scholarly journals Effect of Extrusion Ratio & Extrusion Temperature on Mechanical Properties of Hot Extruded Hybrid Composites of Al6061/Sic/Graphite

In this work hot extrusion of hybrid composites of Al6061/SiC/Gr was carried out at ratios of 2:1,3:1&4:1 & temperatures of 4500 ,5000 ,&5500 c at various compositions of 0,2,4,6 &8 % of SiC and fixed amount of graphite i.e 2% using 200 tonn capacity press at a speed of 1mm/sec to investigate mechanical properties like tensile, compression & BHN and after solutionising and aging .It was found that at ratio 3:1 and temperature 5000 c all the above three properties were found to be improved compared to extrusion .

2011 ◽  
Vol 704-705 ◽  
pp. 892-896
Author(s):  
Bao Hong Zhang ◽  
Zhi Min Zhang

In order to study the effect of plastic deformation on microstructure and mechanical properties of as-cast AZ91 magnesium alloy, experiments of hot direct extrusion were performed at different extrusion temperatures and different extrusion ratios. The microstructure and mechanical properties of extruded billets and extrudate were measured. Experimental results show that the grain size of as-cast AZ91 magnesium alloy can be dramatically refined by extrusion. Hot extrusion can obviously improve the mechanical properties of as-cast AZ91 magnesium Alloy, comparing with the pre-extruded billet, the tensile strength, yield strength and elongation of extrudate can be improved by at least 69%, 117% and 150% respectively. As the extrusion temperature increases, the tensile strength and yield strength of extrudate will increase. As the extrusion ratio increases, the tensile strength and yield strength of extrudate will increase at first and then fall. At the time of extrusion temperature of 420°C and extrusion ratio of 45, the highest tensile strength of 381Mpa and yield strength of 303MPa can be achieved for the extrudate.


JOM ◽  
2013 ◽  
Vol 65 (5) ◽  
pp. 593-598 ◽  
Author(s):  
Y. C. Feng ◽  
G. J. Cao ◽  
G. H. Fan ◽  
L. P. Wang ◽  
L. Geng ◽  
...  

2011 ◽  
Vol 291-294 ◽  
pp. 1082-1086
Author(s):  
Yao Jin Wu ◽  
Zhi Ming Zhang ◽  
Bao Cheng Li ◽  
Bao Hong Zhang ◽  
Jian Min Yu ◽  
...  

In the present research, the influences of different extrusion ratios (15, 30, 45, 60, and 75) and extrusion temperature (300°C, 330°C, 360°C, 390°C, 420°C) on the mechanical properties and microstructure changes of AZ80 magnesium alloy have been investigated through tensile test and via ZEISS digital metallographic microscope observation. Research indicates that the alloy’s plasticity gradually decreases as the temperature increases, and that the alloy’s tensile strength varies with the extrusion ratio. At 330°C, the alloy’s particle grain is small and a small amount of black hard and brittle second-phase β (Mg17Al12) are precipitated uniformly along the grain boundary causing the gradual increase of the alloy’s tensile strength. When the extrusion temperature is up to 390°C, the grain size increases significantly, but the second phase precipitation along grain boundaries transforms into continuous and uniform-distribution precipitation within the grain. In this case, when the extrusion ratio is 60, the alloy’s tensile strength reaches its peak 390 Mpa. As the extrusion temperature increases, inhomogeneous precipitation of the second-phase along grain boundaries increases, causing the decrease of the alloy’s strength. At the same temperature, both the tensile strength and plasticity increases firstly and then decreases as extrusion ratio increases. With the gradual increase of the refinement grain, the dispersed precipitates increase and the alloy’s tensile strength and plasticity reach their peaks when the extrusion temperature is 390°C. As the grain grows, the second phase becomes inhomogeneous distribution, and the alloy’s strength and plasticity gradually decrease.


