Superplastic Extrusion of Ultra Fine-Grained 3Y-TZP/Al2O3 Ceramic for Turbine Disk

2007 ◽  
Vol 551-552 ◽  
pp. 501-506 ◽  
Author(s):  
F. Wang ◽  
Kai Feng Zhang ◽  
Wen Bo Han
Keyword(s):  
Mechanical Properties ◽  
Turbine Disk ◽  
Second Phase ◽  
Hot Press ◽  
Sintered Compact ◽  
Fine Grained ◽  
Alumina Composite ◽  
Near Net Shape ◽  
Net Shape Forming ◽  
Undeformed Sample

Superplastic extrusion of axial forcing and radial flowing under different conditions was adopted to form a turbo-rotor, using hot-press sintered compact of zirconia (3Y)-toughened alumina composite that was prepared at 1450 °C for 1 hour with relative density of higher than 96%. Subsequent superplastic extrusion was attempted at temperature of 1500 °C-1650 °C. The results indicate that 3Y-ZrO2 plays an important role as a second-phase pinning agent and inhibits grain growth. The material shows good deformability and potential of near-net-shape forming. Comparing with undeformed sample, extruded sample was observed apparent coarsening in grain size and the remaining mechanical properties after deformation are not improved, irrespective of improved density. The dominating deformation mechanism is grain sliding and rotation accommodated with zirconia coordinated deformation.

Analysis of a Thixo-Lateral Forged Spindle from LTT C45, LTT C38 and LTT 100Cr6 Steel Grades

2014 ◽  
Vol 217-218 ◽  
pp. 347-354 ◽  
Author(s):  
Jokin Lozares ◽  
Zigor Azpilgain ◽  
Iñaki Hurtado ◽  
Iñigo Loizaga
Keyword(s):  
Mechanical Properties ◽  
Current Trend ◽  
Research Work ◽  
Raw Material ◽  
Key Factor ◽  
Steel Grades ◽  
Near Net Shape ◽  
Net Shape Forming ◽  
Near Net Shaping ◽  
Net Shaping

Due to the current trend in prices of raw material and their sources, near net shaping of mechanical components will become a key factor for the companies to get the desired competitiveness. Semisolid metal (SSM) forming is one of those near net shape forming techniques revealing a high potential to reduce material as well as energy consumption compared to conventional process technologies. Thus, the aim of this research work is to demonstrate the above by manufacturing a steel commercial automotive spindle by thixo-lateral forming from three different steel grades. The starting material, the microstructure and mechanical properties are analysed along the article. Material savings of 20% have been reported together with a substantial decrease of the forming forces. In addition, great mechanical properties have been achieved which brings the process closer to the desired final industrial application.

Effect of Porosity on Mechanical Properties of Ti-5Al-2.5Sn ELI Alloy from Atomized Powder

2015 ◽  
Vol 817 ◽  
pp. 587-592 ◽  
Author(s):  
Lei Xu ◽  
Rui Peng Guo ◽  
Rui Yang
Keyword(s):  
Mechanical Properties ◽  
Hot Isostatic Pressing ◽  
Cryogenic Temperatures ◽  
Significant Difference ◽  
Complex Shapes ◽  
Near Net Shape ◽  
Net Shape Forming ◽  
Near Net Shaping ◽  
Net Shaping

Ti-5Al-2.5Sn ELI alloy is a typical α titanium, which is widely used at cryogenic temperatures. Hot isostatic pressing (HIPing) is a common technology to fabricate powder metallurgy (P/M) titanium alloys and components. Porosity control is very crucial for P/M alloys during application, and porosity will deteriorate mechanical properties of P/M alloys. In this study, porosity caused by HIPing process has been investigated. Effects of porosity on metallurgy quality of P/M Ti-5Al-2.5Sn ELI alloy have been accessed. The results showed that when porosity levels was less than 0.6%, no significant difference was found comparing with full dense P/M Ti-5Al-2.5Sn ELI alloy. Near-net-shape forming processes of P/M titanium alloy parts ware studied. By using metal capsules and metal internal tooling, near-net-shaping of P/M parts with complex shapes was demonstrated.

