Temat: 81.40.Gh - Prolib Integro

Skocz do pozycji: 1.

Tytuł:: Grain Refinement after Various Thermo-Mechanical Treatments in AZ80 and ZK60 Magnesium Alloys
Autorzy:: Ryspaev, T.
Janecek, M.
Minárik, P.
Wesling, V.
Wagner, L.
Kral, R.
Tematy:: 81.40.Gh
81.07.Bc; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:: https://bibliotekanauki.pl/articles/1419057.pdf Link otwiera się w nowym oknie
Opis:: The effect of thermal processing prior to severe plastic deformation by extrusion and swaging on grain refinement in ZK60 and AZ80 alloys was studied. The alloys received in direct-chill cast condition were homogenized at 415C and annealed (over-aged) at temperatures from 200 to 380°C. Both the direct-hill cast and over-aged conditions were extruded at T = 300C using an extrusion ratio of ER = 19. Hot extrusion resulted in substantial grain refinement in both cases, the effect being stronger in the over-aged material. The extruded bars were severe plastically deformed at 250C by swaging. Swaging refined further the grain size depending on the deformation ratio (number of passes). At optimal processing conditions the grain size was 450 nm and 570 nm for the AZ80 and ZK60 alloys, respectively.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 2.

Tytuł:: Effect of aluminum addition to Nb-Al-C-N coatings on AISI M2 steel obtained by thermo-reactive deposition technique
Autorzy:: Abakay, E.
Sen, S.
Sen, U.
Tematy:: 81.40.Gh
81.40.Ef
62.20.Qp
81.05.-t; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:: https://bibliotekanauki.pl/articles/1061918.pdf Link otwiera się w nowym oknie
Opis:: In this study, aluminum-doped (1 and 2 wt.%) and Al-free niobium carbo-nitride coatings were applied to the surface of AISI M2 high speed steel using the process of thermo-reactive deposition technique (TRD) at 1000°C during 1-4 h. The obtained coatings were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) analysis and micro hardness test. Nb-Al-C-N layers were compact and homogeneous. X-ray diffraction analysis has shown that the major phases formed in the coating layer are Nb₂CN and NbN. The depth of the coating layer had increased with the treatment time and ranged from 6.65 to 9.05 μm. The measured values of the hardness of the coating layers were ranging between 2136 and 2636 HK_{0.005}.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 3.

Tytuł:: Atom Probe Tomography Investigations of Modified Early Stage Clustering in Si-Containing Aluminum Alloys
Autorzy:: Pogatscher, S.
Gerstl, S.
Löffler, J.
Uggowitzer, P.
Tematy:: 64.70.kd
61.72.-y
81.40.Gh; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:: https://bibliotekanauki.pl/articles/1402109.pdf Link otwiera się w nowym oknie
Opis:: In this paper atom probe tomography is used to explore early stage clustering in aluminum alloys. Two novel concepts for a modification of clustering are discussed. Control of early stage clustering is welcome from an application point of view since clustering deteriorates strength evolution during the industrial heat treatment of the important class of Al-Mg-Si precipitation-hardenable alloys. Nanoscale early stage clusters are very difficult to observe and atom probe tomography is the best technique to visualize and chemically measure Si or Mg-containing clusters in aluminum alloys. Restrictions remain in achieving the ultimate quantification of such small solute aggregates by atom probe tomography, such as detection efficiency, local magnification effects, surface migration of solute atoms, and unresolved issues with the reconstruction procedure. Here we investigate one of these restricting effects, namely the migration of solute atoms during atom probe tomography measurements. In particular Si is found to be preferentially localized or absent at certain crystallographic poles in aluminum, which derogates the experimental results gained from atom probe tomography studies of clustering in Si-containing aluminum alloys. This artifact is investigated for different specimen temperatures, detection rates and pulse fractions during atom probe tomography measurements. Optimal strategies to analyze small-scale solute clusters in Si-containing aluminum alloys are presented.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 4.

