Entity

Time filter

Source Type


Yang Z.-Q.,Henan University of Science and Technology | Liu Y.,Henan University of Science and Technology | Liu Y.,Henan Collaborative Innovation Center for Non Ferrous Materials General Technology | Tian B.-H.,Henan University of Science and Technology | And 3 more authors.
Cailiao Rechuli Xuebao/Transactions of Materials and Heat Treatment | Year: 2013

The true stress-true strain curves of 20 vol% TiC particle reinforced dispersion-strengthened copper matrix composite were investigated by compression tests at 450-850°C with the strain rate of 0.001-1 s-1 using the Gleeble-1500D simulator. The dynamic recrystallization critical conditions were established according to the work hardening rate approach. The results show that the softening mechanism of the dynamic recrystallization is a feature of flow stress-strain curves of the composites, and the peak stress increases with the decreasing deformation temperature or the increasing strain rate. The inflection point in the lnθ-ε curve appears and minimum value of -∂(lnθ)/∂ε-ε curve is presented when the critical state is attained for this composite. The critical strain and peak critical decrease with the decreasing strain rate and the increasing deformation temperature. There is linear relationship between critical strain and peak strain, i. e. εc/εp=0.5276.


Wang J.-F.,Henan University of Science and Technology | Jia S.-G.,Henan University of Science and Technology | Jia S.-G.,Henan Key Laboratory of Advanced Non Ferrous Materials | Chen S.-H.,Chinalco Luoyang Copper Co. | And 2 more authors.
Cailiao Rechuli Xuebao/Transactions of Materials and Heat Treatment | Year: 2012

Effects of aging temperature and aging time on microstructure and properties of a Cu-Ni-Si-Mg alloy which was produced by continuous casting and rolling process were investigated, and the aging kinetics of the alloy was analyzed. The results show that a better combination of properties is obtained for the alloy aged at 450°C for 2 h, the microhardness and electrical conductivity of the alloy are 242 HV and 35.53%IACS, respectively. Both phase transformation kinetics equation and electrical conductivity equation are derived in terms of the analyses of the electrical conductivity variations during aging, and the transformation kinetics and the electrical conductivity equation curves are obtained. The results obtained by the electrical conductivity equations are in good agreement with the experimental values.


Wang H.G.,Henan University of Science and Technology | Wang H.G.,Henan Key Laboratory of Advanced Non Ferrous Materials | Wang F.,Luoyang Ship Material Research Institute | Song Y.P.,Henan University of Science and Technology | Song Y.P.,Henan Key Laboratory of Advanced Non Ferrous Materials
Applied Mechanics and Materials | Year: 2012

Mechanical properties and microstructures of Ti811 alloys under different heat treatment conditions were studied. The results show that the microstructures of Ti811 alloy consist of α, massive β and grain-boundary β after normal annealing. The intensity and hardness decreased, while the ductility increased. After double annealing, the primary phase α reduced and needle-like secondary α" was formed. The massive β and grain-boundary β changed into intergranular β gradually. The microstructure was relatively uniform. Then the intensity and hardness increased, the ductility decreased when compared to general annealing. The needle-like secondary α" and metastable β would break down into dispersed α and β after solution hardening and aging. The combination properties of alloys would be improved. According to fractography of titanium alloy, the fracture mechanism of the Ti811 alloy was dissociation - brittle intergranular fracture, which was a type of fracture between the intergranular fracture of brittle and cleavage fracture. © (2012) Trans Tech Publications.


Liu Y.,Henan Key Laboratory of Advanced Non Ferrous Materials | Liu X.-L.,Hebi Vocation and Technology College | Zhang J.-D.,Henan Key Laboratory of Advanced Non Ferrous Materials
Jinshu Rechuli/Heat Treatment of Metals | Year: 2011

The mechanical properties and wear resistance of Crl2MoV steel with different deep cryogenic treatments(DCT) were investigated. The results show that the hardness of Crl2MoV steel is improved obviously by the deep cryogenic treatment, the highest increment of microhardness reaches 228 HVO. 2, and the wear resistance is enhanced too. Tempered at 180 °C for 1. 5 h after 3 times deep cryogenic treatment for 1 h, the Crl2MoV steel has the best wear resistance, and its rate of wear loss dropped 37. 1%. Moreover, the retained austenite content decreases obviously to 2. 58% due to the deep cryogenic treatment compared to that of 34. 35% before deep cryogenic treatment. The percent reduction of retained austenite is 92. 5%.


Liu Y.,Henan University of Science and Technology | Liu Y.,Henan Key Laboratory of Advanced Non Ferrous Materials | Zhao R.,Henan University of Science and Technology | Tian B.,Henan University of Science and Technology | And 2 more authors.
Rare Metals | Year: 2011

The hot compression behaviors of W-50%Cu composite were investigated at the strain rate range from 0.01 to 5.00 s -1 and the temperature range from 850 to 1000 °C on Gleeble-1500D hot simulator. The results show that the flow stress during hot compression of W-50%Cu composite is strongly affected by the compression temperature and the strain rate. Moreover, the flow stress decreases with the raising deforming temperature, and increases with the increasing strain rate. The flow stress of the W-50%Cu composite at high temperature can be expressed by Arrhenius model, and the values of structural factor A, stress scale parameter a, stress index n and hot deformation activation Q are 3.18 × 109 s -1, 0.0133 MPa -1, 6.27393 and 239.442 kJ/mol, respectively. © The Nonferrous Metals Society of China and Springer-Verlag Berlin Heidelberg 2011.

Discover hidden collaborations