specjalne Metody nieograniczonego odkształcania plastycznego materiałów

Severe Plastic Deformation (SPD)

is an approach that refines grains and other structural features through plastically deforming materials to a very large strain.

Metoda CWS (CEC method)

Old process

CEC - new process

>>Opis metody w>> INNOWACYJNE METODY PRZERÓBKI PLASTYCZNEJ METALI Książka_2010

Rys. 1.16. Narzędzia i warunki realizacji procesów CWS na prasie hydraulicznej;

F_e – siły procesu, F_c – siły przeciwnacisku, F_t – siły docisku narzędzi, v – prędkość przemieszczenia stempli

Fig.1

6082

15 c

Fig.2

6082

9 c

J. Richert: Strain-stress conditions of shear band formation during CEC processing on a new machine with control back-pressure,

Archives of Matalurgy and Materials 55(2010)2, 391-408 http://www.imim.pl/archives

“Fig. 15. Graphic representation of the directions of the shear band formation in the deformation zone of CEC processes”

Research novelties: At the present time, the CEC processes are realized by using hydraulic original press P-CWS2, made by BRYDEX company (Poland) (Fig.3). The press characterizes the microprocessor steering (Fig.4, Fig.5) and the computer recording (Fig.6) of measured parameters of process. The "intelligent ” control computer programme, automatically regulating the hydrostatical pressure necessary for preservation of metal cohesion during all cycles of the CEC deformation, is now tested. The AlMgSi alloy 6082 was deformed. The amazing success was got, which resulted from use of press P-CEC 2, instead of device D-CEC 1 (visible above). The numerous intersecting shear bands were found on the whole external surface of deformed samples. These bands are very visible (without etching!). The photos (Fig.1, Fig.2), prepared by digital camera (Konica Minolta Z5), present two samples of 10 mm diameter after 15 and 9 cycles of CEC process (8,5 mm diameter of die)

Nowości badawcze: Procesy CWS realizowane są obecnie na oryginalnej prasie hydraulicznej AGH / P-CWS2, wykonanej przez firmę BRYDEX (Fig.3). Prasa charakteryzuje się mikroprocesorowym sterowaniem (Fig.4, Fig.5) oraz komputerową rejestracją (Fig.6) mierzonych parametrów procesu. Obecnie testuje się także „inteligentny” sterowniczy program komputerowy, który automatycznie reguluje ciśnienie hydrostatyczne niezbędne do zachowania spójności odkształcanego metalu we wszystkich cyklach procesu. Odkształcaniu poddawano stop AlMgSi 6082 (PA4). Uzyskano rewelacyjny sukces wynikający z użycia prasy P-CWS2, zamiast urządzenia U-CWS1 (widocznego powyżej). Stwierdzono, że na całej zewnętrznej powierzchni odkształcanych próbek występują liczne przecinające się pasma ścinania. Te pasma są bardzo widoczne (bez trawienia !). Na zdjęciach (Fig.1, Fig.2), wykonanych aparatem cyfrowym (Konica Minolta Z5), przedstawiono dwie próbki o średnicy 10 mm (ze stopu 6082) po 15 i 9 cyklach procesu CWS (średnica matrycy 8,5 mm).

Fig.3 Fig.4

Fig.5 Fig.6

Processing Metals by Severe Plastic Deformation Andrzej Rosochowski

Processing Metals by Severe Plastic Deformation. Andrzej Rosochowski a). Design, Manufacture and Engineering Management, University of Strathclyde, ...
www.scientific.net/SSP.101-102.13.pdf

Maria Richert, Andrzej Korbel<Kliknij Całość pub. PDF dot. metody CWS:

ELSEVIER J. of Mat Proc. Technology 53 (1955) 331-340

Microstructural evolution over a large strain range in aluminium deformed by cyclic-extrusion–compression

M. Richert, Q. Liu, N. Hansen, Materials Science and Engineering A260 (1999) 275–283

M. Richert, H.P. Stüwe, J. Richert, R. Pippan, Ch. Motz:CHARACTERISTIC FEATURES OF MICROSTRUCTURE OF AlMg5 DEFORMED TO LARGE PLASTIC STRAINS (ABSTRACT) Materials Science and Engineering, A301, 237-243 (2001)

>>>>Całość tej publikacji w PDF

Fig. 9.

Fig. 9. Inverse pole figure maps of misorientation comprise the range of true strains j = 0.2–16 (corresponding to 0.5–38 cycles of the CEC method). The colours correspond to orientations distinguish on the basic triangle, placed at the bottom of the figure. The blue colour fits the <111> orientation; a green fits the <011> and the red fits the <001> orientation.