Tytuł:: Annealing Effects after Various Thermo-Mechanical Treatments on Microstructure and Mechanical Properties of Wrought Magnesium Alloy ZK60
Autorzy:: Oo, M.
Janeček, M.
Kral, R.
Wagner, L.
Tematy:: 81.40.Gh
81.07.Bc
61.05.cp; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:: https://bibliotekanauki.pl/articles/1419020.pdf Link otwiera się w nowym oknie
Opis:: The magnesium alloy ZK60 received from Dead Sea Magnesium in direct-chill cast condition was extruded at T = 350C using an extrusion ratio of ER = 12. The extruded bars were severely plastically deformed at 250C by either equal channel angular pressing or swaging. While swaging led to similar grain refinements as observed after equal channel angular pressing, yield stress and tensile strength values were by far superior in the swaged material. This result is explained by the unfavourable 45° texture component of the (0002) pole figure that develops during the massive shear deformation in equal channel angular pressing. Unlike equal channel angular pressing, the grain orientation after swaging is similar as in the as-extruded condition. Annealing at elevated temperatures indicates very low thermal stability of microstructure and mechanical properties in the equal channel angular pressing material while both properties in the swaged microstructure are as stable as in the as-extruded reference.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 5.

Tytuł:: Hot Compression Test of Heat Resistant Steel
Autorzy:: Fedoriková, A.
Kvačkaj, T.
Kočiško, R.
Bidulský, R.
Petroušek, P.
Tematy:: 81.05.Bx
81.40.Gh
81.40.Np
02.70.Dh; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:: https://bibliotekanauki.pl/articles/1032933.pdf Link otwiera się w nowym oknie
Opis:: This article deals with the analysis of formability of heat resistant steel type 9Cr-1Mo by physical laboratory simulation - hot compression test. The 9Cr-1Mo steel belongs to modern 9%Cr tempered martensitic steel for high-temperature applications in advanced thermal power plants. The shape of the sample was defined based on numerical simulations. The laboratory simulation of forming process called physical simulation - specifically hot compression test was realized in the temperature range from 500 to 950°C and total deformation in the range from 39 to 52%. Cracks formed during hot compression test in the notches are assessed. Subsequently, the relation between the compression temperature, strain, and crack length was defined. The suitable workability corresponds to the temperature range 650-900°C, it agrees with results of numerical simulations. At a temperature of 900°C there is marginal relative deformation without rupture ε =39.9%, which corresponds to the value according to simulations NCL criteria 0.501.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 6.

Tytuł:: Microstructure and texture evolution in the welded semi-austenitic PH steel after the heat treatment
Autorzy:: Ziewiec, A.
Witkowska, M.
Zielińska-Lipiec, A.
Tematy:: 81.20.Vj
81.40.Gh
81.40.Ef
68.37.Lp; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:: https://bibliotekanauki.pl/articles/1153207.pdf Link otwiera się w nowym oknie
Opis:: The aim of this study was to reveal the influence of the heat treatment after welding of 17-7PH (X7CrNiAl17-7) steel on the microstructure evolution and the texture of the welds. Microstructure investigation carried out by light microscopy and transmission electron microscopy showed that the austenite and δ ferrite coexist in as-welded condition. Annealing at the temperature range between 400°C and 620°C after welding causes small changes in the microstructure and the hardness of the welds increases. Heat treatment at 760°C for 1 h resulted in the partial destabilization of the austenite. Aging after destabilization leads to tempering of the martensite: first the hardness increases and then decreases. The maximum hardness is observed when the ageing temperature reaches 510°C. XRD studies confirmed the presence of the two phases: δ ferrite and austenite. Annealing at 400°C/1 h and 550°C/1 h results in changes of the intensities for individual peaks derived from austenite and ferrite. The calculated ratios of peak intensity were compared with the intensities of the reference sample. The differences in intensities suggested strong texture of the material.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 7.

