Influence of scandium on superplastic ductilities in an Al–Mg–Sc alloy

2000 ◽  
Vol 15 (11) ◽  
pp. 2571-2576 ◽  
Author(s):  
Shogo Komura ◽  
Zenji Horita ◽  
Minoru Furukawa ◽  
Minoru Nemoto ◽  
Terence G. Langdon
Keyword(s):  
Solid Solution ◽  
Plastic Deformation ◽  
Narrow Range ◽  
Solution Treatment ◽  
Treatment Temperature ◽  
Ultrafine Grain ◽  
Solution Treatment Temperature ◽  
Grain Sizes ◽  
Angular Pressing ◽  
The Matrix

Ultrafine grain sizes, of the order of approximately 0.2 μm, may be introduced into Al–Mg–Sc alloys by subjecting the material to severe plastic deformation through the process of equal-channel angular pressing (ECAP). Experiments were conducted to evaluate the influence of the solution treatment temperature on the ductility of an Al–3% Mg–0.2% Sc alloy after ECAP. The results show the highest ductilities are achieved when the solution treatment temperature is within the narrow range of approximately 878 to about 883 K, immediately below the temperature associated with the onset of partial melting. These high temperatures serve to maximize the amount of scandium in solid solution and this leads, on subsequent heating, to an extensive precipitation of fine secondary Al3Sc particles which inhibit grain growth at the higher temperatures. Conversely, solution treatments at temperatures below approximately 878 K give less Sc in solid solution within the matrix and the precipitation of the Al3Sc particles is then insufficient to retain a uniform ultrafine microstructure.

Effect of Solid Solution Treatment on the Microstructure and Mechanical Properties of IN738LC Superalloy

2011 ◽  
Vol 378-379 ◽  
pp. 744-747 ◽  
Author(s):  
Jeong Min Kim ◽  
Joon Sik Park ◽  
Ho Seob Yun ◽  
Seung Jin Lee ◽  
Seong Uk An
Keyword(s):  
Solid Solution ◽  
Size Distribution ◽  
Solution Treatment ◽  
Treatment Temperature ◽  
Solution Treatment Temperature ◽  
Gamma Prime ◽  
Solid Solution Treatment ◽  
Treatment Conditions ◽  
The Matrix ◽  
Single Size

Cast IN738LC alloy mainly consists of primary gamma matrix, gamma prime precipitates, and carbides. SEM-EDS analysis results suggested that most of the carbides are MC type ones that possess high Ti or Ta contents. MC carbides were partly dissolved into the matrix during the solid solution treatment, and the morphology and size of carbides were influenced by the solid solution treatment temperature. Characteristics of gamma prime precipitates were also significantly affected by the solid solution treatment conditions. Single or duplex size distributions of gamma prime precipitates were obtained depending on the solid solution treatment condition. Higher tensile strength was obtained in the case of finer precipitation size and in the case of single size distribution as compared with that of duplex size distribution.

Effect of Boron Addition on Microstructure and Mechanical Properties of AZ84 Mg Alloy

2016 ◽  
Vol 879 ◽  
pp. 653-658
Author(s):  
Ju Hyun Won ◽  
Seok Hong Min ◽  
Tae Kwon Ha
Keyword(s):  
Mechanical Properties ◽  
Solid Solution ◽  
Solution Treatment ◽  
Treatment Temperature ◽  
Mg Alloy ◽  
Solution Treatment Temperature ◽  
Solid Solution Treatment ◽  
Microstructure And Mechanical Properties ◽  
Peak Aging ◽  
Aging Kinetics

Effect of B addition on the microstructure and mechanical properties of AZ84 Mg alloy was investigated in this study. Through calculation of phase equilibria of AZ84 Mg alloy, carried out by using FactSage® and FTLite database, solution treatment temperature was decided as temperature of 330oC, where supersaturated solid solution can be obtained. Solid solution treatment of AZ84 Mg alloy was successfully conducted at 330oC and supersaturated microstructure with all almost all phases resolved into matrix was obtained. After solution treatment, hot rolling was successfully conducted by reduction of 60%. Compression and tension tests were carried out at room temperature on the samples in as-cast, solution treated, hot-rolled and subsequently recrystallized states. After solid solution treatment, each alloy was soaked at temperatures of 180 and 200oC for time intervals from 1 min to 48 hrs and hardness of each condition was measured by micro-Vickers method. Peak aging conditions were deduced as at the temperature of 200 oC for 10 hrs for ZA84 Mg alloy. By addition of boron, aging kinetics was expedited and strength was enhanced.

