Effect of Boron and Cerium on Microstructures and Properties of Cu-Fe-P Alloy

The effects of B and Ce on the removal of inclusions, microstructures, and properties of Cu-Fe-P alloys were studied. Certain impurity elements and the microstructures, mechanical properties, and conductivity of four experimental alloys, Cu-0.22Fe-0.06P, Cu-0.22Fe-0.06P-0.05Ce, Cu-0.22Fe-0.06P-0.02B, and Cu-0.22Fe-0.06P-0.05Ce-0. 02B （ %, mass fraction）, were tested and analyzed. Results show that on one hand, B and Ce have a remarkable function of removing S, Pb, and Bi from copper alloys ; on the other hand, the recrystallization temperature of the Cu-Fe-P alloy is considerably increased by adding trace B and Ce, resulting in the combined strengthening effect of precipitation hardening and cold work hardening after cold working and aging, while the negative effect of B and Ce on conductivity is slight. Therefore, a good combination of high strength and conductivity is achieved.     

Analysis and forecast of the supply and demand of electric power and its operation situation

Earlier May, China Electricity Council made forecast to the nationwide power supply and demand for the 2nd quarter of 2007 .     

Kinetics and mechanism of oxidation of β-sialons

Conclusions We examined the behavior of two materials during high-temperature oxidation: the singlephase -sialon and the material based on -sialon containing up to 8% residual -Si₃N₄ and the glass phase produced by reaction sintering of the charge based on -modification of silicon nitride. The results show that the maximum oxidation resistance in the temperature range 800–1300°C is exhibited by the single-phase -sialon Si_5.5Al_0.5O_0.5N_7.5. The oxidation resistance decreases in the presence of the residual -Si₃N₄ and the glass phase in the material. The oxidation kinetics are also determined by the structure and composition of the oxide film. The kinetic curves are governed by a parabolic law which indicates that oxidation of the sialons is limited by the diffusion processes. No marked changes were detected in the lattice spacing of the sialon after oxidation.Translated from Poroshkovaya Metallurgiya, No. 6(306), pp. 69–73, June, 1988.     

Synthesis and Crystal Structure of Heteronuclear Complex of Copper and Ytrium with Glycine

ＳｙｎｔｈｅｓｉｓａｎｄＣｒｙｓｔａｌＳｔｒｕｃｔｕｒｅｏｆＨｅｔｅｒｏｎｕｃｌｅａｒＣｏｍｐｌｅｘｏｆＣｏｐｐｅｒａｎｄＹｔｒｉｕｍｗｉｔｈＧｌｙｃｉｎｅＷａｎｇＲｕｉｙａｏ（王瑞瑶），ＧａｏＦｅｎｇ（高峰），ＪｉｎＴｉａｎｚｈｕ（金天柱）（...     

Effect of Fluorides and Cerium Dioxide Additives onEP and Antiwear Performance of Grease

ＥｆｆｅｃｔｏｆＦｌｕｏｒｉｄｅｓａｎｄＣｅｒｉｕｍＤｉｏｘｉｄｅＡｄｄｉｔｉｖｅｓｏｎＥＰａｎｄＡｎｔｉｗｅａｒＰｅｒｆｏｒｍａｎｃｅｏｆＧｒｅａｓｅＬｉａｎＹａｆｅｎｇ（连亚锋）（ＧｕａｎｇｚｈｏｕＭａｃｈｉｎｅＴｏｏｌＲｅｓｅａｒｃｈＩｎｓｔｉ...     

Internal Friction and Profile of Property and Structure of PD3 and PD3RE Rail Steels

~~Internal Friction and Profile of Property and Structure of PD_3 and PD_3RE Rail Steels     

Effects of RE and N on Properties of Corrosion Resistance and Oxidation Resistance of Gray Cast Iron

ＩｔｉｓｗｅｌｋｎｏｗｎｔｈａｔｔｈｅｍｅｃｈａｎｉｃａｌｐｒｏｐｅｒｔｉｅｓｏｆｇｒａｙｃａｓｔｉｒｏｎｃａｎｂｅｉｍｐｒｏｖｅｄｂｙａｄｄｉｎｇｓｕｉｔａｂｌｅａｍｏｕｎｔｏｆＲＥａｎｄＮ．Ｔｏｈｉｇｈｃａｒｂｏｎｅｑｕｉｖａｌｅｎｔ（ＣＥ）ｇｒ...     

