scholarly journals Microstructural evolution and Mechanical Properties of a Newly Developed Ti2AlNb-based alloy

2020 ◽  
Vol 321 ◽  
pp. 11064
Author(s):  
Yongsheng HE ◽  
Wenzhong LUO ◽  
Yujun DU ◽  
Ming WU ◽  
Kaixuan Wang ◽  
...  
Keyword(s):  
Tensile Strength ◽  
High Temperature ◽  
Room Temperature ◽  
Phase Region ◽  
High Plasticity ◽  
Phase Zone ◽  
Creep Properties ◽  
Three Phase ◽  
High Temperature Tensile ◽  
High Temperature Tensile Properties

The effects of the microstructure on the tensile and creep properties of the alloy at room temperature and high temperature were investigated by controlling the microstructures of the alloy by different hot working processes. It is found that the lath microstructure obtained by forging in B2 single phase zone has high tensile strength. The tensile strength is 1188 MPa at room temperature and 950 MPa at high temperature. The equiaxed structure obtained by forging in O+B2 phase region has the characteristics of high plasticity, creep resistance and low tensile strength. The elongation at room temperature is 9.0%, and the elongation at high temperature is 36%. The ambient temperature, high temperature tensile properties of the dual microstructure obtained by forging in the three-phase zone of α2+O+B2 are between the lath and the equiaxed microstructure.

Microstructure and High Temperature Properties of 85% Al2O3-15% SiO2 Fibers

1994 ◽  
Vol 350 ◽  
Author(s):  
D. M. Wilson ◽  
S. L. Lieder ◽  
D. C. Lueneburg
Keyword(s):  
Tensile Strength ◽  
High Temperature ◽  
Sol Gel ◽  
Two Phase ◽  
Single Filament ◽  
Polycrystalline Alumina ◽  
Creep Properties ◽  
High Temperature Properties ◽  
Alumina Fibers ◽  
High Temperature Tensile

AbstractA new sol/gel fiber which exhibits exceptional high temperature properties was recently developed at 3M. This fiber has the composition 85% Al2O3-15% SiO2 (85A-15S). High temperature tensile strength and creep properties were measured in the temperature range 1000°C – 1300°C. The creep rate for the 85A-15S fibers was three orders of magnitude less than single phase polycrystalline alumina fibers such as Nextel 610, and 90% of room tensile strength was retained at 1250°C. These exceptional high temperature properties were attributed to a unique, two-phase microstructure consisting of globular and elongated grains of a-Al2O3 and mullite (3Al2O3-2SiO2). The room temperature single filament strength of the 85% Al2O3-15% SiO2 fibers was 2130 MPa, and the elastic modulus was 260 GPa.

The Effects of Nb and Cr Addition on Mechanical and Chemical Properties of Cold-Rolled Ni3(Si,Ti) Intermetallic Foils

2007 ◽  
Vol 561-565 ◽  
pp. 411-414 ◽  
Author(s):  
Yasuyuki Kaneno ◽  
Takayuki Takasugi
Keyword(s):  
Tensile Strength ◽  
High Temperature ◽  
Room Temperature ◽  
Chemical Properties ◽  
Solid Solution Phase ◽  
Two Phase ◽  
Thermomechanical Process ◽  
Thin Foils ◽  
Cold Rolled ◽  
High Temperature Tensile

Nb and/or Cr added Ni3(Si,Ti) as well as unalloyed Ni3(Si,Ti) intermetallic thin foils (i.e., Ni3(Si,Ti), Ni3(Si,Ti)+Nb, Ni3(Si,Ti)+Cr and Ni3(Si,Ti)+Nb,Cr) were fabricated from arc-melted polycrystalline ingots by thermomechanical process and subsequent heavy cold-rolling. Tensile property at room temperature as well as at high temperature and oxidization behavior of the cold-rolled foils with a thickness of ~200μm were investigated. The Ni3(Si,Ti) and Ni3(Si,Ti)+Nb alloys showed a single-phase microstructure consisting of L12 phase, while the Ni3(Si,Ti)+Cr and Ni3(Si,Ti)+Nb,Cr alloys exhibited a two-phase microstructure with A1 (fcc) Ni solid solution phase within the L12 grains. All the cold-rolled foils showed high tensile strength (over 2GPa) at room temperature although no plastic elongation was observed. The addition of Nb and/or Cr slightly enhanced the room-temperature tensile strength of the Ni3(Si,Ti) alloy. On the other hand, the addition of Nb and/or Cr prominently enhanced high-temperature tensile strength as well as oxidization resistance, while the addition of Cr improved high-temperature elongation.

