The magnetic response, microstructural and texture changes occurring during cold rolling of a Fe-14Mn-0.64C-2.4AI-0.25Si medium stacking fault energy TWlP (twinning induced plasticity) steel have been studied by X-r...The magnetic response, microstructural and texture changes occurring during cold rolling of a Fe-14Mn-0.64C-2.4AI-0.25Si medium stacking fault energy TWlP (twinning induced plasticity) steel have been studied by X-ray diffraction and magnetic techniques. The changes in the sub-grain size (Ds), probability of stacking fault formation (Psf) and microstrain in the material as cold rolling progressed were determined by using a modified version of the Williamson and Hall equation. A strong development of the crystallographic texture with increasing deformation was observed. Deformation-induced formation of a small fraction α'-martensite was observed, indicating that the steel also exhibits γ→α'-martensite transformation during cold rolling, which is discussed via the changes of the stacking-fault probability and the texture development during cold rolling.展开更多
Optimization of the intermetallic layer thickness and the suppression of interfacial defects are key elements to improve the load bearing capacity of dissimilar joints. However, till date we do not have a systematic t...Optimization of the intermetallic layer thickness and the suppression of interfacial defects are key elements to improve the load bearing capacity of dissimilar joints. However, till date we do not have a systematic tool to investigate the dissimilar joints and the intermetallic properties produced by a welding condition. Friction Melt Bonding (FMB) is a recently developed technique for joining dissimilar metals that also does not exempt to these challenges. The FMB of DP980 and A16061-T6 was investigated using a new physical simulation tool, based on Gleeble thermo-mechanical simulator, to understand the effect of individual parameter on the intermetallic formation. The proposed method demonstrates its capability in reproducing the intermetallic characteristics, including the thickness of intermetallic bonding layer, the morphology and texture of its constituents (Fe2AU and Fe4Ali3), as well as their nanohardness and reduced modulus. The advantages of physical simulation tool can enable novel developing routes for the development of dissimilar metal joining processes and facilitate to reach the requiring load bearing capacity of the joints.展开更多
Some practical research topics on tunable fiber gratings in author's group are presented, including tuning speed, tuning range, tuning characteristics of gratings in HB fiber, and the tunability of the line-width....Some practical research topics on tunable fiber gratings in author's group are presented, including tuning speed, tuning range, tuning characteristics of gratings in HB fiber, and the tunability of the line-width. The applications of fiber gratings in communication and sensing are also discussed.展开更多
文摘The magnetic response, microstructural and texture changes occurring during cold rolling of a Fe-14Mn-0.64C-2.4AI-0.25Si medium stacking fault energy TWlP (twinning induced plasticity) steel have been studied by X-ray diffraction and magnetic techniques. The changes in the sub-grain size (Ds), probability of stacking fault formation (Psf) and microstrain in the material as cold rolling progressed were determined by using a modified version of the Williamson and Hall equation. A strong development of the crystallographic texture with increasing deformation was observed. Deformation-induced formation of a small fraction α'-martensite was observed, indicating that the steel also exhibits γ→α'-martensite transformation during cold rolling, which is discussed via the changes of the stacking-fault probability and the texture development during cold rolling.
基金financial support of FRIAfinancial support of the European Research Council for a starting grant under grant No. 716678Chinese Scientific Council for financial support (No. 201606890031)
文摘Optimization of the intermetallic layer thickness and the suppression of interfacial defects are key elements to improve the load bearing capacity of dissimilar joints. However, till date we do not have a systematic tool to investigate the dissimilar joints and the intermetallic properties produced by a welding condition. Friction Melt Bonding (FMB) is a recently developed technique for joining dissimilar metals that also does not exempt to these challenges. The FMB of DP980 and A16061-T6 was investigated using a new physical simulation tool, based on Gleeble thermo-mechanical simulator, to understand the effect of individual parameter on the intermetallic formation. The proposed method demonstrates its capability in reproducing the intermetallic characteristics, including the thickness of intermetallic bonding layer, the morphology and texture of its constituents (Fe2AU and Fe4Ali3), as well as their nanohardness and reduced modulus. The advantages of physical simulation tool can enable novel developing routes for the development of dissimilar metal joining processes and facilitate to reach the requiring load bearing capacity of the joints.
文摘Some practical research topics on tunable fiber gratings in author's group are presented, including tuning speed, tuning range, tuning characteristics of gratings in HB fiber, and the tunability of the line-width. The applications of fiber gratings in communication and sensing are also discussed.