Near Net-Shape Forming of Thermal Barrier Coated Components for Gas Turbine Engine Applications

1998 ◽  
Author(s):  
G.E. Kim ◽  
P.G. Tsantrizos ◽  
S. Grenier ◽  
A. Cavasin ◽  
T. Brzezinski
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Gas Turbine ◽  
Bond Coat ◽  
Gas Turbine Engine ◽  
Thermal Barrier ◽  
Forming Process ◽  
Turbine Engine ◽  
Near Net Shape ◽  
Net Shape Forming

Abstract PyroGenesis Inc. has developed a unique Vacuum Plasma Spraying (VPS) near-net-shape forming process for the production of multilayered free-standing components. Initial evaluation on the feasibility of applying this process for the production of gas turbine engine components has been performed. The VPS near-net-shape forming process consists of: selecting an appropriate mold material; preconditioning of mold surface ; depositing metallic, ceramic, or composite layers ; and removing mold from the spray-formed structure. The near-net-shape components are heat treated to improve their mechanical properties. A suitable heat treatment cycle was developed for the VPS-applied superalloy. Much of the recent improvements in gas turbine engine performance has been attributed to the introduction of thermal barrier coatings (TBC) for superalloy components. There exist, however, some limitations in current fabrication methods for closed hot-section components: less than ideal coating quality; welding; limited choice of superalloy material; etc... PyroGenesis has used VPS near-net-shape forming to fabricate closed components with an yttria-stabilized-zirconia inner layer, CoNiCrA1Y bond coat, and IN-738LC outer layer. The results from the initial study demonstrate the feasibility of producing near-net-shape components with good coating structures, superior superalloy materials, and the absence welds. The mold was reusable after minor surface conditioning. The TBC showed uniform thickness and microstructure with a smooth surface finish. The bond coat and structural superalloy layers were very dense with no signs of oxidation at the interface. After heat treatment, the mechanical properties of the IN-738LC compare favourably to cast materials.

Mechanical Properties of Zr-Added Fe-Al Intermetallic Alloys Containing Large Second Phase Particles

2007 ◽  
Vol 561-565 ◽  
pp. 399-402 ◽  
Author(s):  
J. Machida ◽  
Satoru Kobayashi ◽  
Yasuyuki Kaneno ◽  
Takayuki Takasugi
Keyword(s):  
Mechanical Properties ◽  
Room Temperature ◽  
Single Phase ◽  
Tensile Ductility ◽  
Ternary Alloys ◽  
Second Phase ◽  
Intermetallic Alloys ◽  
Fine Grained ◽  
Second Phase Particles ◽  
Al Matrix

Mechanical properties of thermomechanically fabricated D03 Fe-33Al and B2 Fe-38Al intermetallic alloys containing Zr were investigated by means of tensile test and microhardness measurement. The Zr-added ternary alloys showed fine-grained microstructure containing large (Fe,Al)12Zr τ1 phase particles, while the binary alloy showed a single-phase microstructure consisted of coarse recrystallized grains. By introducing the large τ1 phase particles to Fe-Al matrix, tensile strength at room temperature as well as at high temperature (873K) was enhanced but tensile ductility at both temperatures decreased. On the other hand, it was found that vacancy hardening which was significant in the alloys with high contents of Al (i.e., Fe-38Al) was reduced by the large τ1 phase particles.

