The complex metallic alloy（CMA）, Al（76.8）Fe（24）, was in-situ synthesized in the Al-based hybrid composite by powder metallurgy technique. The structural analysis by X-ray diffraction, scanning electron microscop...The complex metallic alloy（CMA）, Al（76.8）Fe（24）, was in-situ synthesized in the Al-based hybrid composite by powder metallurgy technique. The structural analysis by X-ray diffraction, scanning electron microscopy,and transmission electron microscopy indicated that the Al（76.8）Fe（24） CMA phase was formed by diffusion of Fe atoms into the Al matrix during the sintering stage. The formation of the CMA phase was mainly determined by the sintering temperature which was just above the eutectic temperature of Al–Fe. Moreover,the fully dense Al-based hybrid composite was obtained and exhibited ultrahigh strength ～1100 MPa,indicating that this method is expected to be effective in producing CMA particle reinforced Al-based hybrid composite.展开更多
The present study couples the acid/basis titration and the ICP analysis in order to monitor the concentrations of nitric and hydrofluoric acids, and presents into baths used to pickle alloys of titanium or stainless s...The present study couples the acid/basis titration and the ICP analysis in order to monitor the concentrations of nitric and hydrofluoric acids, and presents into baths used to pickle alloys of titanium or stainless steel, largely employed in the aeronautic industry. The pickling of the alloys releases various metallic cations able to react with HF in order to lead to metal-fluoride complexes and free H+, the last being able to react with the basis. In this study, it was determined: the most significant correlations providing the number of the protons released by the complexation of the metallic cation by the fluoride. The proposed method based on: 1) these correlations;2) the titration pH = f(VKOH) curves;and 3) the content of metallic cations determined by ICP, enables the monitoring of the content of HNO3 and HF into the pickling bath. Assuming that one bath was used for one type of alloy (alloys of Titanium for example, or alloys of stainless steel), then the proposed method appears providing reliable concentration values of both acids as well as metallic cations.展开更多
基金the financial support from the State Key Laboratory of Traction Power (Grant No. 2015TPL Z01)the State Key Laboratory of Solidification Processing (Grant Nos. 82TZ-2013 and SKLSP201609)+1 种基金the Fundamental Research Funds for the Central Universities (Grant No. 2682015RC07)the “111” Project (Grant No. B08040)
文摘The complex metallic alloy（CMA）, Al（76.8）Fe（24）, was in-situ synthesized in the Al-based hybrid composite by powder metallurgy technique. The structural analysis by X-ray diffraction, scanning electron microscopy,and transmission electron microscopy indicated that the Al（76.8）Fe（24） CMA phase was formed by diffusion of Fe atoms into the Al matrix during the sintering stage. The formation of the CMA phase was mainly determined by the sintering temperature which was just above the eutectic temperature of Al–Fe. Moreover,the fully dense Al-based hybrid composite was obtained and exhibited ultrahigh strength ～1100 MPa,indicating that this method is expected to be effective in producing CMA particle reinforced Al-based hybrid composite.
文摘The present study couples the acid/basis titration and the ICP analysis in order to monitor the concentrations of nitric and hydrofluoric acids, and presents into baths used to pickle alloys of titanium or stainless steel, largely employed in the aeronautic industry. The pickling of the alloys releases various metallic cations able to react with HF in order to lead to metal-fluoride complexes and free H+, the last being able to react with the basis. In this study, it was determined: the most significant correlations providing the number of the protons released by the complexation of the metallic cation by the fluoride. The proposed method based on: 1) these correlations;2) the titration pH = f(VKOH) curves;and 3) the content of metallic cations determined by ICP, enables the monitoring of the content of HNO3 and HF into the pickling bath. Assuming that one bath was used for one type of alloy (alloys of Titanium for example, or alloys of stainless steel), then the proposed method appears providing reliable concentration values of both acids as well as metallic cations.
