The secondary hardening, the austenite grain coarsening and the surface decarburization phenomenon of Nb-bearing spring steel were investigated, and the effects of niobium on tempered microstructure was studied using ...The secondary hardening, the austenite grain coarsening and the surface decarburization phenomenon of Nb-bearing spring steel were investigated, and the effects of niobium on tempered microstructure was studied using scanning electron microscope. The results show that the micro-addition of niobium increases the tempering resistance and produces secondary hardening. The effect of niobium on the size and distribution of cementite particles is one of the primary reasons to increase the hardness after tempering. The grain-coarsening temperature of the spring steel is raised 150 ~C due to Nb-addition. Furthermore, both the secondary hardening and the austenite grain coarsening phenomenon congruously demonstrate niobium begins observably dissolving above 1 100 ℃ in the spring steel. Be- sides, niobium microalloying is an effective and economy means to decrease the decarburization sensitivity of the spring steels.展开更多
In this paper,three different roughening route planning methods(free coarsening,vertical coarsening,circling coarsening)were designed to pre-treat the basement membrane.The platinum IPMC was prepared by electroless pl...In this paper,three different roughening route planning methods(free coarsening,vertical coarsening,circling coarsening)were designed to pre-treat the basement membrane.The platinum IPMC was prepared by electroless plating to observe their surface morphology and test their performances such as output displacement and blocking force.The results show that the platinum electrode of the vertical coarsening route planning of IPMC is distributed in the shape of fish scales and is the most compact and regular on the surface electrode.The thickness of the platinum electrode layer is about 13μm,the maximum output displacement is 54.89 mm,the blocking force of 15.46 mN,and the maximum strain energy density of the IPMC of 2.44 KJ/m^(3).Vertical coarsening route planning can significantly improve the electrodynamic properties of IPMC,and it is recommended that the surface roughening of IPMC be utilized in the research and application of IPMC.It lays a certain experimental foundation for the performance improvement and innovation research and development of IPMC in the subsequent stage.展开更多
基金Sponsored by CITIC-CBMM Niobium Steel Research and Development Projects of China(2007RMJS-D031)
文摘The secondary hardening, the austenite grain coarsening and the surface decarburization phenomenon of Nb-bearing spring steel were investigated, and the effects of niobium on tempered microstructure was studied using scanning electron microscope. The results show that the micro-addition of niobium increases the tempering resistance and produces secondary hardening. The effect of niobium on the size and distribution of cementite particles is one of the primary reasons to increase the hardness after tempering. The grain-coarsening temperature of the spring steel is raised 150 ~C due to Nb-addition. Furthermore, both the secondary hardening and the austenite grain coarsening phenomenon congruously demonstrate niobium begins observably dissolving above 1 100 ℃ in the spring steel. Be- sides, niobium microalloying is an effective and economy means to decrease the decarburization sensitivity of the spring steels.
基金financially supported by the Key Science and Technology Program of Shaanxi Province,China[2016KTZDGY-02-03].
文摘In this paper,three different roughening route planning methods(free coarsening,vertical coarsening,circling coarsening)were designed to pre-treat the basement membrane.The platinum IPMC was prepared by electroless plating to observe their surface morphology and test their performances such as output displacement and blocking force.The results show that the platinum electrode of the vertical coarsening route planning of IPMC is distributed in the shape of fish scales and is the most compact and regular on the surface electrode.The thickness of the platinum electrode layer is about 13μm,the maximum output displacement is 54.89 mm,the blocking force of 15.46 mN,and the maximum strain energy density of the IPMC of 2.44 KJ/m^(3).Vertical coarsening route planning can significantly improve the electrodynamic properties of IPMC,and it is recommended that the surface roughening of IPMC be utilized in the research and application of IPMC.It lays a certain experimental foundation for the performance improvement and innovation research and development of IPMC in the subsequent stage.