scholarly journals Evolution of Microstructure, Texture, and Mechanical Properties of As-Extruded ND/ZK60 Composite during Hot Compression Deformation

Metals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1191
Author(s):  
Jinhui Wang ◽  
Shangpeng Li ◽  
Hongbin Ma

The effects of temperature, strain rate, and strain on the microstructure, texture, and mechanical properties of as-extruded nanodiamond reinforced ZK60 composite during hot compression was systematically studied. The results revealed that the precipitating MgZn2 and the nanodiamond (ND) particles distributed in the grain interiors hindered the motion of dislocations. The ND particles act as nucleation points and promote the dynamic recrystallization (DRX) of the composites during the hot compression deformation, the flow stress of ND/ZK60 increases with strain rate increases and temperature decreases. {101¯2} extension twins are nucleated and grown in the coarse grains as the compressive strain increasing. Meanwhile, the fine grains of DRX generate and present first an increasing then a decreasing trend. The result of Schmid factor and kernel average misorientation indicates that high-density dislocation caused by dislocation climbing and cross slip aggregated in composites with increasing strain. Therefore, the work hardening trend of the composite is strengthened.

2021 ◽  
Vol 1035 ◽  
pp. 189-197
Author(s):  
Bao Ying Li ◽  
Bao Hong Zhu

The hot deformation behavior of spray-formed AlSn20Cu alloy during hot compression deformation was studied, and the constitutive equation of AlSn20Cu alloy was established. The samples of spray-formed AlSn20Cu alloy were compressed on Gleeble-3500 thermal simulation test machine. The error of the true stress caused by adiabatic heating effect in the experiment was corrected. The constitutive equation of spray-formed AlSn20Cu alloy could be represented by Zener-Hollomon parameter in a hyperbolic sine function. The results showed that the deformation temperatures and strain rates had a notable effect on the true stress of the alloy. At the identical deformation temperature, the true stress increased with the increase of strain rate. When the strain rate was constant, the stress decreased with the increase of deformation temperature. After hot compression deformation, the tin phase was elongated along the direction perpendicular to the compression axis with short strips and blocks. With the increase of deformation temperature and the decrease of strain rate, Sn phase distribution became more homogeneous.


2016 ◽  
Vol 849 ◽  
pp. 186-195 ◽  
Author(s):  
Jian Min Yu ◽  
Xu Bin Li ◽  
Zhi Min Zhang ◽  
Qiang Wang ◽  
Yao Jin Wu ◽  
...  

The multi-pass hot compression deformation behavior of the cast alloy with the composition of Mg-13Gd-4Y-2Zn-0.6Zr, was investigated, and the four-pass compression tests were conducted at the temperatures ranging from 350°C to 500°C and strain rate 0.01 s-1. The experimental results showed that the alloys incurred different degrees of softening by multipass deformation. The microstructure evolution for the deformed alloy was investigated, the influence of the microstructure on the hardness properties of the alloy discussed. The tests reveal that dynamic recrystallization is not the main softening mechanism for this alloy; rather, kink deformation refines the grains to achieve the observed softening effect. The hardness test curve showed that the hardness increased gradually with an increasing number of deformation passes. The improvement of the main mechanical properties related to the strengthening by the grain refinement. In multipass deformation, the misorientation of the kink belt gradually increased,and refined the grains. On the other hand, the grain size of the eutectic phase at the grain boundary decreased with increase of deformation passes. In addition, the mechanical properties were improved by the distribution dispersion of tiny cuboidal particles and acicular-like phases in the matrix.


2020 ◽  
Vol 167 ◽  
pp. 110486
Author(s):  
Xiao Xu ◽  
Xinwu Ma ◽  
Shubin Yu ◽  
Guoqun Zhao ◽  
Yongxiao Wang ◽  
...  

