NCS Testing Technology Co.

Beijing, China

NCS Testing Technology Co.

Beijing, China
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Fan L.-X.,Beijing General Research Institute of Mining And Metallurgy | Fan L.-X.,Beijing Key Laboratory for Evaluation and Testing of Metallic Mineral Resources | Lu Q.,Central Iron&Steel Research Institute | Lu Q.,NCS Testing Technology Co.
Yejin Fenxi/Metallurgical Analysis | Year: 2017

The sample was dissolved with hydrofluoric acid-hydrochloric acid-nitric acid-perchloric acid system. Lead was separated in the form of lead sulfate precipitate, which was then dissolved in ammonia-EDTA solution medium. The content of lead was finally determined by lead acetate back titration method in HAc-NaAc buffer solution using xylenol orange as the indicator. The experimental conditions, including the ageing time of precipitate, the addition amount of ammonia, the sub-boiling time and the dosage of HAc-NaAc buffer solution, were optimized. The determination method of lead in lead glass by EDTA back titration was established. The proposed method was applied to the determination of lead in lead glass. The relative standard deviations (RSD, n=11) of determination result was 0.32%. The recovery test of lead glass sample was conducted according to the experimental method. The recoveries were between 99.5% and 102.0%. © 2017, CISRI Boyuan Publishing Co., Ltd. All right reserved.


Lu Q.,Control Iron and Steel Research Institute, China | Lu Q.,NCS Testing Technology Co. | Fan L.-X.,Beijing General Research Institute of Mining And Metallurgy | Li J.-Q.,University of Science and Technology Beijing
Yejin Fenxi/Metallurgical Analysis | Year: 2017

The sample was digested with the mixed acid combined with 5.0 mL of hydrofluoric acid and 10.0 mL of nitric acid. Ce 407.570 nm, Cu 217.895 nm, Fe 234.350 nm, Er 390.631 nm, Mg 383.829 nm, Mn 257.610 nm, Pb 283.305 nm and Zn 213.857 nm were selected as analytical lines. Consequently, an analysis method of eight elements (including Ce, Cu, Fe, Er, Mg, Mn, Pb and Zn) in molybdenum-niobium alloy by inductively coupled plasma atomic emission spectrometry (ICP-AES) was established. The influence of major elements (Mo, Nb and Al) on test elements was investigated. The results indicated that these elements had no significant influence on determination. The linear correlation coefficients of calibration curves were all higher than 0.999. The detection limits of elements were between 5.4 μg/g and 63 μg/g. The proposed method was applied for the determination of Ce, Cu, Fe, Er, Mg, Mn, Pb and Zn in molybdenum-niobium alloy samples. The relative standard deviations (RSD, n=6) were between 0.89% and 4.4%. The recoveries were between 98% and 102%. The content of Ce, Cu, Fe, Er, Mg, Mn, Pb and Zn in molybdenum-niobium alloy samples was determined according to the experimental method. The results were consistent with those obtained by inductively coupled plasma mass spectrometry (ICP-MS). © 2017, CISRI Boyuan Publishing Co., Ltd. All right reserved.


Fan L.-X.,Beijing General Research Institute of Mining And Metallurgy | Fan L.-X.,Beijing Key Laboratory for Evaluation and Testing of Metallic Mineral Resources | Lu Q.,Control Iron and Steel Research Institute, China | Lu Q.,NCS Testing Technology Co.
Yejin Fenxi/Metallurgical Analysis | Year: 2017

The high content lead in sample is usually determined by EDTA titration after lead sulfate precipitate separation. However, the interference of tin and bismuth cannot be ignored when the method is applied for the determination of lead content in crude tin. The sample was dissolved in PTFE beaker with hydrochloric acid-nitric acid-perchloric acid and hydrochloric acid-nitric acid-hydrobromic acid. Under the experimental conditions, the tin in sample could react with hydrobromic acid to form stannic bromide, which would be removed through volatilization. After treatment by lead sulfate precipitate separation, the mercaptoacetic acid was added into solution before titration to mask bismuth. The determination method of lead in crude tin by EDTA titration was established in HAc-NaAc buffer solution using xylenol orange as the indicator. The experimental conditions were further optimized, including the ageing time of precipitate, the dosage of HAc-NaAc buffer solution and the slight boiling time. The optimum conditions were finally obtained as follows: the ageing time was 2 h, the dosage of HAc-NaAc buffer solution at pH 5.5-6.0 was 30 mL, and the slight boiling time was 10 min. The proposed method was applied for the determination of lead in crude tin, and the found results were consistent with those obtained by inductively coupled plasma atomic emission spectrometry (ICP-AES). The relative standard deviation (RSD, n=11) was 0.68% and 0.38%, respectively. The recoveries of standard addition were between 98% and 102%. © 2017, CISRI Boyuan Publishing Co., Ltd. All right reserved.


