scholarly journals EFFECT OF TREATMENT SOLUTION ON THE MICROSTRUCTURE AND MICROHARDNESS OF TERNARY Ni-Al-Nb ALLOY DOPED WITH TITANIUM

2021 ◽  
Vol 22 (1) ◽  
pp. 1
Author(s):  
Hikmat Nugraha ◽  
Pradoto Ambardi ◽  
Djoko Hadi Prajitno
Keyword(s):  
Solution Treatment ◽  
High Strength ◽  
Optical Microscope ◽  
Titanium Content ◽  
Air Cooling ◽  
Gamma Prime ◽  
Titanium Nickel ◽  
Effect Of Treatment ◽  
Hardness Values

EFFECT OF TREATMENT SOLUTION ON THE MICROSTRUCTURE AND MICROHARDNES OF TERNARY Ni-Al-Nb ALLOY DOPED WITH TITANIUM. Nickel-based superalloys have been widely used in various applications, which require high strength at high temperatures. Most types of these superalloys is age-hardenable because they have γ’ particles' chemical composition Ni3(Al, Ti) in γ’-phase matrix. This research will be used alloy Ni-Al-Nb added alloying elements Ti. This research was conducted to study the mechanical properties, microstructure conditions in some alloys Ni-Al-Nb added distinction Titanium element (0,5% and 1% Ti) using the method of aging temperature variation performed at a temperature of 650 °C,700 °C and 750 °C with a holding time 4 hours and air cooling. Tests were conducted to determine the characterization of the specimen includes testing metallographic optical microscope, Rockwell hardness C and SEM- EDS,XRD. Results obtained from this research that addition of titanium element affecting the hardness values as well as the results of the cast, solution treatment and aging process results. The 1% Titanium content can affect the gamma prime coarsening and make the grain on the microstructure result smooth.

Effect of cooling rates of solution treatment on rejuvenation heat-treated microstructures of a cast nickel-based superalloy

2021 ◽  
Vol 63 (2) ◽  
pp. 105-112
Author(s):  
Chuleeporn Paa-rai ◽  
Gobboon Lothongkum ◽  
Panyawat Wangyao
Keyword(s):  
Solution Treatment ◽  
Spherical Shape ◽  
Irregular Shape ◽  
Air Cooling ◽  
Gamma Prime ◽  
Nickel Based Superalloy ◽  
Heat Treated ◽  
Two Temperatures ◽  
Cooling Media

Abstract IN-738 turbine blade samples, deteriorated after long term service at high temperatures, were solution heat-treated at two temperatures, 1398 K and 1473 K, for 7.2 ks. Subsequently, the samples were cooled down in different atmospheres, in air and in furnace, for the purpose of studying the effects of different cooling media (rates) on the restored microstructures. Following this, the samples were aged at 1118 K for 43.2 ks and 86.4 ks in order to determine the characteristic of re-precipitated gamma prime particles. A scanning electron microscope (SEM) and ImageJ analysis software were used. The results show that the cooling in air provided gamma prime particles re-precipitating in spherical shape while the cooling in a furnace resulted in coarse gamma prime particles re-precipitating in irregular shape. The samples solutionized at 1398 K for 7.2 ks cooled down in air and then aging at 1118 K provided bimodal microstructure, while the sample solutionized at 1473 K for 7.2 ks, followed by air cooling and aging at 1118 K generated unimodal γ’ precipitation in spherical shape. Cooling in a furnace provides coarse γ’ recipitated particles in more irregular shape for the both solutionizing temperatures studied here. Cooling in a furnace provides coarse γ’ precipitated particles in more irregular shape for the both solutionizing temperatures studied here.

Effect of Solution Treatment on Microstructure and Mechanical Hardness of Ti-6Al-7Nb

2020 ◽  
Vol 860 ◽  
pp. 218-222
Author(s):  
Della Maharani ◽  
Anawati Anawati ◽  
I. Nyoman Jujur ◽  
Damisih
Keyword(s):  
Centrifugal Casting ◽  
Solution Treatment ◽  
Aging Treatment ◽  
Xrd Analysis ◽  
Optical Microscope ◽  
Alloying Element ◽  
Mechanical Hardness ◽  
Β Phase ◽  
Permanent Implant

