Mechanical Properties of Fine-Grained AA1050 after ECAP

2006 ◽  
Vol 503-504 ◽  
pp. 847-852 ◽  
Author(s):  
Stijn Poortmans ◽  
Bert Verlinden

The mechanical properties of fine-grained Aluminium AA1050 produced by ECAP at room temperature, have been investigated under various deformation modes. Because ECAP leads to an unstable microstructure, some samples were annealed at 300°C for 10 minutes in order to stabilise the microstructure. For mechanical testing, cylindrical samples were used in three types of monotonic deformation tests: axisymmetric compression, uniaxial tension and simple shear by torsion. The influence of the deformation mode on the yield locus and strain hardening behaviour has been studied and will be discussed for both hot rolled AA1050, ECAP samples without annealing and annealed ECAP samples. To achieve a better understanding of the strain hardening, some preliminary tests with a change in strain path were also performed. The results of tension tests followed by compression will be reported.

2019 ◽  
Vol 26 (2) ◽  
pp. 249-258 ◽  
Author(s):  
Andrzej Pawlak ◽  
Patrycja E. Szymczyk ◽  
Tomasz Kurzynowski ◽  
Edward Chlebus

Purpose This paper aims to discuss the results of material tests conducted on specimens manufactured from AZ31 alloy powder by selective laser melting (SLM) technology. The manufactured specimens were then subjected to porosity assessment, microstructure analysis as well as to mechanical and corrosion tests. Design/methodology/approach SLM process was optimized using the design of experiments tools. Experiments aimed at selecting optimum process parameters were carried out in accordance with a five-level rotatable central composite design. Findings The porosity results showed very low values of <1 per cent, whereas mechanical properties were close to the values reported for the reference wrought AZ31 alloy in hot-rolled state. A fine-grained microstructure was observed with a large range of grain size, which enhanced the material’s mechanical properties. Corrosion characteristics of the SLM-manufactured material exceed those determined for the wrought material. Originality/value The results presented in this paper drive interest in magnesium alloys used in additive manufacturing processes. Low porosity, good mechanical properties, form of the microstructure and, most importantly, improved corrosion characteristics suggest that SLM provides great potential for the manufacture of ultralight structures, including resorbable metallic implants.


2010 ◽  
Vol 654-656 ◽  
pp. 1255-1258 ◽  
Author(s):  
Dmitry Orlov ◽  
Rimma Lapovok ◽  
László S. Tóth ◽  
Ilana B. Timokhina ◽  
Peter D. Hodgson ◽  
...  

As-received hot-rolled 5.6 mm thick IF steel sheet was symmetrically/asymmetrically cold rolled at room temperature down to 1.9 mm. The asymmetric rolling was carried out in monotonic (an idle roll is always on the same side of the sheet) and reversal (the sheet was turned 180º around the rolling direction between passes) modes. Microstructure, texture and mechanical properties were analysed. The observed differences in structure and mechanical properties were modest, and therefore further investigation of the effects of other kinds of asymmetry is suggested.


1991 ◽  
Vol 6 (12) ◽  
pp. 2653-2659 ◽  
Author(s):  
G.M. Pharr ◽  
S.V. Courington ◽  
J. Wadsworth ◽  
T.G. Nieh

The mechanical properties of nickel beryllide, NiBe, have been investigated in the temperature range 20–820 °C. The room temperature properties were studied using tension, bending, and compression tests, while the elevated temperature properties were characterized in compression only. NiBe exhibits some ductility at room temperature; the strains to failure in tension and compression are 1.3% and 13%, respectively. Fracture is controlled primarily by the cohesive strength of grain boundaries. At high temperatures, NiBe is readily deformable—strains in excess of 30% can be achieved at temperatures as low as 400 °C. Strain hardening rates are high, and the flow stress decreases monotonically with temperature. The high temperature strength of NiBe is as good or better than that of NiAl, but not quite as good as CoAl.


2011 ◽  
Vol 236-238 ◽  
pp. 1939-1944
Author(s):  
Pei Qing La ◽  
Xin Guo ◽  
Yang Yang ◽  
Chun Jie Cheng ◽  
Xue Feng Lu ◽  
...  