Li X.,Zhenjiang Siyang Special Metal Material Manufacture Co. | Bian J.,Zhenjiang Siyang Special Metal Material Manufacture Co. | Liu P.,NCS Testing Technology Co.
Tezhong Zhuzao Ji Youse Hejin/Special Casting and Nonferrous Alloys | Year: 2015

Microstructure of copper alloy ingot was analyzed by ultrasonic testing combined with metallographic observation. The results reveal that two kinds of shrinkage porosities easily occurs in the forging parts, and they demonstrate different ultrasonic waveform characteristics and microscopic form, which provides effective information to determine the shrinkage porosities for subsequent ultrasonic testing. By analyzing the origination of two kinds of shrinkage porosities, the defects in copper alloy ingot casting were eliminated by modifying casting process, and the yield rate of the copper alloy casting was improved greatly. ©, 2015, Journal Office of Special Casting and Nonferrous Alloys. All right reserved.


Zhou D.Q.,University of Science and Technology Beijing | Zhao W.X.,University of Science and Technology Beijing | Mao H.H.,KTH Royal Institute of Technology | Hu Y.X.,University of Science and Technology Beijing | And 3 more authors.
Materials Science and Engineering A | Year: 2015

In this paper, the dynamic evolution of precipitates and its influence on the high-temperature mechanical properties of newly developed AFA steels were systematically investigated. At 1023K or above, three main types of precipitates, i.e., the B2-NiAl, Laves-Fe2Nb, and δ/σ phases, were formed in the base steel, and the major strengthening medium is Laves-Fe2Nb, which coarsened quickly, leading to undesirable creep properties. Phase competition between the most effective strengthening NbC nanosized precipitates and the Laves-Fe2Nb phase was analyzed, and it was found that adjusting the Nb/C ratio in the steels could enable the precipitation of highly stable, fine NbC particles. In addition, the formation of detrimental σ phases could be suppressed by lowering the Mo and Si content in the alloy. Eventually, a new type of AFA steel consisting of a high density of nanosized NbC particles homogeneously dispersed in the austenitic matrix was successfully developed, and significant enhancement in the creep resistance was achieved due to the effective strengthening resulting from the tiny secondary NbC particles. © 2014 Elsevier B.V.


Li X.-H.,Shandong Xiangguang Copper Co. | Wan S.,Shandong Xiangguang Copper Co. | Liu Z.-J.,Shandong Liaocheng Entry Exit Inspection and Quarantine Bureau | Guo F.-F.,NCS Testing Technology Co.
Yejin Fenxi/Metallurgical Analysis | Year: 2016

The content range of calibration curve was broadened using certified reference material of copper concentrate and adding spectral-purity substance or standard solution of single element. The sample was prepared by fusion method. The content of copper, lead, chromium, arsenic, silver, antimony, bismuth, nickel, iron and aluminum in copper concentrate was determined by wavelength dispersive X-ray fluorescence spectrometry(XRF). The fusion conditions were obtained by experiments and listed as follows: the lithium tetraborate-lithium metaborate mixed flux (m:m=33:67) was used; the dilution ratio was 1:20; the pre-oxidization time was 5 min; the pre-oxidization temperature was 700℃; the fusion time was 10 min; the fusion temperature was 1 000-1 050℃ ; the silicon dioxide was used as glassing reagent; 3-4 drops of 500 g/L lithium bromide solution was used as releasing reagent. The interference of coexisting elements and spectral overlapping could be corrected by theoretical influence coefficient method. The detection limits were between 12 μg/g and 156 μg/g. The precision test was conducted using one copper concentrate sample. The relative standard deviations (RSD, n=11) of determination results of testing elements were between 0.19% and 11.3%. The found results of three actual copper concentrate samples were consistent with those obtained by standard analysis method. The proposed method could meet the requirements of rapid analysis of copper concentrate samples. © 2016, CISRI Boyuan Publishing Co., Ltd. All right reserved.