The metastable β Ti-6Al-4V alloy has been used clinically as a permanent implant material owing to its suitable mechanical properties and biocompatibility. However, the alloying element V was accused of causing toxicity when released to human body fluid. In this work, Nb was used in the alloy to replace V. This study presents the characterization of microstructure and mechanical hardness of as-cast Ti-6Al-7Nb and after solution treatment. The Ti-6Al-7Nb alloy was fabricated by the centrifugal casting method. Solution treatment was carried out at 970°C for 1 hour, followed by oil quenching, and consecutively an aging treatment was applied at 500°C for 8 hours. The microstructure was studied by an optical microscope. The mechanical hardness was measured by microhardness Vickers. The results show that the mechanical hardness of the Ti-6Al-7Nb decreased from 396.2 to 377.2 HV as a result of the solution treatment. Reduction in the hardness was attributed to the phase transformation of α to the β phase during the solution treatment. The XRD analysis showed a reduction in the intensity of α phases at the (011), (012), and (020) planes in the alloy after the solution treatment. The results indicated that the microstructure and mechanical hardness of Ti-6Al7-Nb alloy were affected by the solution treatment.

Age-Hardening Characteristics of Cu-3Ag-0.5Zr Alloy

2012 ◽  
Vol 710 ◽  
pp. 563-568 ◽  
Author(s):  
S. Chenna Krishna ◽  
K. Thomas Tharian ◽  
Bhanu Pant ◽  
Ravi S. Kottada
Keyword(s):  
Electrical Conductivity ◽  
Rocket Engine ◽  
Copper Alloys ◽  
Solution Treatment ◽  
Aging Treatment ◽  
High Strength ◽  
Average Diameter ◽  
Age Hardening ◽  
Liquid Rocket

Among the copper alloys, the Cu-3Ag-0.5Zr alloy is one of the potential candidates for combustion chamber of liquid rocket engine because of its optimum combination of high strength with thermal conductivity. The present study is a detailed characterization of microstructure, strength, and electrical conductivity during the aging treatment. The aging cycle for Cu-3Ag-0.5Zr alloy after the solution treatment (ST) was optimized to obtain higher hardness without compromising on electrical conductivity. The precipitates responsible for strengthening in aged samples are identified as nanocrystalline Ag precipitates with an average diameter of 9.0±2.0 nm.

scholarly journals A study of mechanical properties of titanium alloy Ti-6al-4v used as dental implant material

2017 ◽  
Vol 3 (11) ◽  
pp. 288 ◽  
Author(s):  
Hosam Alegaly Alaraby ◽  
Magdi Mohamad A Lswalhia ◽  
Tajammul Ahmed
Keyword(s):  
Titanium Alloy ◽  
Dental Implant ◽  
Volume Fraction ◽  
Solution Treatment ◽  
High Strength ◽  
Optical Microscope ◽  
Temperature Phase ◽  
Implant Material ◽  
Implant Dentistry ◽  
The Right

<p class="abstract"><strong>Background:</strong> Titanium and its alloys are being extensively researched and are applied relatively in different fields of dentistry since 1970s. Its inherent advantages like high strength, ductility, low modulus of elasticity, ease of formation of oxidized surface layer, ability to retain mechanical integrity after autoclave and relatively low toxicity has led to extensive application of titanium and its alloys in implant dentistry.</p><p class="abstract"><strong>Methods:</strong> The Titanium alloy Ti-6Al-4V dental implant material used for the present study was procured from Mishra Dhatu Nigam (Midhani, Hyderabad). The mechanically polished samples were etched using Kroll’s reagent (5% hydrofluoric acid+10% nitric acid+85% water). The etched specimens were examined under optical microscope.  </p><p class="abstract"><strong>Results:</strong> The primary α phase being the low temperature phase, is stable and shows single phase microstructure. The size and volume fraction of the primary α and transformed β phases depend on the solution treatment temperatures and the subsequent rate of cooling.</p><p><strong>Conclusions:</strong> The success of the treatment modality relies on the knowledge of the properties required to employ them at the right situation. </p>

Long term heating effects at 1173 K and 1273 K on microstructural rejuvenation in various modified alloys based on GTD-111

2021 ◽  
Vol 63 (8) ◽  
pp. 691-698
Author(s):  
Vara Vacharatanon ◽  
Napat Kiatwisarnkij ◽  
Gobboon Lothongkum ◽  
Nuthaporn Nuttayasakul ◽  
Jiaqian Qin ◽  
...  
Keyword(s):  
Research Work ◽  
Solution Treatment ◽  
Nickel Base Superalloy ◽  
Air Cooling ◽  
Gamma Prime ◽  
Treatment Conditions ◽  
Heating Effects ◽  
Reheat Treatment ◽  
Nickel Base