Metoda wyciskania do kanału kątowego

SPD Processing and Properties of Metastable Nanostructured Alloys (pdf) R.Z. Valiev

The Three-Dimensional Simulation of Flow Pattern in Equal-Channel Angular Extrusion,(HTML)

H.J. Cui, R.E. Goforth, and K.T. Hartwig -1)

1) 2)

Grain Refinemement and Mechanical Properties at Elevated Temperature of Al-Mg Alloy by Hard-Strain-Process 2)

(AA5056 - Kawazoe M.)

STWW-IWT project... Ultra Fine Structured Metallic Materials transformation under simple shear (b) and experimental distortion of co-ordinate grid (c). Source: V.M. Segal, Materials Science and Engineering A17, 1995, 157-164. Objectives Scientific objectives The main scientific objective is to develop metallic ...

Ultra fine structured (UFS) materials are polycrystals with a grain size below about 1 µm. The term nanostructured materials is used for UFS materials with a grain size between 2 nm and 100 nm, and the term sub-micron materials for grain sizes between 100 nm and 1 µm. Besides dramatic increases in strength and toughness, significant changes in physical properties have been observed in UFS materials when compared with the corresponding conventionally produced coarser grain counterparts.

Equal channel angular processing (a), element transformation under simple shear (b) and experimental distortion of co-ordinate grid (c).
Source: V.M. Segal, Materials Science and Engineering A17, 1995, 157-164.

Microstrutural Control of an Al-Mg-Si Alloy using Equel-Channel Angular Pressing

Materials Science Forum V.396-402 (2002) 333-338 Trans Tech Publictions, Switzerland

Effect of Mg Additions on the Work Hardennig Behavior of Aluminium over a Wide Range of Strain Materials Science Forum V.396-402 (2002) 1007-1012 Trans Tech Publictions, Switzerland

Equal Channel Angular Extrusion (ECAE) - A new feedstock production route

a) As-cast Showa A390 deformed by ECAE and heated to 567°C/10 min b) As-cast Cu-0.1% O-0.5%Te deformed by ECAE and heated to 1071°C for 1 hour

a) As-cast Showa A390 deformed by ECAE and heated to 567°C/10 min ^;

b) As-cast Cu-0.1% O-0.5%Te deformed by ECAE and heated to 1071°C for 1 hour ^

Metoda cyklicznego walcowania wielowarstwowego materiału

NOVEL ULTRA-HIGH STRAINING PROCESS FOR BULK MATERIALSÐDEVELOPMENT OF THE ACCUMULATIVEROLL-BONDING (ARB) PROCESS

Y. SAITO, H. UTSUNOMIYA{, N. TSUJI and T. SAKAI

Acta mater. Vol. 47, No. 2, pp. 579±583, 1999 Acta Metallurgica Inc.

Abstract: A novel intense plastic straining process named accumulative roll-bonding (ARB) is proposed.(..)

Special processes such as cyclic extrusion compression (CEC) [1], equal channel angular press (ECAP) [2] and torsion straining under high pressure (TS) [3] have already been proposed as intense plastic straining and successfully applied to various materials.(...)

REFERENCES

1. Richert, J. and Richert, M., Aluminium, 1986, 62, 604.

2. Valiev, R. Z., Krasilnikov, N. A. and Tsenev, N. K., Mater. Sci. Engng, 1991, A137, 35.

3. Horita, Z., Smith, D. J., Furukawa, M., Nemoto, M.,Valiev, R. Z. and Langdon, T. G., J. Mater. Res.,1996, 11, 1880.

“Amorphous Aluminum Alloys—Synthesis and Stability” by John H. Perepezko and Rainer J. Hebert

[39. R.S. Mishra et al., editors, Ultrafine Grained Materials (Warrendale, PA: TMS, 2000)]

A schematic illustration of the cold-roll and fold process (A multilayer of elemental foils with foil thicknesses between 7 µm and 25 µm is reduced by 50% with each rolling pass)

CRYSTAL PLASTICITY MODELLI Accumulative Roll-bonding (ARB) Process

Format pliku: PDF/Adobe Acrobat... A number of techniques, such as cyclic extrusion-compression (CEC) (Korbel, Richert and Richert 1981), high pressure torsion (Winther, Hansen, Hebesberger ...

Low Temperature Superplasticity of Ultra-Fine Grained 5083 Aluminium Alloy Produced by Accumulative Roll-Bonding