Achieving Superplasticity and Superplastic Forming through Severe Plastic Deformation

2000 ◽  
Vol 634 ◽  
Author(s):  
Minoru Furukawa ◽  
Zenji Horita ◽  
Terence G. Langdon
Keyword(s):  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
Elevated Temperatures ◽  
Superplastic Forming ◽  
Ultrafine Grain ◽  
Strain Rates ◽  
Grain Sizes ◽  
Angular Pressing ◽  
Large Bulk ◽  
Processing Procedure

ABSTRACTThe application of severe plastic deformation to metals provides a convenient procedure for achieving nanometer and submicrometer microstructures. Several different processing methods are available but Equal-Channel Angular Pressing (ECAP) is especially attractive because it provides an opportunity for preparing relatively large bulk samples. This paper describes the use of ECAP in preparing materials with ultrafine grain sizes and the subsequent properties of these materials at elevated temperatures. It is demonstrated that, provided precipitates are present to retain these small grain sizes at the high temperatures where diffusion is reasonably rapid, it is possible to achieve remarkably high superplastic elongations in the as-pressed materials and there is a potential for making use of this processing procedure to develop a superplastic forming capability at very rapid strain rates.

Comparative Study on the Properties of CuCoBe Alloy and CuNiCoBe Alloy

2014 ◽  
Vol 988 ◽  
pp. 145-150
Author(s):  
Jian Chen ◽  
Ming Zhang ◽  
Dong Yang ◽  
Huan Liang
Keyword(s):  
Heat Treatment ◽  
Solid Solution ◽  
Solution Treatment ◽  
Optical Microscope ◽  
Treatment Temperature ◽  
Solution Treatment Temperature ◽  
Solid Solution Treatment ◽  
Heat Treated ◽  
Melting Technique ◽  
Different Temperatures

CuNiCoBe alloy and CuCoBe alloy were cast by the vacuum inductive melting technique, and were heat treated under certain parameters. By using optical microscope, sclerometer and conductivity meter, the properties of two alloys were investigated after heat treatment. Experimental results show that the process of 980 °C for solid solution and three hours of aging at 450 °C is the best heat treatment for CuCoBe alloy, while 960 °C is the best solid solution treatment temperature for CuNiCoBe alloy with the same aging measures. Ni is beneficial to improve the hardness and conductivity of alloys, and CuNiCoBe alloy has better strength, hardness and conductivity than CuCoBe alloy at different temperatures, and two alloys all have a conductivity mutation increase near 450 °C. CuNiCoBe alloy and CuCoBe alloy soften respectively at 464 °C and 471 °C.

Effect of Heat Treatment on the Microstructural Characteristics of IN738 Turbine Blade

2011 ◽  
Vol 695 ◽  
pp. 405-408 ◽  
Author(s):  
Ho Seob Yun ◽  
Joon Sik Park ◽  
Seong Uk An ◽  
Jeong Min Kim
Keyword(s):  
Solid Solution ◽  
Size Distribution ◽  
Solution Treatment ◽  
Aging Treatment ◽  
Hardness Test ◽  
Treatment Temperature ◽  
Solution Treatment Temperature ◽  
Gamma Prime ◽  
Average Size ◽  
Single Size

It was observed that both primary and secondary gamma prime precipitates were more significantly influenced by the solid solution treatment temperature as compared to the following cooling rate. Single and duplex size precipitate distribution with different average size could be obtained through the appropriate solid solution and aging treatment. Micro-hardness test result indicated that single size distribution of gamma prime precipitates provides higher hardness than duplex size distribution.

scholarly journals Characterization of Tensile Properties and Fracture Toughness of Equal Channel Angular Pressed Al-Zn Alloy

2021 ◽  
Author(s):  
Mohan kumar S ◽  
H K Govindaraju ◽  
M D Kiran
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Solution Treatment ◽  
Treatment Temperature ◽  
Solution Treatment Temperature ◽  
Artificial Ageing ◽  
Angular Pressing ◽  
Dislocation Strengthening ◽  
Zn Alloy

Abstract Influence of Equal channel angular pressing on mechanical properties and Fracture toughness of Al-Zn alloy were studied in present investigation. Samples are successfully processed using the ECAP technique for up to a four passes by using route A. Al-Zn alloys were heated to a solid solution treatment temperature at 550oC for 2 hours prior to ECAP, this treatment introduces the precipitates which were capable of obstructing motions of dislocation and improves the refinement of the grain during ECAP process Finally, artificial ageing was performed at a temperature of 190°C for 0-20 hours with an interval of 2 hr and specimens are cooledat room temperature with natural air.Fracture toughness was found experimentally for ECAP processed samples using SE (B) specimens according to ASTM E399 standard.Study revealed the enhancement in mechanical properties such as yield strength, ultimate strength and microhardness after four passes by route A technique.The improvement in the fracture toughness properties of artificially aged ECAP samples can also be due to dislocation strengthening, grain boundary strengthening, and the creation of much finer UFG grains, according to the results. Despite the increased tensile strength after ECAP, the ductility behaviour has decreased due to the precipitation of GP zones and dispersion of η, ή, T and E within the Aluminium matrix Furthermore, scanning electron microscope (SEM) micrographs revealed that ductile fracture with large dimples occurred in the artificial aged samples after the ECAP procedure.