Abstract This research work studied and evaluated the effects of reheat treatment conditions, which consisted of solution treatment at a temperature of 1448 K for 14.4 ks, followed by air cooling and precipitate aging at a temperature of 1118 K for 86.4 ks, on the microstructural rejuvenation or refurbishment of various modified alloys based on the cast nickel base superalloy, GTD-111 with aluminum, nickel and/or cobalt additions after long term heating at temperatures of 1173 K and 1273 K for 1440 ks. From the results obtained, it was found that the reheat treatment conditions applied are more suitable for microstructures after long term heating at a temperature of 1173 K. However, such reheat treatment conditions could not fully return reheat treated microstructures to microstructures similar to those of previous research work. It seems that the selected solutioning temperatures and/or times were not sufficient to completely dissolve all coarse gamma prime particles after long term heating for all samples with alloying additions. Typical size and area fractions of the gamma prime particles of the reheat treated microstructures are very similar to those of the original alloyed ones but with lower values, especially those related to the size of the gamma prime particles.

Influence of Solution Conditions on Aging Response of Ti-3.5Al-5Mo-4V-2Cr-1Fe-2Zr-2Sn Titanium Alloy

2010 ◽  
Vol 146-147 ◽  
pp. 1815-1820 ◽  
Author(s):  
Peng Ge
Keyword(s):  
Titanium Alloy ◽  
Solution Treatment ◽  
High Strength ◽  
Age Hardening ◽  
Air Cooling ◽  
Beta Titanium Alloy ◽  
Beta Titanium ◽  
Aging Response ◽  
Aging Conditions ◽  
Metastable Beta

Ti-3.5Al-5Mo-4V-2Cr-1Fe-2Zr-2Sn titanium alloy is a new high strength metastable beta titanium alloy which was designed according to the principle of ‘near critical molybdenum equivalent and multicomponent strengthening’. The effect of solution treatment on aging responses of the new alloy including room temperature tensile properties and microstructures were investigated. There is a tendency that the tensile strength is increasing with the increase of solution temperatures on the same aging conditions and water quenching from solution temperatures can produce higher age hardening effect than that treated by air cooling. The results revealed that the specific aging response of the new alloy is from the high driving force of phase precipitation together with the effect of excess vacancies.

scholarly journals Influence of Preaging Treatment on Bake-Hardening Response and Electrochemical Corrosion Behavior of High Strength Al-Zn-Mg-Cu-Zr Alloy

Metals ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 895 ◽  
Author(s):  
Hui Li ◽  
Xiao-Teng Liu ◽  
Jia-Yi Wang
Keyword(s):  
Corrosion Behavior ◽  
Potentiodynamic Polarization ◽  
Electrochemical Impedance ◽  
Solution Treatment ◽  
Natural Aging ◽  
Electrochemical Corrosion ◽  
High Strength ◽  
Optical Microscope ◽  
Bake Hardening ◽  
Na Effect

The influence of preaging (PA) treatments on the bake hardening (BH) response of a AlZnMgCuZr aluminum alloy which served as automotive body structures were studied in this paper. A novel two-step PA treatment was particularly designed and further employed. The mechanical properties of the alloy were tested in detail. The microstructure was characterized by optical microscope (OM), transmission electron microscopy (TEM) and 3D measuring laser microscope (3D–MLM). Meanwhile, the corrosion behavior was investigated by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. The results indicated that the PA treatment was beneficial for the improvement of BH response after baking at 180 °C immediately after the solution treatment and the micro-hardness reached the peak value (194 HV) after 10 h holding, which had a percentage improvement of 110.87% compared to the hardness under the solution condition. The PA treatments decreased natural aging (NA) adverse effects, while it had the lowest NA effect and optimal BH response under 120 °C/20 min. Such a novel two-step PA treatment was revealed further to decrease the NA effect and increase the BH response compared to the optimal PA treatment, in particular, the BH value could reach 168 MPa and was 21.7% higher than that of optimal PA + NA treatment. The optimal corrosion resistance has been shown up by the combined characterizations of potentiodynamic polarization curves, EIS Nyquist plots, and 3D–MLM images.