Research on Process Parameters Optimization of Squeeze Casting for AZ91D Magnesium Alloy

2011 ◽  
Vol 299-300 ◽  
pp. 25-29
Author(s):  
Hui Xu ◽  
Tian Sheng Li
Keyword(s):  
Mechanical Properties ◽  
Process Parameters ◽  
Squeeze Casting ◽  
Phase Particle ◽  
Parameters Optimization ◽  
Second Phase ◽  
Near Net Shape ◽  
Cast Magnesium Alloys ◽  
Cast Magnesium

Cast magnesium alloys are constantly increasing used in the automotive and electronic industry because of the excellent performance. Squeeze casting is an innovative and energy-saving manufacturing process which can be used to produce near net-shape magnesium components. In order to improve the quality of the squeeze casting，the different process parameters were adopted to study the forming property of AZ91D alloy by applying multifactor orthogonal test and analysis of range under the laboratory condition. The metal pouring and die temperatures considered in the investigation were within the range of 680-780 and 300°C respectively. The results showed that the samples’ synthetic mechanical properties was the best, and squeeze casting can refine grain and the second phase particle β(Al12Mg17)separated out more by using mechanical properties test and analyzing microstructure when casting temperature is 730°C, squeezing force is 100 Mpa and time of keeping forces 25s.

Microstructure and Mechanical Properties of ZK60 Magnesium Alloy Prepared by Multi-Pass Friction Stir Processing

2017 ◽  
Vol 898 ◽  
pp. 278-283 ◽  
Author(s):  
Jun Lin ◽  
Da Tong Zhang ◽  
Wen Zhang ◽  
Cheng Qiu
Keyword(s):  
Mechanical Properties ◽  
Magnesium Alloy ◽  
Friction Stir Processing ◽  
Second Phase ◽  
Friction Stir ◽  
Single Pass ◽  
Fine Grained ◽  
Microstructure And Mechanical Properties ◽  
First Pass ◽  
Zk60 Magnesium Alloy

Friction stir processing (FSP) is a novel severe plastic deformation technique developed in recent years to produce fine-grained structural materials. In this paper, the microstructure and mechanical properties of ZK60 magnesium alloy prepared by the single-pass and two-pass FSP were studied. The first-pass was subjected with 800r/min-100mm/min and the second-pass was subjected with 600r/min-100mm/min. The results show that the coarse second phase was dissolved into magnesium matrix and the α-Mg grains were remarkably refined in stir zone after FSP. The average grain sizes of the single-pass and two-pass FSP alloys were 6.8μm and 6.0μm respectively. The microhardnesses of the specimens were 70HV and 65HV, the ultimate tensile strengths were 276MPa and 272MPa, and the elongations were 31.6% and 42.5%, respectively. Through increasing the processing pass, the microstructure became finer and the second phase is dissolved more thoroughly. The combined effect of grain refinement and second phase dissolved was responsible for the change of mechanical properties.

Grain Boundary Characterization in Yttria-Stabilized Zirconia by TEM Spectrum Lines

2000 ◽  
Vol 6 (S2) ◽  
pp. 220-221
Author(s):  
N. D. Evans ◽  
P. H. Imamura ◽  
M. L. Mecartneyf
Keyword(s):  
Grain Boundary ◽  
Tetragonal Zirconia ◽  
Light Element ◽  
Grain Boundary Sliding ◽  
Crystalline Materials ◽  
Fine Grained ◽  
User Facility ◽  
Near Net Shape ◽  
Net Shape Forming ◽  
Boundary Sliding

The superplasticity exhibited by some fine-grained ceramics, notably 3-mol% yttria-stabilized tetragonal zirconia polycrystals (3Y-TZP), offers interesting possibilities to lower manufacturing costs by near net shape forming. Both glassy and crystalline materials have been added to pure 3 Y-TZP to limit grain growth and promote grain boundary sliding during sintering and isostatic pressing. EDS spectrum lines have been used to characterize the distribution and extent of additive phases, but were not able to map some light-element components of additives (e.g., O and B in borosilicate glass). Additionally, quantification of the Si Kα peak was compromised by overlap with the Y L and Z L peaks. To both improve light element sensitivity and investigate potential changes in oxygen bonding at the grain boundaries, undoped 3 Y-TZP and 3 Y-TZP powders processed with 1 wt% barium silicate have been examined with TEM spectrum lines. Additionally, some elemental mapping has been performed. TEM specimens were examined in a 300 kV LaB6 Philips CM30T equipped with a Gatan imaging filter (GIF) at the ORNL SHaRE User Facility.

Sign in / Sign up

Export Citation Format

Share Document