Wyniki wyszukiwania - BazTech

1

Obróbka cieplno-plastyczna odkuwek ze stali mikrostopowych

Opiela M.

Stal, Metale & Nowe Technologie

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2017

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nr 11-12

34--39

PL

W pracy przedstawiono wyniki badań wpływu obróbki cieplno-plastycznej przez kucie na strukturę i własności mechaniczne nowo opracowanej stali mikrostopowej zawierającej: 0,31% C, 1,41% Mn, 0,033% Ti, 0,008% V i 0,003% B. Zastosowana obróbka cieplno- plastyczna pozwala na uzyskanie drobnoziarnistej struktury austenitu podczas odkształcenia plastycznego na gorąco oraz wytwarzanie odkuwek uzyskujących po kontrolowanym chłodzeniu z temperatury końca obróbki plastycznej i następnym wysokim odpuszczaniu korzystny zespół własności mechanicznych i gwarantowaną odporność na pękanie. Odkuwki wytworzone metodą obróbki cieplno-plastycznej poddane następnie odpuszczaniu w zakresie temperatury od 550 do 650°C wykazują: Rp0,2 – od 993 do 925 MPa, Rm – od 1061 do 978 MPa, oraz KV-40 – od 60 do 69 J.

EN

The paper presents the results of a study on the influence of thermomechanical treatment by forging on the microstructure and mechanical properties of a newly developed microalloyed steel containing 0.31% C, 1.41% Mn, 0.033% Ti, 0.008% V and 0.003% B. The applied thermomechanical treatment allows to obtain a fine- -grained microstructure of austenite during hot-working and to manufacture forged parts with an advantageous set of mechanical properties and guaranteed crack resistance after controlled cooling from the finish plastic deformation temperature and successive tempering. Forgings produced with the method of thermomechanical treatment, consecutively subjected to tempering in the temperature range 550-650°C, demonstrate the following values: YS0.2 – 993-925 MPa, UTS – 1061-978 MPa and KV-40 – 60-69 J.

2

Struktura i własności mechaniczne odkuwek ze stali mikrostopowej wytworzonych metodą obróbki cieplno-plastycznej

Opiela M.

Hutnik, Wiadomości Hutnicze

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2013

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Vol. 80, nr 8

579--583

PL

W pracy przedstawiono wyniki badań wpływu obróbki cieplno-plastycznej przez kucie na strukturę i własności mechaniczne stali mikrostopowej zawierającej 0,28% C, 1,41% Mn, 0,027% Nb, 0,028% Ti, 0,019% V i 0,003% B. Zastosowana obróbka cieplno-plastyczna pozwala na uzyskanie drobnoziarnistej struktury austenitu podczas odkształcenia plastycznego stali na gorąco oraz wytwarzanie wyrobów kutych uzyskujących po kontrolowanym chłodzeniu z temperatury końca obróbki plastycznej i następnym wysokim odpuszczaniu korzystny zespół własności mechanicznych i gwarantowaną odporność na pękanie. Odkuwki wytworzone metodą obróbki cieplno-plastycznej poddane następnie odpuszczaniu w zakresie temperatury od 550 do 650 °C wykazują: Rp0,2 od 994 do 939 MPa, Rm od 1084 do 993 MPa oraz KV-40 od 77 do 83 J.

EN

The work presents research results of the influence of thermo-mechanical treatment via forging on microstructure and mechanical properties of newly elaborated microalloyed steel containing of 0.28% C, 1.41% Mn, 0.028% Ti, 0.019% V and 0.003% B. Applied thermo-mechanical treatment allows obtaining fine-grained microstructure of austenite during hot-working and production of forged parts, which acquire advantageous set of mechanical properties and guaranteed crack resistance after controlled cooling from finishing plastic deformation temperature and successive tempering. Forgings produced with the method of thermo-mechanical treatment, consecutively subjected to tempering in the temperature range from 550 to 650 °C, reveal the values of YS0.2 equal from 994 to 939 MPa, UTS from 1084 to 993 MPa and KV -40 from 77 to 83 J.

3

The influence of hot-working conditions on the structure and mechanical properties of forged products of microalloyed steel

Opiela M., Grajcar A., Gołombek K.

