摘要
The mechanical property and microstructure of a mechanically alloyed ( MA) oxide dispersionstrengthened (ODS) nickel-base superalloy MA758 have been investigated by compresion testing and mi-croscopy techniques. The yield strength of the as-extruded fine grain material is extremely significantly de-pendent on temperature, dropping from 880 MPa at 560℃ down to 15 MPa at 1160℃. The yield attain also drops with temperature, from 0. 037 at 560℃ to 0. 024 at 1160℃. The second part of the current research has revealed large amount of strap of Al_2O_3 particles forming after high temperature annealing inair, aligned along the extrusion direction. Upon annealing in vacuum, such particles do not form, thoughTi/Cr nitrides and carbides are present in small quantities. This phenomenon explains the hoed weaktransverse mechanical property in several ODS alloys.
The mechanical property and microstructure of a mechanically alloyed ( MA) oxide dispersionstrengthened (ODS) nickel-base superalloy MA758 have been investigated by compresion testing and mi-croscopy techniques. The yield strength of the as-extruded fine grain material is extremely significantly de-pendent on temperature, dropping from 880 MPa at 560℃ down to 15 MPa at 1160℃. The yield attain also drops with temperature, from 0. 037 at 560℃ to 0. 024 at 1160℃. The second part of the current research has revealed large amount of strap of Al_2O_3 particles forming after high temperature annealing inair, aligned along the extrusion direction. Upon annealing in vacuum, such particles do not form, thoughTi/Cr nitrides and carbides are present in small quantities. This phenomenon explains the hoed weaktransverse mechanical property in several ODS alloys.
