Peritectic Reaction of High Nb and W Pentatomic TiAl-Based Alloy

2011 ◽  
Vol 335-336 ◽  
pp. 831-835
Author(s):  
Hong Liang Sun ◽  
Cai Sun ◽  
Ze Wen Huang ◽  
De Gui Zhu

The effect of different aluminum content on peritectic reaction and mechanical properties of pentatomic TiAl-based alloy was investigated. The results indicate that the grain size gradually increase with increasing content of aluminum and addition 45.7% aluminum in TiAl-based alloy results in that the peritectic reaction can increase grain size greatly, respectively. The content of aluminum can increase the room temperature strength, high temperature strength but peritectic reaction can effectively reduce tensile strength. Aluminum content has a little effect on the ductility. The stress rupture life has positive correlation relationship with the content of aluminum.

2013 ◽  
Vol 275-277 ◽  
pp. 1884-1889
Author(s):  
Hong Liang Sun ◽  
Ze Wen Huang ◽  
De Gui Zhu

The effect of different tungsten addition on microstructure and mechanical property of TiAl-based alloy was investigated. The results indicate that the size and amount of β (B2) phase and equiaxed γ phase gradually increase with increasing content of tungsten. The grain size and lamellar spacing obey a parabolic law. The tungsten addition can increase the room temperature strength, high temperature strength but have a little effect on the ductility. The creep rupture life has inverse correlation relationship with the content of tungsten.


2016 ◽  
Vol 849 ◽  
pp. 549-556
Author(s):  
Pin Pin Hu ◽  
Qi Dong Gai ◽  
Qing Li ◽  
Xin Tang

The effect of Microcast-X fine grain casting on the microstructure and mechnical property K492M alloy at 760°C of was investigated. The results indicated that Microcast-X fine grain casting decreased grain size and dendrite space of γ′ phase and γ/γ′ eutectic. In addition, the element segregation decreased significantly compared to conventional casting technique. Also, the size and distribution of MC carbide were improved. By Microcast-X fine grain casting, the tensile strength increased from 934MPa of conventional casting alloy to 1089MPa and the elongation increased from 1.9% to 5.7%. In addition, the stress-rupture life increased from 28.8h of conventional casting alloy to 72.5h. And the fracture mechanism for the alloys by Microcast-X fine grain casting is trans-granular fracture toughness.


2016 ◽  
Vol 849 ◽  
pp. 570-579
Author(s):  
Qiang Huang ◽  
Jin Xia Song ◽  
Qing Li ◽  
Wei Peng Ren ◽  
Xin Guang Guan ◽  
...  

The microstructures and mechanical properties of superalloy K465 under different heat treatment, including as as-cast, solution treatment and aging, were investigated. The results showed that γ' precipitates in as-cast condition exhibited two kinds of morphologies of fine regular cuboidal shape at dendritic arm and coarse irregular form in interdendritic region. MC carbides decomposed into M6C carbides partly after 1210°C/4h solution treatment. The high temperature stress-rupture life can be improved obviously with the increasing cooling rate. When cooling rate was lower than 70°C/min, the room temperature tensile elongation increased with cooling rate increasing. When cooling rate was higher than 90°C/min the room temperature tensile elongation decreased with cooling rate increasing. The proper cooling rate of 70oC/min~90oC/min is advantageous for the achievement of excellent comprehensive properties. When aging treatments continued the regularization of γ' resulted in the improvement of stress-rupture life and the reduction of tensile elongation. The mechanical property gap between the solution treatment and aging can be decreased with increasing cooling rate.


10.30544/72 ◽  
2015 ◽  
Vol 21 (4) ◽  
pp. 259-268 ◽  
Author(s):  
Seyed Ali Hosseini ◽  
Seyed Mehdi Abbasi ◽  
Karim Zanganeh Madar

The effects of boron and zirconium on the microstructure, hardness and stressrupture life of the nickel-based superalloy ATI 718Plus were investigated in this study. Four alloys with different percentages of boron (0.005-0.01 wt.%) and zirconium (0-0.1 wt%) were cast through a vacuum induction melting furnace and then were rolled. The microstructural studies indicated an increased percentage of δ phase, carbide precipitates and twins in the presence of zirconium. The percentage of carbide (boron carbide) precipitates was increased and the solidification range of the alloy was decreased in the presence of boron in the composition. Furthermore, the results obtained from the hardness and stress-rupture tests showed the significant role of both elements in increasing hardness and improved rupture life of the alloy. The maximum rupture life was observed in the alloy which contained the highest percentages of boron and zirconium in its composition. This can be attributed mainly to the increased percentage of δ phase on grain boundaries and their enhanced high-temperature strength.