Effect of Scandium and Zirconium on Mechanical and Exfoliation Corrosion Properties of Al-Mg-Mn Alloys

To quest for the best combination of mechanical properties and exfoliation corrosion resisting property of Al-Mg-Mn base alloys, and to seek after the effect of Sc and Zr on mechanical and exfoliation corrosion properties of Al-Mg-Mn alloys, comparative research technique was used, the mechanical properties of Al-Mg-Mn alloys with and without minor Sc and Zr treated by different annealing were measured, the degrees of exfoliation corrosion for these alloys through accelerated exfoliation corrosion test were evaluated, and polarization curves of these alloys were measured, too. The micro-morphologies of corrosion specimens were observed by SEM and the corrosion product was analyzed using EDS. Optical microscope and TEM were used, the relationship between their microstruc-tures and mechanical properties, exfoliation corrosion resisting property was investigated, and the results show that the addition of minor Sc and Zr can enhance the strength greatly and also improve the combination of strength and plasticity. Moreover, the addition of minor Sc, Zr does not cause appreciable decrease of exfoliation corrosion resisting property, the Al-Mg-Mn-Sc-Zr alloy annealed at 350 ℃ for 1 h has excellent combination of mechanical properties and exfoliation corrosion resisting property, the satisfied combination of mechanical properties nad exfoliation corrosion resisting property can be obtained by means of adding minor Sc and Zr, decreasing the content of Mn, and adopting reasonable annealing practice.     

Distribution and Accumulation of Neodymium and Its Effect on Secretion of Progesterone in Mice

Rareearthelementshavebeenincreasinglyusedinagriculture ,animalhusbandryandfisheryinChinasinceREcanpromotegrowthofcropsandani mals[1,2 ] .However ,studieshaveshownthatoverex posureofREmayhavenegativeortoxiceffectsonor ganisms ,forexample ,inhibitingenzymeactivityandinterferinginmetabolism ,havinghighaffinitytoCa2 bindingsitesanddown regulatingabsorptionandfunc tionofCa2 ,blockingbloodclotting ,inducingpatho histologicallesionsofliver ,aswellasaffectinggo nadalfunction[3～6 ] .Furthermore ,…     

Comparison of the fatigue and fracture of α+β and β titanium alloys

The present study compares the fatigue and fracture properties of the high-strength β titanium alloy β-Cez with the conventional α+β titanium alloy Ti-6Al-4V, because of increasing interest in replacing α+β titanium alloys with β titanium alloys for highly stressed airframe and jet engine components. This comparison study includes the Ti-6Al-4V alloy in an α+ β-processed condition (for a typical turbine blade application) and the β-Cez alloy in two distinctly different α+β-processed and β-processed conditions (optimized for a combination of superior strength, ductility, and fracture toughness). The comparison principally showed a much lower yield stress for Ti-6Al-4V (915 MPa) than for both β-Cez conditions (1200 MPa). The Ti-6Al-4V material also showed the significantly lower high-cycle fatigue strength (resistance against crack initiation) of 375 MPa (R=−1) as compared to the β-Cez alloy (∼600 MPa, R=−1). Particularly in the presence of large cracks (>5 mm), the fatigue crack growth resistance and fracture toughness of the Ti-6Al-4V material is superior when compared to both β-Cez conditions. However, for small crack sizes, the conditions of both the alloys under study show equivalent resistance against fatigue crack growth. For the β-Cez material, where microstructures were optimized for high fracture toughness (conventional large crack sizes) by thermomechanical processing, maximum K _Ic-values of 68 MPa√m of the β-processed β-Cez condition (tested in the longitudinal direction) decreased by ∼50 pct in the presence of small cracks (1 mm). A similar decrease in fracture toughness was obtained by loading the β-processed β-Cez condition perpendicular to the flat surfaces of the pancake-shaped β grain structure (tested in the short transverse direction). These results were discussed in terms of the effectiveness of the crack front geometry in hindering crack propagation. Further, the results of this study were considered for alloy selection and optimized microstructures for fatigue and fracture critical applications. Finally, the advantage of the α+β-processed β-Cez condition in highly stressed engineering components is pointed out because of its overall superior combination of fatigue crack initiation and propagation resistance (especially against small fatigue cracks).     

Studies on Solvent System of Cesium Chloride and Lanthanum Chloride and Synthesization of Four Types of New Compounds

ＳｔｕｄｉｅｓｏｎＳｏｌｖｅｎｔＳｙｓｔｅｍｏｆＣｅｓｉｕｍＣｈｌｏｒｉｄｅａｎｄＬａｎｔｈａｎｕｍＣｈｌｏｒｉｄｅａｎｄＳｙｎｔｈｅｓｉｚａｔｉｏｎｏｆＦｏｕｒＴｙｐｅｓｏｆＮｅｗＣｏｍｐｏｕｎｄｓＬｉＹａｈｏｎｇ（李亚红），ＲａｎＸｉｎｑｕａｎ...     