Chen J.Y.,Beijing Institute of Technology | Li Q.,Beijing Institute of Technology | Li J.,NCS Testing Technology Co. | Tang X.,Beijing Institute of Technology | Xiao C.B.,Beijing Institute of Technology
Materials Science Forum | Year: 2016

The effects of Co additions on the evolution of γ’ precipitates and topologically close-packed (TCP) phases during thermal exposure at 950 °C were investigated for two Ni-based single crystal superalloys with 7.9 wt.% Co and 9.1 wt.% Co. The results indicated that the γ′ morphology was not affected by Co content, whereas γ′ volume fraction decreased and precipitate size increased due to lower Co addition after standard heat treatment. The coarsening of γ′ precipitates in both alloys was controlled by diffusion. The γ′ coarsening rate increased, while the stability of γ′ volume fraction decreased due to lower level of Co addition during 950 °C thermal exposure because more Co addition suppressed the diffusion process. High Co addition promoted the formation of μ phase after thermal exposure at 950 °C for 1000 h due to higher γ′ volume fraction, more stable γ′ volume fraction and higher electron vacancy number. The experimental results of μ phase precipitation showed good agreement with thermodynamic calculation by JMatPro. © 2016 Trans Tech Publications, Switzerland.


Shi Y.,NCS Testing Technology Co.
Key Engineering Materials | Year: 2016

A combination study of magnetic and magnetostrictive properties in directionally cast and differently heat-treated Fe-20Ga(at.%) samples has been carried out at room temperature. Slow cooling leads to an increase in the occupation of [200] easy magnetic axes; however, a structural ordering of Ga atoms into a metastable D03 phase decreasesthe saturation magnetostriction (λs) and the saturation magnetization (Ms), and increases coercivity (Hc). Our results confirm the contribution of D03 ordering to magnetic and magnetostrictive properties due to their pinning effects against magnetic domain wall motions. As compared to slow cooling, water quenching suppresses the formation of metastable (D03) or stable (L12) ordered phases and preserves the A2 single phase structure down to room temperature, leading to enhanced magnetostriction and magnetization. © 2016 Trans Tech Publications, Switzerland.


Zhao H.-Y.,NCS Testing Technology Co. | Qi R.,NCS Testing Technology Co. | Hou Y.-X.,NCS Testing Technology Co. | Zhou X.-X.,NCS Testing Technology Co.
Yejin Fenxi/Metallurgical Analysis | Year: 2016

The sample was dissolved by hydrochloric acid and nitric acid. After removing carbon by perchloric acid fume, the content of arsenic, copper and zinc in lead concentrate was determined in 20% (V/V) acid medium by inductively coupled plasma atomic emission spectrometry (ICP-AES) using As 188.980 nm, Cu 327.395 nm and Zn 328.233 nm as analytical lines. The results showed that the determination results of arsenic, copper and zinc were not significantly affected by matrix effect. The calibration curves were prepared by lead-free matrix matching method. The linear correlation coefficients of calibration curves were higher than 0.9998. The detection limit of arsenic, copper and zinc was 0.0327 mg/L, 0.0240 mg/L and 0.130 mg/L, respectively. The arsenic, copper and zinc in lead concentrate standard sample were determined according to the experimental method. The relative standard deviations (RSD, n=7) were between 0.64% and 1.1%. The found results were consistent with the certified values and those obtained by alkali fusion ICP-AES. © 2016, CISRI Boyuan Publishing Co., Ltd. All right reserved.


Hou H.-X.,NCS Testing Technology Co. | Guo F.-F.,NCS Testing Technology Co. | Yang Q.-Q.,NCS Testing Technology Co.
Yejin Fenxi/Metallurgical Analysis | Year: 2015

The experimental conditions for the determination of nitrogen content in recarburizer by pulse heating inert gas fusion-thermal conductivity method were optimized. It was found that the recarburizer samples must be dried in oven at 100-110 ℃ after preparation. Moreover, the samples after grinding should be treated with 120 μm sieve. The optimized analytical power of instrument was 4.5 kW. The nickel foil should be used as flux to fully release the nitrogen in sample. The standard coal sample with similar composition and structure to the recarburizer was used to plot the calibration curve of nitrogen. The linear correlation coefficient was R2=0.993.The detection limit of nitrogen was 0.000 06%. The low limit of determination was 0.000 2%. The precision test of recarburizer sample was conducted, and the relative standard deviation (RSD, n=7) was not more than 3.4%. The actual samples were determined by the proposed method, and the found results were consistent with those obtained by pulse fusion-time of flight mass spectrometry. © 2015, Central Iron and Steel Research Institute. All right reserved.

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