Microstructure and mechanical properties of bulk nanocrystalline Fe3Al based alloy with 10 wt. % Mn prepared by aluminothermic reaction after annealing at 600, 800 and 1000°C for 8 h were investigated in order to gain insights in effects of annealing. Crystal structure of the alloy did not change and a fiber phase with enriched Mn appeared in the annealed alloy. Grain size of the alloy changed a little after annealing at 600°C but increased a lot after annealing at 800 and 1000°C. The annealed alloy had plasticity in compression at room temperature and the alloy annealed at 1000°C had yield strength of 782 MPa. The alloy without annealing has creep properties in compression at 800 and 1000°C and can be easily hot rolled to strip and sheet.


2014 ◽  
Vol 788 ◽  
pp. 406-413 ◽  
Author(s):  
Yun Zhou ◽  
Xue Min Wang ◽  
Xin Lai He

Multiphase steels were obtained by using Gleeble-1500 simulator and TMCP, and were characterized by optical microscopy, SEM, TEM, EBSD (electron back-scattered diffraction) and other tests to investigate its microstructure and mechanical properties. During the simulation, the deformation temperature is 850°C, and the steels are air cooled to 750-600°C and then quenched to room temperature. The results indicate that the microstructure of the specimen is composed of ferrite and bainite. With the lowering of quenching temperature, the proportion of ferrite increases and the proportion of bainite decreases, and the bainite laths is shorter. The fine (Nb, Ti) C particles and dislocations appear in ferrite and lath bainite, and the amount of high angle grain boundary decrease after the initial increasing. The microaolloyed hot-rolled multiphase steel plate was developed by two-stage rolling, subsequently quenching to room temperature or air cooling to 600°C, then quenching to room temperature. Two typical microstructures: acicular ferrite and ferrite-bainite multiphase were obtained. The ferrite-bainite multiphase steel showed better mechanical properties, and the yield strength, tensile strength, yield ratio, uniform elongation and percentage elongation were 488Mpa, 845Mpa, 0.58, 10.3% and 21% respectively. The refinement of bainite structures, fine (Nb, Ti) C particles and the dislocations in bainite increase the strength.


1989 ◽  
Vol 10 (2) ◽  
pp. 135-152 ◽  
Author(s):  
W. Y. Yeung ◽  
J. Hirsch ◽  
M. Hatherly

The rolling textures and microstructures developed in fine grained (2–5 μm diam.) 70:30 brass are different to those found in coarser grained material. The {111}〈uvw〉γ fibre usually found at medium reductions is not developed but the normal {110}〈112〉 texture still emerges at higher reductions. The microstructures are related to these changes. Although twinning is a deformation mode at low reductions the volume of twins is never large and the twin alignment characteristic of normal brass at ∼70% reduction does not occur. The pattern of shear band development is changed and large areas of the microstructure are featureless at high reductions. Hardness values show an unexpected rise between 60 and 90% reduction and this is attributed to a Stage IV regime of strain hardening. After annealing at 300 and 900℃ the textures are typical of those found in coarser grained material.


2009 ◽  
Vol 475 (1-2) ◽  
pp. 126-130 ◽  
Author(s):  
S.M. Fatemi-Varzaneh ◽  
A. Zarei-Hanzaki ◽  
M. Haghshenas

2000 ◽  
Vol 646 ◽  
Author(s):  
Y. Kaneno ◽  
T. Takasugi

ABSTRACTB2-type CoTi intermetallic compound that was hot-rolled and recrystallized was tensile-tested as functions of temperature and testing atmosphere. The tensile strength showed a peak at intermediate temperature (∼800K). The brittle-ductile transition (BDT) defined by tensile elongation took place at about 800K, above which large tensile elongation was observed. Corresponding to this transition, SEM fractography showed a change from cleavage-like pattern mixed with intergranular fracture pattern to large cross-sectional reduction, i.e. necking of the tensile specimen. Also, the observed mechanical properties were independent of heat-treatment procedures, indicating that retained vacancies did not affect the mechanical properties of CoTi intermetallic compound. However, the tensile elongation and UTS at room temperature were dependent on testing atmosphere, indicating that moisture-induced embrittlement occurred in CoTi intermetallic compound.


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