采用电场压力激活辅助合成工艺(Field activated and pressure assisted synthesis process (FAPAS))制备铜基石墨烯复合材料,研究不同的石墨烯含量对铜基体材料的微观结构和性能的影响机理。结果表明,石墨烯的添加能提高材料的位错密...采用电场压力激活辅助合成工艺(Field activated and pressure assisted synthesis process (FAPAS))制备铜基石墨烯复合材料,研究不同的石墨烯含量对铜基体材料的微观结构和性能的影响机理。结果表明,石墨烯的添加能提高材料的位错密度、阻止位错在晶界移动,硬度提升17.6%;由于石墨烯添加量少,对铜基复合材料的位错密度和晶粒尺寸影响有限,片状的石墨烯能有效地弥补制备产生的缺陷,使材料的热导率和电导率分别提升2.9%和4.4%;石墨烯的添加使腐蚀电池两极间的电位差减小,降低了铜离子在氧化膜中的扩散能力,使复合材料的阻抗提升5.3%,腐蚀电流密度下降28.2%,有效地提升了铜基复合材料的耐腐蚀性能。铜基石墨烯复合材料的石墨烯最佳添加量为0.5 wt.%。展开更多
High manganese twinning-induced plasticity （TWIP） steel is a new kind of structural material and possesses both high strength and superior plasticity and can meet the weight-lightening requirement for manufacturing ...High manganese twinning-induced plasticity （TWIP） steel is a new kind of structural material and possesses both high strength and superior plasticity and can meet the weight-lightening requirement for manufacturing vehicle body. The excellent formability of the TWIP steel comes from the extraordinary strain hardening effect during plastic deformation. The reduction of specific weight by aluminum alloying and strain hardening effect can lead to an effective weight reduction of the steel components, and provide a better choice for materials in vehicle body design. The TWIP effect in high Mn steels is generally associated with the successive work- hardening generated by twins and influenced by some factors, such as Mn content, AI addition revealed by stacking fault energy （SFE）, grain size, deformation temperature and strain rate. The present review introduces some aspects of the TWIP steels relating to their physical metallurgy, influencing factors associated with their deformation mechanisms, and a prospect for the future investigation is also described. Moreover, as a potential candidate for replacing Ni-Cr austenitic stainless steel, researches on the oxidation behavior and corrosion resistance of Fe-Mn-AI-C system steels are also reviewed.展开更多
Zn is a commonly used alloying element for Mg alloys owing to its beneficial effects on mechanical properties. To improve the mechanical and corrosion properties of WE43B Mg alloys, the effects of 0–0.7wt% Zn additio...Zn is a commonly used alloying element for Mg alloys owing to its beneficial effects on mechanical properties. To improve the mechanical and corrosion properties of WE43B Mg alloys, the effects of 0–0.7wt% Zn addition on the microstructure and properties of sample alloys were investigated. Addition of Zn to as-cast WE43B alloy promoted the formation of the Mg12Nd phase;by contrast, after T6 heat treatment, the phase composition of WE43B alloys with and without Zn addition remained mostly the same. A long-period stacking ordered phase was predicted by CALPHAD calculation, but this phase was not observed in either the as-cast or heat-treated Zn-containing WE43B alloys. The optimum temperature and duration of T6 heat treatment were obtained using CALPHAD calculations and hardness measurements. Addition of Zn resulted in a slight reduction in the average grain size of the as-cast and T6 heat-treated WE43B alloys and endowed them with increased corrosion resistance with little effect on their mechanical properties.展开更多
文摘采用电场压力激活辅助合成工艺(Field activated and pressure assisted synthesis process (FAPAS))制备铜基石墨烯复合材料,研究不同的石墨烯含量对铜基体材料的微观结构和性能的影响机理。结果表明,石墨烯的添加能提高材料的位错密度、阻止位错在晶界移动,硬度提升17.6%;由于石墨烯添加量少,对铜基复合材料的位错密度和晶粒尺寸影响有限,片状的石墨烯能有效地弥补制备产生的缺陷,使材料的热导率和电导率分别提升2.9%和4.4%;石墨烯的添加使腐蚀电池两极间的电位差减小,降低了铜离子在氧化膜中的扩散能力,使复合材料的阻抗提升5.3%,腐蚀电流密度下降28.2%,有效地提升了铜基复合材料的耐腐蚀性能。铜基石墨烯复合材料的石墨烯最佳添加量为0.5 wt.%。
基金supported by the Fundamental Research Funds for the Central Universities (No. N100507003)
文摘High manganese twinning-induced plasticity （TWIP） steel is a new kind of structural material and possesses both high strength and superior plasticity and can meet the weight-lightening requirement for manufacturing vehicle body. The excellent formability of the TWIP steel comes from the extraordinary strain hardening effect during plastic deformation. The reduction of specific weight by aluminum alloying and strain hardening effect can lead to an effective weight reduction of the steel components, and provide a better choice for materials in vehicle body design. The TWIP effect in high Mn steels is generally associated with the successive work- hardening generated by twins and influenced by some factors, such as Mn content, AI addition revealed by stacking fault energy （SFE）, grain size, deformation temperature and strain rate. The present review introduces some aspects of the TWIP steels relating to their physical metallurgy, influencing factors associated with their deformation mechanisms, and a prospect for the future investigation is also described. Moreover, as a potential candidate for replacing Ni-Cr austenitic stainless steel, researches on the oxidation behavior and corrosion resistance of Fe-Mn-AI-C system steels are also reviewed.
基金financial support from the Ministry of Education and Science of the Russian Federation, Agreement No. 03.G25.31.0274 (27 May 2017)
文摘Zn is a commonly used alloying element for Mg alloys owing to its beneficial effects on mechanical properties. To improve the mechanical and corrosion properties of WE43B Mg alloys, the effects of 0–0.7wt% Zn addition on the microstructure and properties of sample alloys were investigated. Addition of Zn to as-cast WE43B alloy promoted the formation of the Mg12Nd phase;by contrast, after T6 heat treatment, the phase composition of WE43B alloys with and without Zn addition remained mostly the same. A long-period stacking ordered phase was predicted by CALPHAD calculation, but this phase was not observed in either the as-cast or heat-treated Zn-containing WE43B alloys. The optimum temperature and duration of T6 heat treatment were obtained using CALPHAD calculations and hardness measurements. Addition of Zn resulted in a slight reduction in the average grain size of the as-cast and T6 heat-treated WE43B alloys and endowed them with increased corrosion resistance with little effect on their mechanical properties.
