Combining a novel cyclic pre-quenching and two-stage heat treatment in a low-alloyed TRIP-aided steel to significantly enhance mechanical properties through microstructural refinement

Abstract The austenite content of the multiphase TRIP-structure steels depends, inter alia, on the carbon concentration and the properly selected parameters of the two-stage heat treatment. Under the existing industrial conditions, it is possible to (approximately) reproduce approximately the optimal parameters of the two-stage wire rod heat treatment via the controlled wire rod cooling from the end temperature of rolling on the Stelmor line. The investigation of the retained austenite content of TRIP wire rods with a varying carbon concentration, produced under industrial conditions, has been discussed and the effect of the multiphase structure of these wire rods on their mechanical properties has been determined in the paper.

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STUDY ON MECHANICAL PROPERTIES AND MICROSTRUCTURE OF 42CrMo4/NANOS-BA® HIGH-STRENGTH CLAD PLATES AFTER THE PROCESS OF HOT ROLLING AND TWO-STAGE HEAT TREATMENT WITH ISOTHERMAL TRANSFORMATION

Journal of Metallic Materials ◽

10.32730/imz.2657-747.21.1.4 ◽

2021 ◽

Vol 73 (1) ◽

pp. 22-31

Author(s):

Bartłomiej WALNIK ◽

Dariusz Woźniak ◽

Aleksandra NIESZPOREK ◽

Mariusz ADAMCZYK

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Hot Rolling ◽

High Strength ◽

Isothermal Transformation ◽

Two Stage ◽

Physical Experiments ◽

Microstructure Examination ◽

Steel Grades ◽

Stage Heat Treatment

The aim of the study was to develop a technology for welding non-weldable 42CrMo4 and NANOS-BA® steel grades in the process of hot rolling and two-stage heat treatment. As a result of physical experiments carried out in a line for semi-industrial simulation of the production of metals and their alloys (LPS) and additional heat treatment, a durable combination of 42CrMo4 and NANOS-BA® steels with high mechanical properties was obtained, including: Rp0.2 = 1036 MPa, Rm = 1504 MPa and A = 10.9%, without microscopically visible cracks and other discontinuities in the joined surface. The quality of the 42CrMo4/NANOS-BA® clad plates produced in this way was assessed on the basis of microstructure examination as well as bending, shear and tensile strength tests.

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The Effect of a Two-Stage Heat-Treatment on the Microstructural and Mechanical Properties of a Maraging Steel

Materials ◽

10.3390/ma10121346 ◽

2017 ◽

Vol 10 (12) ◽

pp. 1346 ◽

Cited By ~ 9

Author(s):

Thomas Simm ◽

Lin Sun ◽

Deri Galvin ◽

Paul Hill ◽

Martin Rawson ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Maraging Steel ◽

Two Stage ◽

Stage Heat Treatment

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Optimization of mechanical properties of complex, two-stage heat treatment of Cu–Ni (Mn, Mo) austempered ductile iron

Journal of Thermal Analysis and Calorimetry ◽

10.1007/s10973-018-7004-6 ◽

2018 ◽

Vol 132 (2) ◽

pp. 813-822 ◽

Cited By ~ 4

Author(s):

Andrzej Gazda ◽

Małgorzata Warmuzek ◽

Adam Bitka

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Ductile Iron ◽

Austempered Ductile Iron ◽

Two Stage ◽

Stage Heat Treatment

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Crystallization and dielectric properties of SrO–BaO–Nb2O5–GeO2 tungsten–bronze glass–ceramics

Journal of Materials Research ◽

10.1557/jmr.2001.0282 ◽

2001 ◽

Vol 16 (7) ◽

pp. 2057-2063 ◽

Cited By ~ 10

Author(s):

Jiin-Jyh Shyu ◽

Hsin-Wei Peng

Keyword(s):

Heat Treatment ◽

Dielectric Properties ◽

Tungsten Bronze ◽

Glass Ceramics ◽

Dielectric Behavior ◽

Dendritic Morphology ◽

Dielectric Constants ◽

Two Stage ◽

Tetragonal Tungsten Bronze ◽

Stage Heat Treatment

The crystallization and dielectric properties of SrO–BaO–Nb2O5–GeO2 glass–ceramics were investigated. One- and two-stage heat-treatment methods were used to convert the parent glass to glass–ceramics. Strontium barium niobate (SBN) with a tetragonal tungsten-bronze structure formed as the major crystalline phase. When the crystallizing temperature/time was increased, the secondary crystalline BaGe2O5 phase coexisted with SBN. BaGe2O5 formed as a surface layer grown from the surface into the interior of the sample. The dendritic morphology of SBN crystals was examined. The glass–ceramics crystallized by two-stage heat treatment have higher dielectric constants than those crystallized by one-stage heat treatment. The highest dielectric constant that was obtained in the present glass–ceramics was 320. The glass–ceramics showed relaxor-type dielectric behavior.

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Crystallization behavior, Al-Ce intermetallic formation, and microstructure refinement of near-eutectic Al–Si alloys by rare-earth element additions

International Journal of Materials Research (formerly Zeitschrift fuer Metallkunde) ◽

10.1515/ijmr-2020-1111108 ◽

2020 ◽

Vol 111 (11) ◽

pp. 938-952

Author(s):

Bo Chi ◽

Zhiming Shi ◽

Cunquan Wang ◽

Liming Wang ◽

Hao Lian ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Rare Earth ◽

Rare Earth Element ◽

Crystallization Behavior ◽

Earth Element ◽

Microstructural Refinement ◽

Preferential Growth ◽

Intermetallic Formation ◽

The Matrix

Abstract Near-eutectic Al-Si alloys have low strength and high brittleness because of the presence of many eutectic b-Si flakes, needle-like Al-Fe-Si intermetallics, and coarse α-Al grains. This study disclosed the effects of cerium-rich RE (rare earth) element modification on orientation characters of crystals, formation of Al-Ce compounds, and microstructural refinement to improve the microstructure and mechanical properties of the alloys. The RE addition depressed preferential growth along the close-packed and/or sub-closepacked planes and promoted growth along the non-closepacked planes, in which La and other elements were dissolved into needle-like Al11Ce3 phase. When the temperature decreased, Al11Ce3 was preferentially crystallized from the melts and then devitrified by attaching to the surface of β-Al5FeSi needles. Moreover, many small Al11Ce3 particles were precipitated in the matrix and on the Si surface by a T6 heat treatment. Eutectic β-Si phases were constructed into discontinuous networks, short rods, and even particles by RE additions, which were further transformed into fine nodules following the T6 treatment. α-Al grains and primary β-Al5FeSi needles were simultaneously refined. The addition of 1.0 wt.% REs and subsequent T6 treatment yielded the highest tensile strength, elongation, and hardness of the alloy.

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