2010 ◽  
Vol 139-141 ◽  
pp. 180-184
Author(s):  
Yong Xue ◽  
Zhi Min Zhang ◽  
Li Hui Lang

In the present research, the influences of different extrusion ratios (15, 30, 45, 60, and 75) and extrusion temperatures (300°C, 330°C, 360°C, 390°C, 420°C) on the mechanical properties and microstructure of homogenized AZ80 alloy have been investigated through the tensile tests and via metallographic microscope observation. The results show that the alloy’s grain is small and small amounts of black hard and brittle second-phase β (Mg17Al12) are precipitated uniformly along the grain boundary causing the gradual increase of the alloy’s tensile strength at 330°C. When the extrusion temperature is up to 390°C, the grain size increases significantly, but the second phase precipitation along grain boundaries transforms into continuous and uniform-distribution precipitation within the grain. In this case, when the extrusion ratio is 60, the alloy’s tensile strength reaches its peak 390Mpa. As the extrusion temperature increases, inhomogeneous precipitation of the second-phase along grain boundaries increases, causing the decrease of the alloy’s strength. At the same temperature, the tensile strength increases firstly and then decreases as extrusion ratio increases. With the gradual increase of the refinement grain, the dispersed precipitates increase and the alloy’s tensile strength and plasticity reach their peaks when the extrusion temperature is 390°C. As the grain grows, the second phase becomes inhomogeneous distribution, and the alloy’s strength and plasticity gradually decrease.


2009 ◽  
Vol 610-613 ◽  
pp. 796-800 ◽  
Author(s):  
Jian Peng ◽  
Cheng Meng Song ◽  
Ya Zhong Zhao ◽  
Fu Sheng Pan

The mechanical properties and microstructure of the as-extruded ZM21 magnesium alloy and its modified alloy ZME210 with addition of 0.35wt% cerium were investigated with different extrusion ratios from 14 to 182 by using mechanical property test, microscopic structure quantitative analysis, SEM observation and energy spectrum analysis. The results showed that both ZM21 and ZME210 had an extrusion ratio limit for grain refining, and the grains were found to be finer with higher extrusion ratio when the ratio was not higher than the limit value. The extrusion ratio limit for the best effect for grain refining of ZME210 is lower than that of ZM21. It was found that the Ce can refine the grains effectively after hot extrusion with different extrusion ratios. The effects of Ce on the microstructure and mechanical properties were analyzed.


2006 ◽  
Vol 503-504 ◽  
pp. 775-780 ◽  
Author(s):  
Takeshi Yamaguchi ◽  
Tadayoshi Tsukeda ◽  
Ken Saito ◽  
Yoshihito Kawamura

In order to make the effect of processing clear, AM50A magnesium casting alloys were extruded at various extrusion conditions such as extrusion temperature and extrusion ratio. The mechanical properties of AM50A alloy increased with decreasing extrusion temperature. Tensile yield strength and tensile strength of extruded AM50A alloy were 389MPa and 420MPa respectively when the extrusion temperature was 348K. The microstructure of the extruded magnesium alloy showed large grains stretched to the extrusion direction and fine recrystallized grains. Decreased extrusion temperature resulted in improved strength and decreased elongation with increasing of the degree of work hardens and extrusion force. When the extrusion ratio is high, improvement of strength is prevented by rycrystallization and it was observed as crystal orientation by XRD. The elongation of the extrusion increased with the recrystallization of grains. Every magnesium alloy extruded at low temperature has high strength.


2006 ◽  
Vol 324-325 ◽  
pp. 499-502
Author(s):  
Ze Sheng Ji ◽  
Mao Liang Hu ◽  
Xiao Yu Chen

AZ91D magnesium alloy is prepared by hot extrusion of recycled machined chips and its fractures and mechanical properties are investigated at various extrusion conditions. Cold-press is employed to prepare extrusion billets of AZ91D magnesium alloy chips, and then the billets are hot extruded at 573K-723K with an extrusion ratio of 11:1. The results show that tensile strength and elongation of the extrusion magnesium alloy with the extrusion temperature of 673K and the extrusion rate of 0.08mm/s can reach 380MPa and 6%, respectively. Fracture surface presents a mix mechanism of dimple-like fracture and gliding fracture. Due to grain refinement by cold-press and hot extrusion, mechanical properties of extruded rods are much higher than those of as-cast AZ91D magnesium alloy. Also, much lower energy consumption is necessary for this recycling compared to the conventional casting process. Solid state recycling is an efficient method for magnesium alloy chips recycling.


2013 ◽  
Vol 762 ◽  
pp. 520-525
Author(s):  
Qiang Lin ◽  
Zu Yan Liu ◽  
Xin Yan Su

In this paper, based on the determination of the stress-strain relationship of sintered W-40wt.%Cu by upsetting tests, the hot extrusion process of the materials covered with a steel cup has been simulated by DEFORM. The effect of the thickness of steel cup, extrusion temperature and extrusion ratio on the extrusion process has been studied, so that a group of optimal parameters could be obtained which is useful to the experiment of powder compact by extrusion with cups.


Sign in / Sign up

Export Citation Format

Share Document