Effect of Cooling Rate and Aging Process on Wear Behavior of Deformed TC21 Ti-Alloy

2020 ◽  
Vol 835 ◽  
pp. 265-273
Author(s):  
Ramadan N. Elshaer ◽  
Khaled M. Ibrahim ◽  
Ibrahim Lotfy ◽  
Mahmoud Abdel-Latif
Keyword(s):  
Wear Rate ◽  
Cooling Rate ◽  
Wear Behavior ◽  
Solution Treatment ◽  
Weight Ratio ◽  
High Strength ◽  
Air Cooling ◽  
Aerospace Applications ◽  
Treatment Techniques ◽  
Solution Treated

TC21 with a composition of Ti-6Al-3Mo-1.9Nb-2.2Sn-2.2Zr-1.5Cr is considered a new titanium alloy that is used in aerospace applications as a replacement for the famous Ti-6Al-4V alloy due to its high strength-to-weight ratio, high operating temperature and corrosion resistance. In this study, two different solution treatment techniques were applied on TC21 samples. Solution treatment was applied using two step heating at 1000/800 °C for 15 min each and then cooled using water quenching or air cooling to see the effect of cooling rate on microstructure as well as mechanical properties. The solution treated samples were divided into two groups; one was tested as solution treated samples without aging. While, the second group was aged at 575 °C for 4 hrs. Maximum hardness of 442 HV was observed for the water quenched and aged samples, while the minimum hardness of 340 HV was obtained for water quenched samples without aging. The lowest wear rate was obtained for water quenched and aged samples. However, the highest wear rate was reported for the samples solution treated and water quenched without aging.

Effect of Cooling Medium on Solution Treatment Response of Titanium Alloy Ti-5Al-5V-2Mo

2015 ◽  
Vol 830-831 ◽  
pp. 123-126 ◽  
Author(s):  
V. Anil Kumar ◽  
R.K. Gupta ◽  
J. Paul Murugan ◽  
J. Srinath ◽  
Sushant K. Manwatkar ◽  
...  
Keyword(s):  
Titanium Alloy ◽  
Titanium Alloys ◽  
Solution Treatment ◽  
High Strength ◽  
Pressure Vessels ◽  
Treatment Temperature ◽  
Water Quenching ◽  
Air Cooling ◽  
Solution Treatment Temperature ◽  
Stress Relieving

Titanium alloys are widely used in aerospace industry in the areas of pressure vessels, airframe structures, landing gears, aeroengine compressor blades etc. The principal qualities of titanium alloys required for these applications are high specific strength, low density and high specific modulus. Among the families of Ti alloys, high strength titanium alloys come under martensitic α + β and metastable β alloys. Titanium alloy Ti-5Al-5V-2Mo (BT-23) is an important example of martensitic α + β alloy similar to the work horse Ti6Al4V alloy which exhibits good combination of strength and ductility in solution treated and aged conditions. But due to quenching from solution treatment temperature, the alloy tends to retain good amount of residual stresses. The severity of residual stress increases with increase in solution treatment temperature as well as severity of quench. An attempt has been made to study the effect of air cooling subsequent to solution treatment to compare the strength of the alloy vis-à-vis that achievable during water quenching. An attempt has also been made to correlate the microstructure evolution, hardness with variation in solution treatment temperature and quench severity in titanium alloy Ti-5Al-2Mo-5V. Samples subjected to air cooling subsequent to solution treatment exhibited higher microhardness when compared to water quenched samples. It is proposed that dynamic aging and/ or stress relieving occurs during air cooling from solution treatment temperature down to room temperature. Also the fine α precipitates formed during air cooling may be resulting in higher hardness compared to the α’’/α’ formed during water quenching. The same has been supported by thermal analysis of air cooling and water quenching processes employed subsequent to solution treatment.

A TEM microscopical investigation of the magnetic domain structure of a metastable austenitic stainless steel

1994 ◽  
Vol 52 ◽  
pp. 696-697
Author(s):  
G. Fourlaris ◽  
T. Gladman
Keyword(s):  
Tensile Strength ◽  
Stainless Steel ◽  
Austenitic Stainless Steel ◽  
Cold Rolling ◽  
Solution Treatment ◽  
Magnetic Domain ◽  
High Strength ◽  
Medium Carbon Steel ◽  
Magnetic Characteristics ◽  
Metastable Austenitic Stainless Steel

Stainless steels have widespread applications due to their good corrosion resistance, but for certain types of large naval constructions, other requirements are imposed such as high strength and toughness , and modified magnetic characteristics.The magnetic characteristics of a 302 type metastable austenitic stainless steel has been assessed after various cold rolling treatments designed to increase strength by strain inducement of martensite. A grade 817M40 low alloy medium carbon steel was used as a reference material.The metastable austenitic stainless steel after solution treatment possesses a fully austenitic microstructure. However its tensile strength , in the solution treated condition , is low.Cold rolling results in the strain induced transformation to α’- martensite in austenitic matrix and enhances the tensile strength. However , α’-martensite is ferromagnetic , and its introduction to an otherwise fully paramagnetic matrix alters the magnetic response of the material. An example of the mixed martensitic-retained austenitic microstructure obtained after the cold rolling experiment is provided in the SEM micrograph of Figure 1.

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