Interaction of Complex of Europium and Hbbimp with DNA

TheartificialnucleasesforcleavingDNAhavebecomemoreimportant.Theenzymesystemmimicing theenzymaticsiteisthedicopperenzymehemocyanin thathasattractedmoreinterest[1～5].Somestudiesre portedthatmanynaturalenzymeswiththegoodactivi tiesalwayscontaintwoorthreeint…     

Synthesis and Characterization of Rare Earth Complexes of Ferrocenylcarbonylhydrazine

Ｔｈｅｍｅｔａｌｃｏｍｐｌｅｘｅｓｏｆｈｙｄｒａｚｉｄｅｓｈａｖｅａｔｔｒａｃｔｅｄｃｏｎｓｉｄｅｒａｂｌｅｉｎｔｅｒｅｓｔｏｗｉｎｇｔｏｔｈｅｉｒａｎｔｉｆｕｎｇａｌａｎｄａｎｔｉｂａｃｔｅｒｉａｌａｃｔｉｖｉｔｉｅｓ[1 ,2 ] .Ｔｈｅｙｃａｎａｌｓｏｂｅｕｓｅｄａｓａｎａｌｙｔｉｃａｌｒｅａｇｅｎｔｓ[3 ]ａｎｄｅｘｔｒａｃｔｉｎｇａｇｅｎｔｓｆｏｒｍｅｔａｌｓａｌｔｓ[4 ] .Ｍａｎｙｃｏｍｐｌｅｘｅｓｏｆｈｙｄｒａｚｉｄｅｓｈａｖｅｂｅｅｎｓｙｎｔｈｅｓｉｚｅｄａｎｄｃｈａｒａｃｔｅｒｉｚｅｄ[5]…     

Oxidation and Antioxidation of Nanocrystalline Powders of Nd-Fe-B

ＯｘｉｄａｔｉｏｎａｎｄＡｎｔｉｏｘｉｄａｔｉｏｎｏｆＮａｎｏｃｒｙｓｔａｌｉｎｅＰｏｗｄｅｒｓｏｆＮｄＦｅＢＷｅｎＤｉｊｉａｎｇ（闻荻江）（ＳｃｈｏｌｏｆＣｈｅｍｉｓｔｒｙａｎｄＣｈｅｍｉｃａｌＥｎｇｉｎｅｒｉｎｇ，ＳｕｚｈｏｕＵｎｉｖｅｒｓｉ...     

Stiffness of ramming mixes and refractory mortar joints – effects of temperature and installation practice

In refractory linings, the behaviour of ramming and mortar joints is essential for the performance of the whole structure. The compressive stiffness of commercially available ramming mixes and mortars is discussed in this paper. Effects of temperature, density and the joint thickness are analysed. The data are obtained using uni-axial tests with lateral constraints, maximally representative for the service conditions. The results indicate that above 700°C for the ramming and in the range 300–1000°C for the mortar, the joints are to develop stiffness of the same order of magnitude as the surrounding refractories. Viscosity effects are expected below 50°C and above 1000°C for ramming and mortar, respectively. The deviation from the specified density and the joint thickness is to affect the joint stiffness in the whole service temperature range.     

Thermodynamic Calculations of Composition of Carbide and Nitride Precipitates and Precipitation Order in Multi-Microalloyed Steels

ＴｈｅｒｍｏｄｙｎａｍｉｃＣａｌｃｕｌａｔｉｏｎｓｏｆＣｏｍｐｏｓｉｔｉｏｎｏｆＣａｒｂｉｄｅａｎｄＮｉｔｒｉｄｅＰｒｅｃｉｐｉｔａｔｅｓａｎｄＰｒｅｃｉｐｉｔａｔｉｏｎＯｒｄｅｒｉｎＭｕｌｔｉ┐ＭｉｃｒｏａｌｏｙｅｄＳｔｅｅｌｓＱｕＪｉｎｂｏ，Ｗａ...     

Effects of Lanthanum Ion and Its Complexes on Permeability of Pollen Plasmalemma and Pollen Germination

Effects of Lanthanum Ion and Its Complexes on Permeability of Pollen Plasmalemma and Pollen Germination     

China''''s imports and exports of nickel and cobalt by category

~~China's imports and exports of nickel and cobalt by category~~