Tytuł:: Revealing Prior-Austenite Grain Boundaries and Martensitic Structure of As-Quenched AISI 4140 Steel Treated by Plasma Electrolysis
Autorzy:: Cenk Kumruoglu, L.
Özel, A.
Tematy:: 81.40.Gh
81.40.-z
81.65.Cf
52.50.-b; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:: https://bibliotekanauki.pl/articles/1399956.pdf Link otwiera się w nowym oknie
Opis:: The determination of prior-austenite grain size has been the subject of metallurgical research efforts for many years. Metallurgical laboratories are often required to perform prior-austenite grain size determinations on martensitic steel components that have been heat treated. Although these methods may occasionally be mandated by material or procedural specifications, they are typically not preferred because they have a tendency of altering the as-received microstructure. These processes can also be labour-intensive and costly. The goal of this work is to chemically etch and identify the prior austenite grain size and martensitic structure of AISI 4140 steel treated by plasma electrolysis. Polished samples were immersed in 60% HCl, 30% $HNO_3$, 5% HF, 5% $H_2O$ for 5 seconds then immersed in 5% picric acid, 5% HCl, 90% ethanol to reveal microstructures. Finally, the grain boundary and lath martensitic structure were revealed.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 8.

Tytuł:: Influence of annealing and irradiation by heavy ions on optical absorption of doped lithium niobate crystals
Autorzy:: Potera, P.
Stefaniuk, I.
Tematy:: 81.40.Gh
61.80.-x
78.20.-e; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:: https://bibliotekanauki.pl/articles/1075585.pdf Link otwiera się w nowym oknie
Opis:: The present work is devoted to investigation of optical absorption changes in Fe and Cu doped LiNbO₃ (LNO) single crystals induced during annealing in vacuum and air as well as under influence of the ²⁰⁹Bi ions irradiation with energy 11.4 MeV/u (MeV per nucleon) and a fluence 5×10¹¹ cm¯² at room temperature. The analysis of changes of absorption of the crystal during air annealing have been studied in the Arrhenius coordinates and activation energies have been determined.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 9.

Tytuł:: Chemically Modified Activated Carbons as Catalysts of Oxidative Dehydrogenation of n-Butane
Autorzy:: Malaika, A.
Wower, K.
Kozłowski, M.
Tematy:: 81.05.Rm
81.65.Mq
81.40.Gh
82.65.+r; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:: https://bibliotekanauki.pl/articles/1535911.pdf Link otwiera się w nowym oknie
Opis:: Commercial availability and low price of light alkanes make them very attractive in many branches of industry. Potentially interesting is their use in the process of oxidative dehydrogenation leading to production of olefins. This study was undertaken to characterise the oxidative dehydrogenation of n-butane to 1,3-butadiene (important substrate in production of synthetic rubber and polyamides) taking place over the modified carbon catalysts obtained from peach stones precursor. The catalytic tests were performed in the temperature range 250-450°C at oxygen/n-butane ratio of 1:1. For the majority of the activated carbon samples studied at the lowest temperature the only product was $CO_2$. At 300°C the products of dehydrogenation of n-butane and side products appeared. With increasing temperature the amount of compounds generated increased and in the group of C4 hydrocarbons the dominant were 1-butene and 1,3-butadiene. The most effective catalyst was the sample oxidised with air, the least effective was the sample modified with ammonium peroxydisulphate.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 10.

Tytuł:: Heat treatment of CuFe2 and CuCr0.6 alloys and the effect of precipitates on the grain refinement
Autorzy:: Urbańczyk-Gucwa, A.
Amrogowicz, P.
Jabłońska, M.
Rodak, K.
Tematy:: 81.40.Gh
62.20.F-
61.72.Ff
81.05.Bx
81.40.Rs; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:: https://bibliotekanauki.pl/articles/1075903.pdf Link otwiera się w nowym oknie
Opis:: The results of microstructure and hardness investigations of the CuFe2 and CuCr0.6 alloys after solution and ageing treatment are presented in this paper. The variants of heat treatment as: solution at 1000°C per 3 h and ageing treatment at 500°C for 2 h and at 700°C for 24 h were chosen for severe plastic deformation process realized by rolling with the cyclic movement of rolls method. The structure of CuFe2 and CuCr0.6 alloys was analysed using scanning transmission electron microscopy, and the quantitative studies of the substructure was performed with MET-ILO software, on the basis of images acquired on scanning transmission electron microscope.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Informacja

Wyszukujesz frazę "81.40.Gh" wg kryterium: Temat