The leaching process of magnesiothermic self-propagating product generated during the multistage deep reduction process was investigated.The influence of magnesiothermic self-propagating product particle size,HCl solu...The leaching process of magnesiothermic self-propagating product generated during the multistage deep reduction process was investigated.The influence of magnesiothermic self-propagating product particle size,HCl solution concentration,and leaching solution temperature on the leaching behavior of elements Al and V was investigated.Results demonstrate that the leaching rate of Al and V is increased with the rise in leaching solution temperature,the increase in HCl solution concentration,and the enlargement of magnesiothermic self-propagating product particle size.The leaching processes of Al and V are consistent with the chemical reaction control model.When the magnesiothermic self-propagation product with D_(50) of 59.4μm is selected as the raw material,the leaching temperature is 40℃,and 1 mol/L HCl solution is employed,after leaching for 180 min,the leaching rates of Al and V are 24.8%and 12.6%,respectively.The acid-leached product exhibits a porous structure with a specific surface area of 3.5633 m^(2)/g.展开更多
Experimental tests are essential for evaluating S-N curves and assessing the fatigue life of welded joints.However,in the case of complex geometries,experimental tests often cannot provide the necessary stress-strain ...Experimental tests are essential for evaluating S-N curves and assessing the fatigue life of welded joints.However,in the case of complex geometries,experimental tests often cannot provide the necessary stress-strain data for specific materials and welded joints.Therefore,finite element(FE)analyses are frequently utilized to assess fatigue behavior in complex geometries and address the discontinuities induced by welding processes.In this study,the fatigue properties of titanium welded joints,produced using an innovative laser source and welded without the use of filler materials,were analyzed through numerical methods.Two different FEmethodswere applied to T-specimens fabricated from Ti6Al4V sheets:the hot-spot stress and notch-stress approach.The FE fatigue life predictions were validated using experimental fatigue test results.The Hot-Spot Stress method yielded a fatigue limit slightly below 100 MPa,demonstrating a consistent slope in the S-N response.Conversely,the Notch Stress method,using a 1 mm fictitious notch radius,indicated a higher fatigue strength corresponding to a range between 225 and 250MPa,providing amore conservative and localized fatigue estimate.Fatigue resistance in welded joints of steel and aluminum is commonly assessed using specific fatigue classes called“Fatigue Strength Classes(FAT)curves”and their associated S-N curves as recommended by the International Institute of Welding(IIW).However,no such FAT class assignments currently exist for titanium alloys.To address this gap,strain-based FAT curves were proposed by normalizing steel FAT curves using titanium’s elastic properties.This strain-based framework enables direct comparison across materials and provides a foundation for fatigue evaluation of titanium weldments.The author proposed a procedure to normalize steel FAT curves considering the different elastic material properties,enabling a comparison with Ti6Al4V data in terms of hot spot strain or notch strain.This approach facilitates the development of a universal framework for strain-based fatigue evaluation across different materials.展开更多
基金Scientific and Technological Project of Nanyang(23KJGG017)Key Specialized Research&Development and Promotion Project(Scientific and Technological Project)of Henan Province(232102221022)+1 种基金College Students and Technology Innovation Fund Project of Nanyang Institute of Technology(2023139)Project of Doctoral Scientific Research Startup Fund of Nanyang Institute of Technology(NGBJ-2023-25)。
文摘The leaching process of magnesiothermic self-propagating product generated during the multistage deep reduction process was investigated.The influence of magnesiothermic self-propagating product particle size,HCl solution concentration,and leaching solution temperature on the leaching behavior of elements Al and V was investigated.Results demonstrate that the leaching rate of Al and V is increased with the rise in leaching solution temperature,the increase in HCl solution concentration,and the enlargement of magnesiothermic self-propagating product particle size.The leaching processes of Al and V are consistent with the chemical reaction control model.When the magnesiothermic self-propagation product with D_(50) of 59.4μm is selected as the raw material,the leaching temperature is 40℃,and 1 mol/L HCl solution is employed,after leaching for 180 min,the leaching rates of Al and V are 24.8%and 12.6%,respectively.The acid-leached product exhibits a porous structure with a specific surface area of 3.5633 m^(2)/g.
基金supported by the project PRIN_2022PNRR_P2022Y3PBY_001“MADLEINE,CUP:J53D23015830001”.Project funded under the National Recovery and Resilience Plan(NRRP),Mission 4 Component C2 Investment 1.1 by the European Union-NextGenerationEU.
文摘Experimental tests are essential for evaluating S-N curves and assessing the fatigue life of welded joints.However,in the case of complex geometries,experimental tests often cannot provide the necessary stress-strain data for specific materials and welded joints.Therefore,finite element(FE)analyses are frequently utilized to assess fatigue behavior in complex geometries and address the discontinuities induced by welding processes.In this study,the fatigue properties of titanium welded joints,produced using an innovative laser source and welded without the use of filler materials,were analyzed through numerical methods.Two different FEmethodswere applied to T-specimens fabricated from Ti6Al4V sheets:the hot-spot stress and notch-stress approach.The FE fatigue life predictions were validated using experimental fatigue test results.The Hot-Spot Stress method yielded a fatigue limit slightly below 100 MPa,demonstrating a consistent slope in the S-N response.Conversely,the Notch Stress method,using a 1 mm fictitious notch radius,indicated a higher fatigue strength corresponding to a range between 225 and 250MPa,providing amore conservative and localized fatigue estimate.Fatigue resistance in welded joints of steel and aluminum is commonly assessed using specific fatigue classes called“Fatigue Strength Classes(FAT)curves”and their associated S-N curves as recommended by the International Institute of Welding(IIW).However,no such FAT class assignments currently exist for titanium alloys.To address this gap,strain-based FAT curves were proposed by normalizing steel FAT curves using titanium’s elastic properties.This strain-based framework enables direct comparison across materials and provides a foundation for fatigue evaluation of titanium weldments.The author proposed a procedure to normalize steel FAT curves considering the different elastic material properties,enabling a comparison with Ti6Al4V data in terms of hot spot strain or notch strain.This approach facilitates the development of a universal framework for strain-based fatigue evaluation across different materials.
