Quantitative relations between blowhole and coating components of stainless steel electrode

Using uniform design method and computer program, the experiment has been arranged, the mathematical model between blowhole resistance of stainless steel electrode and 12 coating components has been regressed. And the trend diagrams of effects of. every ingredient on the blowhole resistance have been drawn out. The mathematical model and trend diagrams revealed the complex laws between the mark of blowhole resistance and coating components. The effect of each ingredient on the mark of blowhole resistance is different, such as the mark of blowhole resistance increases with calcite increases. There are interactions among the coating components, such as the mark of blowhole resistance decreases with fluorite increases when calcite content is lower; but it increases when calche content is higher. The sieving and forecasting can be done using mathematical model and computer program.

Droplet transfer behavior of the stainless steel coated electrode with double-layer coating

In this paper, the droplet transfer behavior of the stainless steel coated electrode with double layer coating is researched by means of those experimental methods, such as high speed camera, collecting droplet in water, surfacing on the steel plate et al. The results show that the droplet transfer indexes of coated electrode are mainly controlled by the size of droplet, which affects the transfer behavior of droplet. The distribution characteristic of the droplet size of the electrode affects the numerical relationship among droplet transfer indexes. The metallurgical process of the coated electrode with double layer coating is carried out continuously in different zones. The main reason for the coated electrode with double layer coating gaining excellent usability quality is that the droplets realize the 'quasi flux wall guided transfer pattern'.

Treatment of tannery wastewater by electrocoagulation

Treatment of tannery wastewater by electrocoagulation with low cell current （≤ 1A） and soluble electrodes （mild steel electrodes and aluminum electrodes） was studied. Compared with aluminum electrodes, mild steel electrodes were more effective for the removal of sulfide, with a removal efficiency of over 90%. But during the treatment process, black color precipitate typical to iron（Ⅱ） sulfides was produced. While aluminum electrodes were effective to eliminate the colority of the effluent, the removal efficiency of sulfide was lower than 12%. The mechanisms of the removal of chemical oxygen demand, ammonia, total organic carbon, sulfide and colority with the two soluble electrodes （mild steel and aluminum electrodes） were discussed in detail. In order to exert the predominance of diffenent types of electrodes, the tannery wastewater was treated using mild steel electrodes first followed by the filter and finally by the aluminum electrodes, the elimination rates of chemical oxygen demand, ammonia, total organic carbon, sulfide and colority were 68.0%, 43.1%, 55.1%, 96.7% and 84.3%, respectively, with the initial concentrations 2413.1 mg/L, 223.4 mg/L, 1000.4 mg/L, 112.3 mg/L and 256 dilution times, respectively. The absorbance spectra and energy consumption during electrocoagulation process were also discussed.

Effects of rare earth elements on sulphur and phosphorus impurities in deposited metal

In order to reduce sulphur （ S ） and phosphorus （ P ） impurities in deposited metal, a small amount of rare earth （RE） lanthanum （ La） and yttrium （Y） were added into the coating ofE4303 electrode, a low carbon steel electrode. The microstructures of deposited metal were analyzed with metalloscope, and then the content of S and P was examined by energy dispenive X-ray spectrometer （ EDXS ）, and by wavelength dispersive X-ray fluorescence （XRF） spectrometer for further examination. The results show that the proper addition of La and Y can be beneficial to the desulfurization and dephosphorization of the deposited metal. Certainly, difference in the addition amount of La and Y could lead to various desulfurization and dephosphorization efficiency, in which the former is more obvious than the latter. With the proper amount of La attd Y, there is finer microstructure in deposited metal, and mechanical properties are improved as well. The S content in deposited metal with added La and Y decreases by 44. 44 wt. % , while the P content 6. 67 wt. %, compared with that in deposited metal without La and II.

Study of porosity tendency in the Cr-Ni austenitic weld based on inclusion’s characteristic in the droplet

The effect of nonmetallic inclusions in the droplet of the stainless steel covered electrode on the porosity was researched.The result shows that the nonmetallic inclusions in the droplet are spherical,their composition is different from the one of slag and the inclusions have the character of “inner formation”.When the ratio of rutile to ilmenite in the coated material is increased, the droplet becomes coarse, the content of nonmetallic inclusion in the droplet decreases,and the porosity sensitivity in the weld metal also decreases.When the ratio of fledspar to ilmenite in the coated material is increased, the droplet becomes fine,the content of nonmetallic inclusion in the droplet increases, and the porosity sensitivity in the weld metal increases. When the ratio of Fe_2O_3 to ilmenite in the coated material is increased, the droplet becomes fine, the content of nonmetallic inclusion decreases, while the porosity sensitivity does not reduce.