Archives of Materials Science and Engineering

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2013

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Vol. 59, nr 1

28--39

EN

Purpose: Results of the effect of thermomechanical processing conditions on the microstructure, mechanical properties and crack resistance are included in the present work. Conditions of forging with the method of thermo-mechanical treatment were developed basing on the analysis of precipitation kinetics of MX interstitial phases in a solid solution, plastometric examinations and investigations of the kinetics of undercooled austenite phase transformations. Design/methodology/approach: Light microscopy and transmission electron microscopy techniques were used to reveal the microstructure of samples obtained as a result of the thermomechanical forging. Mechanical properties and hardness tests as well as resistance to cracking using Charpy V samples at room and lowered temperature were carried out. Findings: Applied thermo-mechanical treatment allows obtaining fine-grained microstructure of austenite during hot-working and production of forged parts, which acquire advantageous set of mechanical properties and guaranteed crack resistance after controlled cooling from finishing plastic deformation temperature and successive tempering. Forgings produced with the method of thermo-mechanical treatment, consecutively subjected to tempering in the temperature range from 550 to 650°C, reveal the values of YS0.2

4

Elaboration of forging conditions on the basis of the precipitation analysis of MX-type phases in microalloyed steels

Opiela M., Grajcar A.

Archives of Civil and Mechanical Engineering

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2012

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Vol. 12, no. 4

427--435

EN

The paper presents analysis of the precipitation of MX-type (M—microalloying element, X—interstitial element) phases in austenite of constructional steels microalloyed with Nb, Ti, V and B, assigned for production of forged elements with the use of thermo-mechanical treatment. The calculations were conducted basing on the dependence of solubility product of MX-type phases in austenite as a function of temperature. The analysis was done on the basis of a simplified thermodynamic model for equilibrium conditions, assuming that individual MX-type phases are soluble in austenite. The solubility of TiN, TiC and NbC as a function of temperature as well as the simplified temperature sequence of precipitation of these phases have been determined. The effect of austenitizing temperature in a range from 900 to 1200 °C on grain size of prior austenite was investigated to verify the analysis. A grain growth corresponds well with a course of a precipitation process, though the limitation of the current model arising from a lack of consideration of complex carbonitrides and the kinetics of a precipitation process should be taken into account. The studies provide the basis for proper design of manufacturing process of thermo-mechanical treatment for high strength forged elements of microalloyed steels.

5

Opracowanie warunków kucia na podstawie analizy kinetyki wydzielania się w austenicie faz międzywęzłowych typu MX

Opiela M.

Hutnik, Wiadomości Hutnicze

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2011

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Vol. 78, nr 8

646--649

PL

W pracy przeprowadzono analizę kinetyki wydzielania się w austenicie faz międzywęzłowych typu MX w nowo opracowanej stali mikrostopowej przeznaczonej do wytwarzania kutych elementów maszyn metodą obróbki cieplno-plastycznej. Weryfikację przeprowadzonej analizy stanowiły badania wpływu temperatury austenityzowania w zakresie od 900 do 1200 oC na wielkość ziaren austenitu pierwotnego. Na podstawie przeprowadzonej analizy opracowano temperaturowe warunki kucia badanej stali.

EN

In this work, the analysis of releasing kinetics of MX-type interstitial phases in the austenite in newly worked out microalloy steel, was made. The investigated steel is assigned for production of forged parts of machines by thermo-mechanical treatment. As a verification of the analysis, the effect of austenitizing temperature, at the range of 900÷1200 °C, on the grain size of primary austenite was investigated. The temperature conditions of forging process of investigated steel were determined on the basis of the carried out analysis.

6

Engineering of forged products of microalloyed constructional steels

Adamczyk J., Opiela M.

Journal of Achievements in Materials and Manufacturing Engineering

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2006

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Vol. 15, nr 1-2

153--158

EN

Purpose: Effect of the thermo-mechanical treatment conditions on the structure and mechanical properties of the forged elements of constructional C-Mn steels with Ti, V, B and N microadditions. Design/methodology/approach: Metallography, electron microscopy, tensile test, hardness measurements, hardenability calculations, Charpy-V tests have been used. Findings: The thermo-mechanical treatment allows to obtain the fine-grained austenite structure during hot plastic deformation, and gives forged elements obtaining: yield point Rp0,2 over 690 MPa, UTS over 770 MPa, hardness 220 up to 250 HB and breaking energy KV over 180J after high tempering. Research limitations/implications: It is predicted TEM investigations on structure of the forged elements after thermo-mechanical treatment. Practical implications: Investigations carried out showed full usability of micro-alloyed steels for producing forged machine parts with the high strength and cracking resistance, using the energy-saving thermo-mechanical treatment method. Originality/value: Production conditions of energy-saving thermo-mechanical treatment of forged elements of HSLA constructional steels – with the diversified hardenability, were presented.