressure,the grain size of prior-βphase,the widths ofα-laths andα-colony are reduced.The tensile strength of Ti60 alloy is 949 MPa,yield strength is 827 MPa,and the elongation is 11%when the hot isostatic pressing parameters are 960℃/125 MPa/2 h,which exhibits the best match between the strength and plasticity.展开更多
Effects of welding parameters on the microstructure and mechanical properties of Ti/Cu/Ni joint welded by electron beam were investigated.High welding heat input increased the melting quantity of Ti60 titanium alloy a...Effects of welding parameters on the microstructure and mechanical properties of Ti/Cu/Ni joint welded by electron beam were investigated.High welding heat input increased the melting quantity of Ti60 titanium alloy and promoted the formation of Ti-Cu intermetallic compounds(IMC)such as Ti_(2)Cu and Ti_(3)Cu_(4),increasing the brittleness of the joints.Low welding heat input was not conducive to the complete melting of the copper interlayer,and the unmelted copper reduced the performance of the joints.Under the optimal welding parameters,Ti-Ni IMCs in the weld would be replaced by(Cu,Ni)solid solutions((Cu,Ni)_(ss)).However,Ti-Cu IMC layers cannot be eliminated entirely by changing the welding parameters.The maximum tensile strength of the joints was 201 MPa.The fracture of the joints occurred at the Ti-Cu IMC layer,which was a typical brittle fracture.展开更多
基金financially supported by the National Key Research and Development Program of China(Grant No.2020YFB2008300)。
文摘Hot isostatic pressing parameters are critical to Ti60 high temperature titanium alloy castings which have wide application perspective in aerospace.In order to obtain optimal processing parameters,the effects of hot isostatic pressing parameters on defects,composition uniformity,microstructure and mechanical properties of Ti60 cast high temperature titanium alloy were investigated in detail.Results show that increasing temperature and pressure of hot isostatic pressing can reduce defects,especially,the internal defects are substantially eliminated when the temperature exceeds 920℃or the pressure exceeds 125 MPa.The higher temperature and pressure can improve the microstructure uniformity.Besides,the higher pressure can promote the composition uniformity.With the temperature increases from 880℃to 960℃,α-laths are coarsened.But with increasing pressure,the grain size of prior-βphase,the widths ofα-laths andα-colony are reduced.The tensile strength of Ti60 alloy is 949 MPa,yield strength is 827 MPa,and the elongation is 11%when the hot isostatic pressing parameters are 960℃/125 MPa/2 h,which exhibits the best match between the strength and plasticity.
基金supported by Shandong Provincial Key Research and Development Program of China(2019JZZY010439)。
文摘Effects of welding parameters on the microstructure and mechanical properties of Ti/Cu/Ni joint welded by electron beam were investigated.High welding heat input increased the melting quantity of Ti60 titanium alloy and promoted the formation of Ti-Cu intermetallic compounds(IMC)such as Ti_(2)Cu and Ti_(3)Cu_(4),increasing the brittleness of the joints.Low welding heat input was not conducive to the complete melting of the copper interlayer,and the unmelted copper reduced the performance of the joints.Under the optimal welding parameters,Ti-Ni IMCs in the weld would be replaced by(Cu,Ni)solid solutions((Cu,Ni)_(ss)).However,Ti-Cu IMC layers cannot be eliminated entirely by changing the welding parameters.The maximum tensile strength of the joints was 201 MPa.The fracture of the joints occurred at the Ti-Cu IMC layer,which was a typical brittle fracture.