scholarly journals Deformation Mechanism Investigation on Low Density 18Mn Steels under Different Solid Solution Treatments

Metals ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1497
Author(s):  
Yong-Tao Huo ◽  
Yan-Lin He ◽  
Na-Qiong Zhu ◽  
Min-Long Ding ◽  
Ren-Dong Liu ◽  
...  
Keyword(s):  
Solid Solution ◽  
Tensile Deformation ◽  
Large Strain ◽  
Solution Treatment ◽  
Strain Range ◽  
Sem Analysis ◽  
Treatment Temperature ◽  
Solution Treatment Temperature ◽  
Experimental Steel ◽  
Δ Ferrite

To meet the demand of the 10% weight reduction goal for automotive steel, the microstructure and mechanical properties of Fe-18Mn-Al-C steel with different carbon and aluminum contents were investigated under different solid solution treatments, and the deformation mechanisms of the experimental steels were elucidated. Aided by thermodynamic calculation, transmission electron microscopy (TEM) and in situ scanning electron microscope (SEM) analysis, it was shown that for the 18Mn-1.5Al experimental steel with about 20 mJ/m2 stacking fault energy (SFE), the twinning-induced plasticity (TWIP) effect always dominated in this steel after different solid solution treatments under tensile deformation. With the 7 wt% aluminum addition, the SFE of austenite was affected by temperature and the range of SFE was between 60 and 65 mJ/m2. The existence of δ-ferrite obviously inhibited the TWIP effect. With the increase in the solution treatment temperature, δ-ferrite gradually transformed into the austenite, and the n-value remained low and stable in a large strain range, which were caused by the local hardening during the tensile deformation. Due to the difference in the deformability of the austenite and δ-ferrite structure as well as the inconsistent extension of the slip band, the micro-cracks were easily initiated in the 18Mn-7Al experimental steel; then, it exhibited lower plasticity.

scholarly journals On the Grain Growth Kinetics of a Low Density Steel

Metals ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 997 ◽  
Author(s):  
Daniel M. Field ◽  
Krista R. Limmer ◽  
Billy C. Hornbuckle
Keyword(s):  
Grain Growth ◽  
Growth Kinetics ◽  
Solution Treatment ◽  
Treatment Temperature ◽  
Solution Treatment Temperature ◽  
Low Density ◽  
Grain Sizes ◽  
Mean Linear Intercept ◽  
Grain Growth Kinetics ◽  
Kinetics Of

The grain growth kinetics of an age-hardenable Fe-Mn-Al-C steel were investigated. Kinetics of grain growth were determined between 1173 and 1348 K (900–1075 °C) to obtain a range of grain sizes from 30 to 475 μm. It was found that grain growth was negligible at 1173 K (900 °C) for times up to 15 h. The activation energy for grain growth was found to be 467 kJ/mol. The hardness and mean linear intercept (L3) were correlated to follow a traditional Hall-Petch relationship. Tensile properties of the alloy were determined after various solution treatments performed for 2 h followed by water quenching. Tensile strength increased from 810 to 960 MPa and ductility was reduced from 80 to 60% as the grain size decreased from 200 μm to 30 μm as grain coarsening was mitigated by lowering the solution treatment temperature.

Extending Creep and Superplasticity to Materials with Submicrometer Grain Sizes

2007 ◽  
Vol 345-346 ◽  
pp. 539-544
Author(s):  
Megumi Kawasaki ◽  
Cheng Xu ◽  
Z. Horita ◽  
Terence G. Langdon
Keyword(s):  
Plastic Deformation ◽  
Aluminum Alloys ◽  
Severe Plastic Deformation ◽  
Flow Behavior ◽  
Ultrafine Grain ◽  
Grain Sizes ◽  
Large Samples ◽  
Angular Pressing ◽  
Recent Advances ◽  
Ultrafine Grained

The mechanisms of creep and superplasticity occurring in conventional large-grained materials are now understood reasonably well. However, very recent advances in the processing of theoretically-dense metals with submicrometer grain sizes have provided the opportunity to extend the understanding of flow behavior to include materials where the grains are exceptionally small. Using processing through the application of severe plastic deformation, as in procedures such as equal-channel angular pressing, it is now feasible to fabricate relatively large samples having ultrafine grain sizes in the submicrometer or nanometer range. This paper examines these recent advances and gives examples of the flow behavior in ultrafine-grained aluminum alloys.

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