Role of Ti/Al Ratio of Ti-Al-X (X=Cr, Nb, Ta and W) Intermetallics on High Temperature Tensile Properties

2014 ◽  
Vol 783-786 ◽  
pp. 1136-1141
Author(s):  
Keizo Hashimoto
Keyword(s):  
Tensile Strength ◽  
High Temperature ◽  
Tensile Properties ◽  
First Generation ◽  
Elevated Temperatures ◽  
Atomic Ratio ◽  
High Temperature Strength ◽  
The Third ◽  
High Temperature Tensile ◽  
High Temperature Tensile Properties

The mechanical properties of g-TiAl at elevated temperatures have been investigated extensively over the last 30 years. Designed alloys have been proposed from the first generation alloy (Ti-48Al-2Cr-2Nb) to the second, the third and the fourth generations. However, a decisive chemical composition of g-TiAl has not been agreed among researchers yet. The main reasons for this situation are difficulties in compositional control of Ti-Al-X-Y. In this paper, the high temperature tensile properties of g-TiAl alloy with lots of different composition have been examined from the room temperature to 1200C and the tensile strength data of those specimens have been summarized. It is clear that Ti/Al atomic ratio plays an important role on the behaviors of the high temperature strength since the Ti/Al atomic ratio is strongly related to the phase stabilities between g and a2phases in the binary Ti-Al phase diagram. A very narrow confine of a/a2atomic ratio exists in the specimens having the comparatively high tensile strength at the elevated temperatures. Moreover, additions of the third elements such as Cr, Nb, Ta and W to g-TiAl contribute on the increase of the tensile strength and the shift of the phase stability among a2, b and g phases. In order to utilize g-TiAl alloys in the various machine components at high temperatures, the severe process controls of melting, casting, thermo-mechanical treatments and heat treatments are indispensable.

scholarly journals Microstructure and High Temperature Tensile Properties of Mg–10Gd–5Y–0.5Zr Alloy after Thermo-Mechanical Processing

Metals ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 980 ◽  
Author(s):  
Guohua Wu ◽  
H. Jafari Nodooshan ◽  
Xiaoqin Zeng ◽  
Wencai Liu ◽  
Dejiang Li ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
High Temperature ◽  
Tensile Properties ◽  
Test Temperature ◽  
Mechanical Processing ◽  
Twin Boundaries ◽  
High Temperature Mechanical Properties ◽  
High Temperature Tensile ◽  
High Temperature Tensile Properties

The microstructure, high-temperature tensile properties and fracture behavior of the Mg-10Gd-5Y-0.5Zr alloy after thermo-mechanical processing (pre-tension between solution and aging treatment) were investigated. The pre-deformed alloy shows the accelerated aging kinetics compared to the un-deformed alloy. Microstructure of pre-deformed samples showed not only the homogeneous nucleation of the precipitate but also heterogeneous nucleation of precipitates on the dislocation and twin boundaries. Tensile results show that the pre-deformation enhanced the strength of the alloy, while it deteriorates the ductility of the alloy. The ultimate tensile strength (UTS) of the T6 treated un-deformed and pre-deformed alloy at room temperature are 331 MPa and 366 MPa, respectively. Tensile strength of the T6 treated alloy in both un-deformed and deformed conditions was enhanced by raising the test temperature and then reduced by further raising the test temperature. The higher strength of the pre-deformed alloy could be related to the higher density of the precipitates, which grow on the twin boundaries and can hinder the dislocation movement and strengthen the alloy. The results shows that thermo-mechanical processing can significantly improve the room- and high-temperature mechanical properties and enhance the formation of precipitates in Mg-10Gd-5Y-0.5Zr alloy, which can lead to wider application of the alloy in industries such as aerospace or powertrains that need better room- and high-temperature mechanical properties.

Sign in / Sign up

Export Citation Format

Share Document