2011 ◽  
Vol 704-705 ◽  
pp. 223-228 ◽  
Author(s):  
Ronɡ Hua Zhang ◽  
Yon Gan Zhang ◽  
Bao Hong Zhu

The behavior of the flow stress of Al-Fe-V-Si heat-resistant aluminum alloy prepared by spray forming during hot compression deformation was studied. The results show that the true stress-true strain curves of the spray forming Al-Fe-V-Si heat-resistant alloy are characterized by a high true stress occurrence at the early stage of compression, followed by a steady flowing due to recovery and strain softening because of dynamic recrystallization. The flow stress of the alloy decreases with increasing deforming temperature and increases with increasing strain rate. The flow stress of the spray forming Al-Fe-V-Si heat-resistant aluminum alloy during hot compression deforming can be described by constitutive equation in hyperbolic sine function.The deformation activation energy of the alloy during hot deformation by Sellars-Tegart equation is much higher than those of the conventional aluminum alloy. The deformation activation energy decreases with decreasing strain rate at the beginning, then increases with decreasing strain rate. Keywords:Al-Fe-V-Si alloy;heat-resistant aluminum alloy;hot compression deformation;flow stress


2011 ◽  
Vol 213 ◽  
pp. 623-627 ◽  
Author(s):  
Li Zhang ◽  
Ke Xing Song ◽  
Yan Min Zhang ◽  
Qing Wang ◽  
Wei Feng Liu

The Cu-1.1Cr alloys performed in this paper were prepared by thermal deformation + solution treatment + cold deformation + aging treatment + machining. The flow stress behavior of Cu-1.1Cr alloy was investigated by isothermal compression on Gleeble-1500 hot simulator in the temperature range of 400-800°C and strain rate of 0.01-1s-1. The experimental results indicated that the flow stress of Cu-1.1Cr alloy depends on the strain rate and the deformation temperature. The flow stress increased with increasing strain rates and decreased with increasing temperature. The flow stress of Cu-1.1Cr alloy during hot compression deformation could be represented by Zener-Hollomon parameter including the Arrhenius term. The values of n, α and A in the analytical expressions of flow stress are fitted to be n=15.696, α=0.005178MPa-1 and A =1.289×1021s -1, respectively. The hot deformation activation energy is 346.738kJ/mol. The constitutive equation of the Cu-1.1Cr alloy was obtained .


2012 ◽  
Vol 184-185 ◽  
pp. 914-919 ◽  
Author(s):  
Yue Sheng Chai ◽  
Yong Zhe Chen ◽  
Wen Feng Liu ◽  
Gang Sun

Hot compression tests of AZ91D magnesium alloy were performed on Gleeble1500 ranging from 0.001 to 1 s-1 and deformation temperature ranging from 200 to 400°C. The results show that flow stress is dependent on deformation temperature and strain rates.When strain rate is a constant, flow stress decreases with the increasing deformation temperature. Meanwhile, as deformation temperature is a constant, flow stress increases with the increase of strain rate, which can be demonstrated by a Zener-hollomon parameter in the hyperbolic-sine-type equation during hot compression deformation. The hot deformation activation energy is 176.01kJ/mol and the stress exponent is 7.85 during hot compression deformation of AZ91D magnesium alloy.


2011 ◽  
Vol 393-395 ◽  
pp. 312-318
Author(s):  
Qiang Liu ◽  
Xiang Qian Yin ◽  
Bo Duan ◽  
Sheng Ying Shong ◽  
Yao Rong Feng

The hot deformation behavior of TiNiFe shape memory alloy were investigated by isothermal single-pass compression on Gleeble-3500 thermal simulator at the temperature range of 800°C to 1050°C and the strain rate range of 0.01s-1 to 10s-1. The results showed that the true stress-strain curves of TiNiFe shape memory alloy increase with decreasing deformation temperature and increasing strain rate, which indicating that the hot deformations of these conditions are dynamic recrystallization. The hot compression deformation of TiNiFe shape memory alloy can be represented by Arrhenius model. The constitutive equation of TiNiFe shape memory alloy under hot compression deformation is calculated by a linear regression analysis. The activation energy for hot deformation of the experimental steel is 202.54kJ/mol.


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