The microstructure and texture of Mo–La2O3 alloys with high transverse ductility

Abstract

The properties and microstructure of Mo–La2O3 bars were investigated during hot upsetting deformation. The properties can be improved by increasing the reduction of upsetting deformation. After upset by 90%, the transverse elongation and microhardness of Mo–La2O3 bars are up to 7.5% and 266HV, respectively. The main texture components of 〈100〉 fiber and 〈111〉 fiber are formed in Mo–La2O3 bars during upsetting process. After upset by 90%, the orientation density of 〈100〉 fiber and 〈111〉 fiber reaches 4.54 and 8.17 times random respectively. Meanwhile, homogenous and fine elongated subgrains are formed in Mo–La2O3 bars. Ductile failures can be seen after transverse bending. A typical laminate fracture presents and lots of dimples can be seen on the laminate layers. The size of these dimples is about 0.5μm, which is the same as that of subgrains. The fracture model is also proposed.