2015 ◽  
Vol 65 ◽  
pp. 840-846 ◽  
Author(s):  
Yulai Xu ◽  
Qinghuan Liu ◽  
Feng Wang ◽  
Jun Li ◽  
Xueshan Xiao ◽  
...  

Author(s):  
D. E. Fornwalt ◽  
A. R. Geary ◽  
B. H. Kear

A systematic study has been made of the effects of various heat treatments on the microstructures of several experimental high volume fraction γ’ precipitation hardened nickel-base alloys, after doping with ∼2 w/o Hf so as to improve the stress rupture life and ductility. The most significant microstructural chan§e brought about by prolonged aging at temperatures in the range 1600°-1900°F was the decoration of grain boundaries with precipitate particles.Precipitation along the grain boundaries was first detected by optical microscopy, but it was necessary to use the scanning electron microscope to reveal the details of the precipitate morphology. Figure 1(a) shows the grain boundary precipitates in relief, after partial dissolution of the surrounding γ + γ’ matrix.


2016 ◽  
Vol 849 ◽  
pp. 513-519
Author(s):  
Qing Quan Zhang ◽  
Ming Yang Li ◽  
Ran Wei ◽  
Hui Yun Wu ◽  
Zhen Rui Li

Ni-Cr-Co type Nickel-based super alloy Inconel 740H was studied. The effect of Nb, Al and Ti on the equilibrium of this alloy was analyzed by JMatPro software. The amount of Ti and Nb should be controlled by 1.50wt.%, and meanwhile, Al should be 1.0-2.0wt.%. If Mo and W were added the amount of Mo should be in the range of 1.0-2.0wt. %, and W should be about 1.0wt.%. Based on these results, three types of new alloys were designed, which contain Ni-Cr-Co-Mo type (1#), Ni-Cr-Co-W type (2#) and Ni-Cr-Co-Mo-W type (3#). Compared with the Ni-Cr-Co type Inconel 740H alloy, the room temperature strength, high temperature strength and high temperature durable performance of the three new alloys improved, which can provide the evidence and reference to optimize the chemical composition of Inconel 740H alloy, i.e., adding 1.50wt.% Mo and 1.0wt.% W individually or together.


2017 ◽  
Vol 898 ◽  
pp. 422-429 ◽  
Author(s):  
Wei Guo Zhang ◽  
Zhi Jie Liu ◽  
Song Ke Feng ◽  
Fu Zeng Yang ◽  
Lin Liu

The stress rupture life of DZ125 nickel-based superalloy that was prepared by directional solidification process under the temperature gradient of 500 K/cm has been studied at 900°C and 235MPa. The results showed that with the increase of directional solidification rate from 50 μm/s to 800 μm/s, the primary dendrite arm spacing reduced from 94 μm to 35.8 μm and γ' precipitates reduced and more uniformed in size. The high temperature stress rupture life of as-cast sample increased firstly and then decreased and reached its maximum at the solidification rate of 500 μm/s. The dislocation configuration of sample with refine dendritic structure after stress rupture was investigated and discovered that the dislocations in different parts of sample had different morphology and density, which indicated that the deformation of as-cast samples were uneven during high temperature stress rupture. A lot of dislocations intertwined around carbides and at the interface of γ/γ', and the dislocation networks were destroyed and the dislocations entered γ' precipitate by the way of cutting.


2022 ◽  
pp. 131656
Author(s):  
Jinbin Chen ◽  
Jingyang Chen ◽  
Qinjia Wang ◽  
Yidong Wu ◽  
Qing Li ◽  
...  

1985 ◽  
Vol 58 ◽  
Author(s):  
A. Brown ◽  
D. Raybould

ABSTRACTIn recent years, interest in high temperature aluminum alloys has increased. However, nearly all the data available is for simple extrusions. This paper looks at the properties of sheet made from a rapidly solidified Al-10Fe-2.5V-2Si alloy. The sheet is made by direct forging followed by hot rolling, this is readily scalable, so allowing the production of large sheet. The room temperature strength and fracture toughness of the sheet are comparable to those of 2014-T6. The high temperature strength, specific stiffness and corrosion resistance are excellent. Recently, improved thermomechanical processing and new alloys have allowed higher strengths and fracture toughness values to be obtained.


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