A new high throughput heat-treatment method with a continuous temperature gradient between 600 and 700 ?C was utilized on the Ti-5553 alloy(Ti-5 Al-5 Mo-5 V-3 Cr, mass fraction, %). The temperature gradient was ind...A new high throughput heat-treatment method with a continuous temperature gradient between 600 and 700 ?C was utilized on the Ti-5553 alloy(Ti-5 Al-5 Mo-5 V-3 Cr, mass fraction, %). The temperature gradient was induced by the variation of the axial section of sample, which was heated by the direct current. The variation of continuous cooling rates on the treated sample was realized by using the end quenching method. The microstructural evolution and mechanical properties under different heat treatment conditions were evaluated. The results show that the pseudo-spinodal decomposition of the alloy occurs at(617±1) ?C, and the size of the precipitated α phase is around 300 nm. Moreover, the highest microhardness is obtained after the heat treatment at the pseudo-spinodal decomposition temperature for 4 h. These indicate that the high throughput method is efficient and fast to determine the phase transformation temperature and corresponding microstructural evolution of alloys.展开更多
Let¢ : Nn x [0,∞) -4 [0, ∞) be a function such that ¢(x,.) is an Orlicz function and ¢(.,t) ∈ Aloc∞(Nn) (the class of local weights introduced by Rychkov). In this paper, the authors introduce a loca...Let¢ : Nn x [0,∞) -4 [0, ∞) be a function such that ¢(x,.) is an Orlicz function and ¢(.,t) ∈ Aloc∞(Nn) (the class of local weights introduced by Rychkov). In this paper, the authors introduce a local Musielak-Orlicz Hardy space h¢(Nn) by the local grand maximal function, and a local BMO-type space bmo¢(Nn) which is further proved to be the dual space of h¢(Nn). As an application, the authors prove that the class of pointwise multipliers for the local BMO-type space bmo¢(Nn), characterized by Nakai and Yabuta, is just the dual of LI(Rn) + hФ0 (Rn), where Ф is an increasing function on (0, co) satisfying some additional growth conditions and Ф0 a Musielak-Orlicz function induced by Ф. Characterizations of h¢(Rn), including the atoms, the local vertical and the local nontangential maximal functions, are presented. Using the atomic char- acterization, the authors prove the existence of finite atomic decompositions achieving the norm in some dense subspaces of h¢(Rn), from which, the authors further deduce some criterions for the boundedness on h¢(Rn) of some sublinear operators. Finally, the authors show that the local Riesz transforms and some pseudo-differential operators are bounded on h¢(Rn).展开更多
基金Project(2014CB644002)supported by the National Basic Research and Development Project of ChinaProject(2015CX004)supported by the Innovation-driven Plan in Central South University,China
文摘A new high throughput heat-treatment method with a continuous temperature gradient between 600 and 700 ?C was utilized on the Ti-5553 alloy(Ti-5 Al-5 Mo-5 V-3 Cr, mass fraction, %). The temperature gradient was induced by the variation of the axial section of sample, which was heated by the direct current. The variation of continuous cooling rates on the treated sample was realized by using the end quenching method. The microstructural evolution and mechanical properties under different heat treatment conditions were evaluated. The results show that the pseudo-spinodal decomposition of the alloy occurs at(617±1) ?C, and the size of the precipitated α phase is around 300 nm. Moreover, the highest microhardness is obtained after the heat treatment at the pseudo-spinodal decomposition temperature for 4 h. These indicate that the high throughput method is efficient and fast to determine the phase transformation temperature and corresponding microstructural evolution of alloys.
基金supported by National Natural Science Foundation of China(Grant No.11171027)Program for Changjiang Scholars and Innovative Research Team in University of China
文摘Let¢ : Nn x [0,∞) -4 [0, ∞) be a function such that ¢(x,.) is an Orlicz function and ¢(.,t) ∈ Aloc∞(Nn) (the class of local weights introduced by Rychkov). In this paper, the authors introduce a local Musielak-Orlicz Hardy space h¢(Nn) by the local grand maximal function, and a local BMO-type space bmo¢(Nn) which is further proved to be the dual space of h¢(Nn). As an application, the authors prove that the class of pointwise multipliers for the local BMO-type space bmo¢(Nn), characterized by Nakai and Yabuta, is just the dual of LI(Rn) + hФ0 (Rn), where Ф is an increasing function on (0, co) satisfying some additional growth conditions and Ф0 a Musielak-Orlicz function induced by Ф. Characterizations of h¢(Rn), including the atoms, the local vertical and the local nontangential maximal functions, are presented. Using the atomic char- acterization, the authors prove the existence of finite atomic decompositions achieving the norm in some dense subspaces of h¢(Rn), from which, the authors further deduce some criterions for the boundedness on h¢(Rn) of some sublinear operators. Finally, the authors show that the local Riesz transforms and some pseudo-differential operators are bounded on h¢(Rn).