Carbothermal/aluminothermic reduction nitridation synthesis of ZrN–SiAlON refractory composites from zircon and bauxite: a comparative study of the reduction effect of reducers

Abstract The rainfall runoff reduction effect on green roofs was analyzed and tested by comparative rainfall runoff monitoring on impermeable roofs (sloping, plane). The evaluation index of rainfall runoff interception benefit (relative runoff reduction rate, rainfall control rate) on green roofs was studied. The results show that compared with sloping and level roofs, the change range of green roof runoff reduction rate relative to level and sloping roofs is 20.0–98.3% and 3.8–92.3%, and the mean value is 48.4% and 34.3% respectively. It is obvious that the green roof has better rainfall runoff reduction effect. It can be seen from the single rainfall control effect that the variation range of green roof rainfall runoff control rate is 36.0% to 99.0%, and the total rainfall control rate is 57.6%, which reflects that the green roof has the better rainfall control effect. Through comparative study, it can be concluded that the rainfall runoff control rate is more suitable for the design index of green roofs.

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A Comparative Study of SHS Synthesis of TiB2 Cermets Powder by Magnesium Reduction and Aluminothermy Reduction

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.567.33 ◽

2012 ◽

Vol 567 ◽

pp. 33-36

Author(s):

Hai Bo Wang ◽

Xi Bao Wang ◽

Hui Li

Keyword(s):

Comparative Study ◽

Reduction Reaction ◽

Impurity Phase ◽

Aluminothermic Reduction ◽

Metal Reduction ◽

Reaction Products ◽

Pickling Process ◽

Arc Heating

In this paper, metal reduction preparation of TiB2 powder via magnesium reduction and aluminothermic reduction were studied. The carbon rod arc heating generated from the spread of the reaction of TiB2，and then the examinations were performed after pickling, crushing and grinding such as SEM and XRD. The results showed that the aluminothermic reduction occurred into the powder impurity phase less, but the need for better technology separation of Al2O3. Magnesium reduction reaction products with more impurities, pickling process removes only the reactants of MgO and other impurities not removed in the air and impurities were analyzed and compared.

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Preparation and Mechanical Properties of TiN-Al2O3 Refractory Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.833.217 ◽

2013 ◽

Vol 833 ◽

pp. 217-220

Author(s):

Hai Tao Liu ◽

Ming Hao Fang ◽

Zhao Hui Huang ◽

Hai Peng Ji ◽

Xin Min ◽

...

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Flexural Strength ◽

Bulk Density ◽

Sintering Temperature ◽

Aluminothermic Reduction ◽

Pressureless Sintering ◽

Densification Behaviour ◽

Effects Of Temperature ◽

Refractory Composites

TiN-Al2O3 bulk composites were prepared by pressureless sintering of the as-synthesized powder products obtained by aluminothermic reduction-nitridation of aluminum dross and rutile. The effects of temperature on the densification behaviour and mechanical properties of TiN-Al2O3 composites were studied. Results showed that the bulk density of the TiN-Al2O3 composites increased with the elevated sintering temperature. When the temperature arrived at 1500 °C, the flexural strength and fracture toughness reached the highest values (201.48 MPa and 4.11 MPa·m1/2, respectively).

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