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Title: The Results Of The Investigation Of Thermomechanical Processing Of PM Steel

Abstract

Hot die forging of PM steel is used to obtain products with high densities. The combination of this process with heat treatment of forgings directly after their forming is researched in order to reduce energy consumption in the manufacture of PM steel products. This work determined the influence of the cooling ratio directly after hot forging of PM steel samples on their structure and mechanical properties. The properties of the PM preforms were examined after sintering and after sintering, quenching into water and tempering for 1 h at 250, 350 and 550 deg. C, respectively, as well as after forging at given temperatures and cooling in water and air, respectively. Forged steel after quenching was tempered at the same temperature as the sintered samples. Good mechanical properties were obtained by hot forging at 1100 deg. C. Sintered steel with 0.6 % Cgraphite is characterized by good hardenability and is susceptible to plastic forming at 1100 - 940 deg. C. During its cooling in air a bainitic-martensitic structure is obtained, whereas after cooling in water the structure is martensitic. The properties of the forged steel are strongly dependent on deformation temperature and cooling conditions. The tensile strength of the forged PMmore » steel with 0.6 Cgraphite after forming at 1100 deg. C is much higher than that of the same heat-treated as-sintered steel. Traditional heat treatment applied to materials after deformation at 1100 deg. C slightly increases properties in comparison to the material directly quenched into water. The best strength was 1585 {+-} 193 MPa, bending strength 3364 {+-} 142 MPa and hardness 588 {+-} 43 HB. Application of controlled cooling of sintered PM steel directly after close-die forging diminishes the energy consumption during product manufacture.« less

Authors:
; ;  [1]
  1. AGH University of Science and Technology, Faculty of Metals Engineering and Industrial Computer Science, al. Mickiewicza 30, 30-059 Cracow (Poland)
Publication Date:
OSTI Identifier:
21057048
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 907; Journal Issue: 1; Conference: 10. ESAFORM conference on material forming, Zaragoza (Spain), 18-20 Apr 2007; Other Information: DOI: 10.1063/1.2729553; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; BENDING; COMPARATIVE EVALUATIONS; COOLING; FLEXURAL STRENGTH; FORGING; HARDNESS; QUENCHING; SINTERING; STEELS; TEMPERING; TENSILE PROPERTIES; THERMOMECHANICAL TREATMENTS; WATER

Citation Formats

Szczepanik, Stefan, Wisniewski, Bartosz, and Krawiarz, Jerzy. The Results Of The Investigation Of Thermomechanical Processing Of PM Steel. United States: N. p., 2007. Web. doi:10.1063/1.2729553.
Szczepanik, Stefan, Wisniewski, Bartosz, & Krawiarz, Jerzy. The Results Of The Investigation Of Thermomechanical Processing Of PM Steel. United States. doi:10.1063/1.2729553.
Szczepanik, Stefan, Wisniewski, Bartosz, and Krawiarz, Jerzy. Sat . "The Results Of The Investigation Of Thermomechanical Processing Of PM Steel". United States. doi:10.1063/1.2729553.
@article{osti_21057048,
title = {The Results Of The Investigation Of Thermomechanical Processing Of PM Steel},
author = {Szczepanik, Stefan and Wisniewski, Bartosz and Krawiarz, Jerzy},
abstractNote = {Hot die forging of PM steel is used to obtain products with high densities. The combination of this process with heat treatment of forgings directly after their forming is researched in order to reduce energy consumption in the manufacture of PM steel products. This work determined the influence of the cooling ratio directly after hot forging of PM steel samples on their structure and mechanical properties. The properties of the PM preforms were examined after sintering and after sintering, quenching into water and tempering for 1 h at 250, 350 and 550 deg. C, respectively, as well as after forging at given temperatures and cooling in water and air, respectively. Forged steel after quenching was tempered at the same temperature as the sintered samples. Good mechanical properties were obtained by hot forging at 1100 deg. C. Sintered steel with 0.6 % Cgraphite is characterized by good hardenability and is susceptible to plastic forming at 1100 - 940 deg. C. During its cooling in air a bainitic-martensitic structure is obtained, whereas after cooling in water the structure is martensitic. The properties of the forged steel are strongly dependent on deformation temperature and cooling conditions. The tensile strength of the forged PM steel with 0.6 Cgraphite after forming at 1100 deg. C is much higher than that of the same heat-treated as-sintered steel. Traditional heat treatment applied to materials after deformation at 1100 deg. C slightly increases properties in comparison to the material directly quenched into water. The best strength was 1585 {+-} 193 MPa, bending strength 3364 {+-} 142 MPa and hardness 588 {+-} 43 HB. Application of controlled cooling of sintered PM steel directly after close-die forging diminishes the energy consumption during product manufacture.},
doi = {10.1063/1.2729553},
journal = {AIP Conference Proceedings},
number = 1,
volume = 907,
place = {United States},
year = {Sat Apr 07 00:00:00 EDT 2007},
month = {Sat Apr 07 00:00:00 EDT 2007}
}
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