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Lanthanum-doped titanium-zirconium-molybdenum (La-TZM) alloy was prepared by powder metallurgy and rolling process. The processing crack and crack initiation mechanisms of La-TZM alloy after sintering, hot rolling and cold rolling were studied by scanning and transmission electron microscopy. The results show that the doped La(NO 3 ) 3 , TiH 2 and ZrH 2 have finer secondary phase in the La-TZM alloy plate. The fracture mode of sintering billet is inter-granular, but the fracture surface of hot rolling exhibited transgranular cleavage. However, the cold rolling is quasi-cleavage fracture. The secondary phase particles tend to hinder the movement of dislocations causing dislocations pile-up. The resulting tensile stress can accelerate cracks nucleation and growth, and the crack propagation will be deflected by the secondary phase particles. The crack initiation can be avoided by reducing local stress concentration caused by dislocations. [ABSTRACT FROM AUTHOR]

Pure molybdenum sheets were prepared by powder metallurgy and unidirectional rolling process. The microstructure, texture, grain orientation, mechanical properties and fracture mechanism of sintered samples were investigated. The results show that tensile strength and microhardness of 95% rolled sheet are 1028.095 ± 19.32 MPa and 323.2 ± 11.68 HV. The main texture components of (011)〈110〉 is Goss texture with reduction in the range of 70–95%. Two grain orientations of 〈111〉 fiber & 〈100〉 fiber and 〈100〉 fiber & 〈110〉 fiber are formed in the 47% and 95% rolled molybdenum sheets, respectively. Meanwhile, the fiber structure become more refined and oriented in the rolled molybdenum sheets when the rolling reduction is >87%. Brittle characteristics show typical cleavage failure. • Tensile strength and microhardness of 95% rolled sheet are 1028.095±19.32 MPa and 323.2±11.68 HV. • The main texture intensity value of Goss texture is 9.52 in the 95% rolled sheet. • Two grain orientations of <111> fiber & <100> fiber and <100> fiber & <110> fiber are formed in the 47% and 95% rolled molybdenum sheets, respectively. [ABSTRACT FROM AUTHOR]